The current code currently only stops inserting rehashes into the
chain when no resizes are currently scheduled. As long as resizes
are scheduled and while inserting above the utilization watermark,
more and more rehashes will be scheduled.
This lead to a perfect DoS storm with thousands of rehashes
scheduled which lead to thousands of spinlocks to be taken
sequentially.
Instead, only allow either a series of resizes or a single rehash.
Drop any further rehashes and return -EBUSY.
Fixes: ccd57b1bd3 ("rhashtable: Add immediate rehash during insertion")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
When rhashtable_insert_rehash() fails with ENOMEM, this indicates that
we can't allocate the necessary memory in the current context but the
limits as set by the user would still allow to grow.
Thus attempt an async resize in the background where we can allocate
using GFP_KERNEL which is more likely to succeed. The insertion itself
will still fail to indicate pressure.
This fixes a bug where the table would never continue growing once the
utilization is above 100%.
Fixes: ccd57b1bd3 ("rhashtable: Add immediate rehash during insertion")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The hrtimer code is interested whether the added timer is the first
one to expire and whether the removed timer was the last one in the
tree. The add/del routines have that information already. So we can
return it right away instead of reevaluating it at the call site.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20150414203501.579063647@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull sparc fixes from David Miller:
1) ldc_alloc_exp_dring() can be called from softints, so use
GFP_ATOMIC. From Sowmini Varadhan.
2) Some minor warning/build fixups for the new iommu-common code on
certain archs and with certain debug options enabled. Also from
Sowmini Varadhan.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc: Use GFP_ATOMIC in ldc_alloc_exp_dring() as it can be called in softirq context
sparc64: Use M7 PMC write on all chips T4 and onward.
iommu-common: rename iommu_pool_hash to iommu_hash_common
iommu-common: fix x86_64 compiler warnings
The second and (last) optimized XOR syndrome calculation. This version
supports right and left side optimization. All CPUs with architecture
older than Haswell will benefit from it.
It should be noted that SSE2 movntdq kills performance for memory areas
that are read and written simultaneously in chunks smaller than cache
line size. So use movdqa instead for P/Q writes in sse21 and sse22 XOR
functions.
Signed-off-by: Markus Stockhausen <stockhausen@collogia.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Start the algorithms with the very basic one. It is left and right
optimized. That means we can avoid all calculations for unneeded pages
above the right stop offset. For pages below the left start offset we
still need the syndrome multiplication but without reading data pages.
Signed-off-by: Markus Stockhausen <stockhausen@collogia.de>
Signed-off-by: NeilBrown <neilb@suse.de>
It is always helpful to have a test tool in place if we implement
new data critical algorithms. So add some test routines to the raid6
checker that can prove if the new xor_syndrome() works as expected.
Run through all permutations of start/stop pages per algorithm and
simulate a xor_syndrome() assisted rmw run. After each rmw check if
the recovery algorithm still confirms that the stripe is fine.
Signed-off-by: Markus Stockhausen <stockhausen@collogia.de>
Signed-off-by: NeilBrown <neilb@suse.de>
v3: s-o-b comment, explanation of performance and descision for
the start/stop implementation
Implementing rmw functionality for RAID6 requires optimized syndrome
calculation. Up to now we can only generate a complete syndrome. The
target P/Q pages are always overwritten. With this patch we provide
a framework for inplace P/Q modification. In the first place simply
fill those functions with NULL values.
xor_syndrome() has two additional parameters: start & stop. These
will indicate the first and last page that are changing during a
rmw run. That makes it possible to avoid several unneccessary loops
and speed up calculation. The caller needs to implement the following
logic to make the functions work.
1) xor_syndrome(disks, start, stop, ...): "Remove" all data of source
blocks inside P/Q between (and including) start and end.
2) modify any block with start <= block <= stop
3) xor_syndrome(disks, start, stop, ...): "Reinsert" all data of
source blocks into P/Q between (and including) start and end.
Pages between start and stop that won't be changed should be filled
with a pointer to the kernel zero page. The reasons for not taking NULL
pages are:
1) Algorithms cross the whole source data line by line. Thus avoid
additional branches.
2) Having a NULL page avoids calculating the XOR P parity but still
need calulation steps for the Q parity. Depending on the algorithm
unrolling that might be only a difference of 2 instructions per loop.
The benchmark numbers of the gen_syndrome() functions are displayed in
the kernel log. Do the same for the xor_syndrome() functions. This
will help to analyze performance problems and give an rough estimate
how well the algorithm works. The choice of the fastest algorithm will
still depend on the gen_syndrome() performance.
With the start/stop page implementation the speed can vary a lot in real
life. E.g. a change of page 0 & page 15 on a stripe will be harder to
compute than the case where page 0 & page 1 are XOR candidates. To be not
to enthusiatic about the expected speeds we will run a worse case test
that simulates a change on the upper half of the stripe. So we do:
1) calculation of P/Q for the upper pages
2) continuation of Q for the lower (empty) pages
Signed-off-by: Markus Stockhausen <stockhausen@collogia.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Here's the big char/misc driver patchset for 4.1-rc1.
Lots of different driver subsystem updates here, nothing major, full
details are in the shortlog below.
All of this has been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here's the big char/misc driver patchset for 4.1-rc1.
Lots of different driver subsystem updates here, nothing major, full
details are in the shortlog.
All of this has been in linux-next for a while"
* tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (133 commits)
mei: trace: remove unused TRACE_SYSTEM_STRING
DTS: ARM: OMAP3-N900: Add lis3lv02d support
Documentation: DT: lis302: update wakeup binding
lis3lv02d: DT: add wakeup unit 2 and wakeup threshold
lis3lv02d: DT: use s32 to support negative values
Drivers: hv: hv_balloon: correctly handle num_pages>INT_MAX case
Drivers: hv: hv_balloon: correctly handle val.freeram<num_pages case
mei: replace check for connection instead of transitioning
mei: use mei_cl_is_connected consistently
mei: fix mei_poll operation
hv_vmbus: Add gradually increased delay for retries in vmbus_post_msg()
Drivers: hv: hv_balloon: survive ballooning request with num_pages=0
Drivers: hv: hv_balloon: eliminate jumps in piecewiese linear floor function
Drivers: hv: hv_balloon: do not online pages in offline blocks
hv: remove the per-channel workqueue
hv: don't schedule new works in vmbus_onoffer()/vmbus_onoffer_rescind()
hv: run non-blocking message handlers in the dispatch tasklet
coresight: moving to new "hwtracing" directory
coresight-tmc: Adding a status interface to sysfs
coresight: remove the unnecessary configuration coresight-default-sink
...
When CONFIG_DEBUG_FORCE_WEAK_PER_CPU is set, the DEFINE_PER_CPU_SECTION
macro will define an extern __pcpu_unique_##name variable that could
conflict with the same definition in powerpc at this time. Avoid that
conflict by renaming iommu_pool_hash in iommu-common.c
Thanks to Guenter Roeck for catching this, and helping to test the fix.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
functions, prompted by their mis-use in staging.
With these function removed, all cpu functions should only iterate to
nr_cpu_ids, so we finally only allocate that many bits when cpumasks
are allocated offstack.
Thanks,
Rusty.
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Merge tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull final removal of deprecated cpus_* cpumask functions from Rusty Russell:
"This is the final removal (after several years!) of the obsolete
cpus_* functions, prompted by their mis-use in staging.
With these function removed, all cpu functions should only iterate to
nr_cpu_ids, so we finally only allocate that many bits when cpumasks
are allocated offstack"
* tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (25 commits)
cpumask: remove __first_cpu / __next_cpu
cpumask: resurrect CPU_MASK_CPU0
linux/cpumask.h: add typechecking to cpumask_test_cpu
cpumask: only allocate nr_cpumask_bits.
Fix weird uses of num_online_cpus().
cpumask: remove deprecated functions.
mips: fix obsolete cpumask_of_cpu usage.
x86: fix more deprecated cpu function usage.
ia64: remove deprecated cpus_ usage.
powerpc: fix deprecated CPU_MASK_CPU0 usage.
CPU_MASK_ALL/CPU_MASK_NONE: remove from deprecated region.
staging/lustre/o2iblnd: Don't use cpus_weight
staging/lustre/libcfs: replace deprecated cpus_ calls with cpumask_
staging/lustre/ptlrpc: Do not use deprecated cpus_* functions
blackfin: fix up obsolete cpu function usage.
parisc: fix up obsolete cpu function usage.
tile: fix up obsolete cpu function usage.
arm64: fix up obsolete cpu function usage.
mips: fix up obsolete cpu function usage.
x86: fix up obsolete cpu function usage.
...
The test_data_1_le[] array is a const array of const char *. To avoid
dropping any const information, we need to use "const char * const *",
not just "const char **".
I'm not sure why the different test arrays end up having different
const'ness, but let's make the pointer we use to traverse them as const
as possible, since we modify neither the array of pointers _or_ the
pointers we find in the array.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
They were for use by the deprecated first_cpu() and next_cpu() wrappers,
but sparc used them directly.
They're now replaced by cpumask_first / cpumask_next. And __next_cpu_nr
is completely obsolete.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: David S. Miller <davem@davemloft.net>
Fixes warnings due to
- no DMA_ERROR_CODE on PARISC,
- sizeof (unsigned long) == 4 bytes on PARISC.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Investigation of multithreaded iperf experiments on an ethernet
interface show the iommu->lock as the hottest lock identified by
lockstat, with something of the order of 21M contentions out of
27M acquisitions, and an average wait time of 26 us for the lock.
This is not efficient. A more scalable design is to follow the ppc
model, where the iommu_map_table has multiple pools, each stretching
over a segment of the map, and with a separate lock for each pool.
This model allows for better parallelization of the iommu map search.
This patch adds the iommu range alloc/free function infrastructure.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
I applied the wrong version of this patch series, V4 instead
of V10, due to a patchwork bundling snafu.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull RCU fix from Paul E. McKenney:
"This series contains a single change that fixes Kconfig asking pointless
questions."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull sparc updates from David Miller:
"The PowerPC folks have a really nice scalable IOMMU pool allocator
that we wanted to make use of for sparc. So here we have a series
that abstracts out their code into a common layer that anyone can make
use of.
Sparc is converted, and the PowerPC folks have reviewed and ACK'd this
series and plan to convert PowerPC over as well"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
iommu-common: Fix PARISC compile-time warnings
sparc: Make LDC use common iommu poll management functions
sparc: Make sparc64 use scalable lib/iommu-common.c functions
sparc: Break up monolithic iommu table/lock into finer graularity pools and lock
Fixes warnings due to
- no DMA_ERROR_CODE on PARISC,
- sizeof (unsigned long) == 4 bytes on PARISC.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge third patchbomb from Andrew Morton:
- various misc things
- a couple of lib/ optimisations
- provide DIV_ROUND_CLOSEST_ULL()
- checkpatch updates
- rtc tree
- befs, nilfs2, hfs, hfsplus, fatfs, adfs, affs, bfs
- ptrace fixes
- fork() fixes
- seccomp cleanups
- more mmap_sem hold time reductions from Davidlohr
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (138 commits)
proc: show locks in /proc/pid/fdinfo/X
docs: add missing and new /proc/PID/status file entries, fix typos
drivers/rtc/rtc-at91rm9200.c: make IO endian agnostic
Documentation/spi/spidev_test.c: fix warning
drivers/rtc/rtc-s5m.c: allow usage on device type different than main MFD type
.gitignore: ignore *.tar
MAINTAINERS: add Mediatek SoC mailing list
tomoyo: reduce mmap_sem hold for mm->exe_file
powerpc/oprofile: reduce mmap_sem hold for exe_file
oprofile: reduce mmap_sem hold for mm->exe_file
mips: ip32: add platform data hooks to use DS1685 driver
lib/Kconfig: fix up HAVE_ARCH_BITREVERSE help text
x86: switch to using asm-generic for seccomp.h
sparc: switch to using asm-generic for seccomp.h
powerpc: switch to using asm-generic for seccomp.h
parisc: switch to using asm-generic for seccomp.h
mips: switch to using asm-generic for seccomp.h
microblaze: use asm-generic for seccomp.h
arm: use asm-generic for seccomp.h
seccomp: allow COMPAT sigreturn overrides
...
Cc: Yalin Wang <yalin.wang@sonymobile.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cpumask_next_and() is looking for cpumask_next() in src1 in a loop and
tests if found cpu is also present in src2. remove that loop, perform
cpumask_and() of src1 and src2 first and use that new mask to find
cpumask_next().
Apart from removing while loop, ./bloat-o-meter on x86_64 shows
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8 (-8)
function old new delta
cpumask_next_and 62 54 -8
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Amir Vadai <amirv@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bitmap_empty() has its own implementation. But it's clearly as simple as:
find_first_bit(src, nbits) == nbits
The same is true for 'bitmap_full'.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I hadn't had enough coffee when I wrote this. Currently, the final
increment of buf depends on the value loaded from the table, and
causes gcc to emit a cmov immediately before the return. It is smarter
to let it depend on r, since the increment can then be computed in
parallel with the final load/store pair. It also shaves 16 bytes of
.text.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bucket_find_contain() will search the bucket list for a dma_debug_entry.
When the entry isn't found it needs to search other buckets too, since
only the start address of a dma range is hashed (which might be in a
different bucket).
A copy of the dma_debug_entry is used to get the previous hash bucket
but when its list is searched the original dma_debug_entry is to be used
not its modified copy.
This fixes false "device driver tries to sync DMA memory it has not allocated"
warnings.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The most expensive part of decimal conversion is the divisions by 10
(albeit done using reciprocal multiplication with appropriately chosen
constants). I decided to see if one could eliminate around half of
these multiplications by emitting two digits at a time, at the cost of a
200 byte lookup table, and it does indeed seem like there is something
to be gained, especially on 64 bits. Microbenchmarking shows
improvements ranging from -50% (for numbers uniformly distributed in [0,
2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a
more realistic distribution).
On a larger scale, perf shows that top, one of the big consumers of /proc
data, uses 0.5-1.0% fewer cpu cycles.
I had to jump through some hoops to get the 32 bit code to compile and run
on my 64 bit machine, so I'm not sure how relevant these numbers are, but
just for comparison the microbenchmark showed improvements between -30%
and -10%.
The bloat-o-meter costs are around 150 bytes (the generated code is a
little smaller, so it's not the full 200 bytes) on both 32 and 64 bit.
I'm aware that extra cache misses won't show up in a microbenchmark as
used above, but on the other hand decimal conversions often happen in bulk
(for example in the case of top).
I have of course tested that the new code generates the same output as the
old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9
'random' numbers in-between.
Test and verification code on github: https://github.com/Villemoes/dec.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Tested-by: Jeff Epler <jepler@unpythonic.net>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This file contains implementation for all find_*_bit{,_le}
So giving it more generic name looks reasonable.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently all 'find_*_bit' family is located in lib/find_next_bit.c,
except 'find_last_bit', which is in lib/find_last_bit.c. It seems,
there's no major benefit to have it separated.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patchset does rework to find_bit function family to achieve better
performance, and decrease size of text. All rework is done in patch 1.
Patches 2 and 3 are about code moving and renaming.
It was boot-tested on x86_64 and MIPS (big-endian) machines.
Performance tests were ran on userspace with code like this:
/* addr[] is filled from /dev/urandom */
start = clock();
while (ret < nbits)
ret = find_next_bit(addr, nbits, ret + 1);
end = clock();
printf("%ld\t", (unsigned long) end - start);
On Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz measurements are: (for
find_next_bit, nbits is 8M, for find_first_bit - 80K)
find_next_bit: find_first_bit:
new current new current
26932 43151 14777 14925
26947 43182 14521 15423
26507 43824 15053 14705
27329 43759 14473 14777
26895 43367 14847 15023
26990 43693 15103 15163
26775 43299 15067 15232
27282 42752 14544 15121
27504 43088 14644 14858
26761 43856 14699 15193
26692 43075 14781 14681
27137 42969 14451 15061
... ...
find_next_bit performance gain is 35-40%;
find_first_bit - no measurable difference.
On ARM machine, there is arch-specific implementation for find_bit.
Thanks a lot to George Spelvin and Rasmus Villemoes for hints and
helpful discussions.
This patch (of 3):
New implementations takes less space in source file (see diffstat) and in
object. For me it's 710 vs 453 bytes of text. It also shows better
performance.
find_last_bit description fixed due to obvious typo.
[akpm@linux-foundation.org: include linux/bitmap.h, per Rasmus]
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the usual grab bag of driver updates (lpfc, qla2xxx, storvsc, aacraid,
ipr) plus an assortment of minor updates. There's also a major update to
aic1542 which moves the driver into this millenium.
Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This is the usual grab bag of driver updates (lpfc, qla2xxx, storvsc,
aacraid, ipr) plus an assortment of minor updates. There's also a
major update to aic1542 which moves the driver into this millenium"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (106 commits)
change SCSI Maintainer email
sd, mmc, virtio_blk, string_helpers: fix block size units
ufs: add support to allow non standard behaviours (quirks)
ufs-qcom: save controller revision info in internal structure
qla2xxx: Update driver version to 8.07.00.18-k
qla2xxx: Restore physical port WWPN only, when port down detected for FA-WWPN port.
qla2xxx: Fix virtual port configuration, when switch port is disabled/enabled.
qla2xxx: Prevent multiple firmware dump collection for ISP27XX.
qla2xxx: Disable Interrupt handshake for ISP27XX.
qla2xxx: Add debugging info for MBX timeout.
qla2xxx: Add serdes read/write support for ISP27XX
qla2xxx: Add udev notification to save fw dump for ISP27XX
qla2xxx: Add message for sucessful FW dump collected for ISP27XX.
qla2xxx: Add support to load firmware from file for ISP 26XX/27XX.
qla2xxx: Fix beacon blink for ISP27XX.
qla2xxx: Increase the wait time for firmware to be ready for P3P.
qla2xxx: Fix crash due to wrong casting of reg for ISP27XX.
qla2xxx: Fix warnings reported by static checker.
lpfc: Update version to 10.5.0.0 for upstream patch set
lpfc: Update copyright to 2015
...
Investigation of multithreaded iperf experiments on an ethernet
interface show the iommu->lock as the hottest lock identified by
lockstat, with something of the order of 21M contentions out of
27M acquisitions, and an average wait time of 26 us for the lock.
This is not efficient. A more scalable design is to follow the ppc
model, where the iommu_table has multiple pools, each stretching
over a segment of the map, and with a separate lock for each pool.
This model allows for better parallelization of the iommu map search.
This patch adds the iommu range alloc/free function infrastructure.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge second patchbomb from Andrew Morton:
- the rest of MM
- various misc bits
- add ability to run /sbin/reboot at reboot time
- printk/vsprintf changes
- fiddle with seq_printf() return value
* akpm: (114 commits)
parisc: remove use of seq_printf return value
lru_cache: remove use of seq_printf return value
tracing: remove use of seq_printf return value
cgroup: remove use of seq_printf return value
proc: remove use of seq_printf return value
s390: remove use of seq_printf return value
cris fasttimer: remove use of seq_printf return value
cris: remove use of seq_printf return value
openrisc: remove use of seq_printf return value
ARM: plat-pxa: remove use of seq_printf return value
nios2: cpuinfo: remove use of seq_printf return value
microblaze: mb: remove use of seq_printf return value
ipc: remove use of seq_printf return value
rtc: remove use of seq_printf return value
power: wakeup: remove use of seq_printf return value
x86: mtrr: if: remove use of seq_printf return value
linux/bitmap.h: improve BITMAP_{LAST,FIRST}_WORD_MASK
MAINTAINERS: CREDITS: remove Stefano Brivio from B43
.mailmap: add Ricardo Ribalda
CREDITS: add Ricardo Ribalda Delgado
...
The seq_printf return value, because it's frequently misused,
will eventually be converted to void.
See: commit 1f33c41c03 ("seq_file: Rename seq_overflow() to
seq_has_overflowed() and make public")
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The current semantics of string_escape_mem are inadequate for one of its
current users, vsnprintf(). If that is to honour its contract, it must
know how much space would be needed for the entire escaped buffer, and
string_escape_mem provides no way of obtaining that (short of allocating a
large enough buffer (~4 times input string) to let it play with, and
that's definitely a big no-no inside vsnprintf).
So change the semantics for string_escape_mem to be more snprintf-like:
Return the size of the output that would be generated if the destination
buffer was big enough, but of course still only write to the part of dst
it is allowed to, and (contrary to snprintf) don't do '\0'-termination.
It is then up to the caller to detect whether output was truncated and to
append a '\0' if desired. Also, we must output partial escape sequences,
otherwise a call such as snprintf(buf, 3, "%1pE", "\123") would cause
printf to write a \0 to buf[2] but leaving buf[0] and buf[1] with whatever
they previously contained.
This also fixes a bug in the escaped_string() helper function, which used
to unconditionally pass a length of "end-buf" to string_escape_mem();
since the latter doesn't check osz for being insanely large, it would
happily write to dst. For example, kasprintf(GFP_KERNEL, "something and
then %pE", ...); is an easy way to trigger an oops.
In test-string_helpers.c, the -ENOMEM test is replaced with testing for
getting the expected return value even if the buffer is too small. We
also ensure that nothing is written (by relying on a NULL pointer deref)
if the output size is 0 by passing NULL - this has to work for
kasprintf("%pE") to work.
In net/sunrpc/cache.c, I think qword_add still has the same semantics.
Someone should definitely double-check this.
In fs/proc/array.c, I made the minimum possible change, but longer-term it
should stop poking around in seq_file internals.
[andriy.shevchenko@linux.intel.com: simplify qword_add]
[andriy.shevchenko@linux.intel.com: add missed curly braces]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When printf is given the format specifier %pE, it needs a way of obtaining
the total output size that would be generated if the buffer was large
enough, and string_escape_mem doesn't easily provide that. This is a
refactorization of string_escape_mem in preparation of changing its
external API to provide that information.
The somewhat ugly early returns and subsequent seemingly redundant
conditionals are to make the following patch touch as little as possible
in string_helpers.c while still preserving the current behaviour of never
outputting partial escape sequences. That behaviour must also change for
%pE to work as one expects from every other printf specifier.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The helper hex_string() is broken in two ways. First, it doesn't
increment buf regardless of whether there is room to print, so callers
such as kasprintf() that try to probe the correct storage to allocate will
get a too small return value. But even worse, kasprintf() (and likely
anyone else trying to find the size of the result) pass NULL for buf and 0
for size, so we also have end == NULL. But this means that the end-1 in
hex_string() is (char*)-1, so buf < end-1 is true and we get a NULL
pointer deref. I double-checked this with a trivial kernel module that
just did a kasprintf(GFP_KERNEL, "%14ph", "CrashBoomBang").
Nobody seems to be using %ph with kasprintf, but we might as well fix it
before it hits someone.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add format specifiers for printing struct clk:
- '%pC' or '%pCn': name (Common Clock Framework) or address (legacy
clock framework) of the clock,
- '%pCr': rate of the clock.
[akpm@linux-foundation.org: omit code if !CONFIG_HAVE_CLK]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Making ZEROPAD == '0'-' ', we can eliminate a few more instructions.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc doesn't merge or overlap const char[] objects with identical contents
(probably language lawyers would also insist that these things have
different addresses), but there's no reason to have the string
"0123456789ABCDEF" occur in multiple places. hex_asc_upper is declared in
kernel.h and defined in lib/hexdump.c, which is unconditionally compiled
in.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
At least since the initial git commit, when base was passed as a separate
parameter, number() has only been called with bases 8, 10 and 16. I'm
guessing that 66 was to accommodate 64 0/1, a sign and a '\0', but the
buffer is only used for the actual digits. Octal digits carry 3 bits of
information, so 24 is enough. Spell that 3*sizeof(num) so one less place
needs to be changed should long long ever be 128 bits. Also remove the
commented-out code that would handle an arbitrary base.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since FORMAT_TYPE_INT is simply 1 more than FORMAT_TYPE_UINT, and
similarly for BYTE/UBYTE, SHORT/USHORT, LONG/ULONG, we can eliminate a few
instructions by making SIGN have the value 1 instead of 2, and then use
arithmetic instead of branches for computing the right spec->type. It's a
little hacky, but certainly in the same spirit as SMALL needing to have
the value 0x20. For example for the spec->qualifier == 'l' case, gcc now
generates
75e: 0f b6 53 01 movzbl 0x1(%rbx),%edx
762: 83 e2 01 and $0x1,%edx
765: 83 c2 09 add $0x9,%edx
768: 88 13 mov %dl,(%rbx)
instead of
763: 0f b6 53 01 movzbl 0x1(%rbx),%edx
767: 83 e2 02 and $0x2,%edx
76a: 80 fa 01 cmp $0x1,%dl
76d: 19 d2 sbb %edx,%edx
76f: 83 c2 0a add $0xa,%edx
772: 88 13 mov %dl,(%rbx)
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
const char *...[] is not const, but an array of pointer to const. So
these arrays cannot be __initconst, but must be __initdata
This fixes section conflicts with LTO.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull crypto update from Herbert Xu:
"Here is the crypto update for 4.1:
New interfaces:
- user-space interface for AEAD
- user-space interface for RNG (i.e., pseudo RNG)
New hashes:
- ARMv8 SHA1/256
- ARMv8 AES
- ARMv8 GHASH
- ARM assembler and NEON SHA256
- MIPS OCTEON SHA1/256/512
- MIPS img-hash SHA1/256 and MD5
- Power 8 VMX AES/CBC/CTR/GHASH
- PPC assembler AES, SHA1/256 and MD5
- Broadcom IPROC RNG driver
Cleanups/fixes:
- prevent internal helper algos from being exposed to user-space
- merge common code from assembly/C SHA implementations
- misc fixes"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (169 commits)
crypto: arm - workaround for building with old binutils
crypto: arm/sha256 - avoid sha256 code on ARMv7-M
crypto: x86/sha512_ssse3 - move SHA-384/512 SSSE3 implementation to base layer
crypto: x86/sha256_ssse3 - move SHA-224/256 SSSE3 implementation to base layer
crypto: x86/sha1_ssse3 - move SHA-1 SSSE3 implementation to base layer
crypto: arm64/sha2-ce - move SHA-224/256 ARMv8 implementation to base layer
crypto: arm64/sha1-ce - move SHA-1 ARMv8 implementation to base layer
crypto: arm/sha2-ce - move SHA-224/256 ARMv8 implementation to base layer
crypto: arm/sha256 - move SHA-224/256 ASM/NEON implementation to base layer
crypto: arm/sha1-ce - move SHA-1 ARMv8 implementation to base layer
crypto: arm/sha1_neon - move SHA-1 NEON implementation to base layer
crypto: arm/sha1 - move SHA-1 ARM asm implementation to base layer
crypto: sha512-generic - move to generic glue implementation
crypto: sha256-generic - move to generic glue implementation
crypto: sha1-generic - move to generic glue implementation
crypto: sha512 - implement base layer for SHA-512
crypto: sha256 - implement base layer for SHA-256
crypto: sha1 - implement base layer for SHA-1
crypto: api - remove instance when test failed
crypto: api - Move alg ref count init to crypto_check_alg
...
Pull networking updates from David Miller:
1) Add BQL support to via-rhine, from Tino Reichardt.
2) Integrate SWITCHDEV layer support into the DSA layer, so DSA drivers
can support hw switch offloading. From Floria Fainelli.
3) Allow 'ip address' commands to initiate multicast group join/leave,
from Madhu Challa.
4) Many ipv4 FIB lookup optimizations from Alexander Duyck.
5) Support EBPF in cls_bpf classifier and act_bpf action, from Daniel
Borkmann.
6) Remove the ugly compat support in ARP for ugly layers like ax25,
rose, etc. And use this to clean up the neigh layer, then use it to
implement MPLS support. All from Eric Biederman.
7) Support L3 forwarding offloading in switches, from Scott Feldman.
8) Collapse the LOCAL and MAIN ipv4 FIB tables when possible, to speed
up route lookups even further. From Alexander Duyck.
9) Many improvements and bug fixes to the rhashtable implementation,
from Herbert Xu and Thomas Graf. In particular, in the case where
an rhashtable user bulk adds a large number of items into an empty
table, we expand the table much more sanely.
10) Don't make the tcp_metrics hash table per-namespace, from Eric
Biederman.
11) Extend EBPF to access SKB fields, from Alexei Starovoitov.
12) Split out new connection request sockets so that they can be
established in the main hash table. Much less false sharing since
hash lookups go direct to the request sockets instead of having to
go first to the listener then to the request socks hashed
underneath. From Eric Dumazet.
13) Add async I/O support for crytpo AF_ALG sockets, from Tadeusz Struk.
14) Support stable privacy address generation for RFC7217 in IPV6. From
Hannes Frederic Sowa.
15) Hash network namespace into IP frag IDs, also from Hannes Frederic
Sowa.
16) Convert PTP get/set methods to use 64-bit time, from Richard
Cochran.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1816 commits)
fm10k: Bump driver version to 0.15.2
fm10k: corrected VF multicast update
fm10k: mbx_update_max_size does not drop all oversized messages
fm10k: reset head instead of calling update_max_size
fm10k: renamed mbx_tx_dropped to mbx_tx_oversized
fm10k: update xcast mode before synchronizing multicast addresses
fm10k: start service timer on probe
fm10k: fix function header comment
fm10k: comment next_vf_mbx flow
fm10k: don't handle mailbox events in iov_event path and always process mailbox
fm10k: use separate workqueue for fm10k driver
fm10k: Set PF queues to unlimited bandwidth during virtualization
fm10k: expose tx_timeout_count as an ethtool stat
fm10k: only increment tx_timeout_count in Tx hang path
fm10k: remove extraneous "Reset interface" message
fm10k: separate PF only stats so that VF does not display them
fm10k: use hw->mac.max_queues for stats
fm10k: only show actual queues, not the maximum in hardware
fm10k: allow creation of VLAN on default vid
fm10k: fix unused warnings
...
In a misguided attempt to avoid an #ifdef, the use of the
gp_init_delay module parameter was conditioned on the corresponding
RCU_TORTURE_TEST_SLOW_INIT Kconfig variable, using IS_ENABLED() at
the point of use in the code. This meant that the compiler always saw
the delay, which meant that RCU_TORTURE_TEST_SLOW_INIT_DELAY had to be
unconditionally defined. This in turn caused "make oldconfig" to ask
pointless questions about the value of RCU_TORTURE_TEST_SLOW_INIT_DELAY
in cases where it was not even used.
This commit avoids these pointless questions by defining gp_init_delay
under #ifdef. In one branch, gp_init_delay is initialized to
RCU_TORTURE_TEST_SLOW_INIT_DELAY and is also a module parameter (thus
allowing boot-time modification), and in the other branch gp_init_delay
is a const variable initialized by default to zero.
This approach also simplifies the code at the delay point by eliminating
the IS_DEFINED(). Because gp_init_delay is constant zero in the no-delay
case intended for production use, the "gp_init_delay > 0" check causes
the delay to become dead code, as desired in this case. In addition,
this commit replaces magic constant "10" with the preprocessor variable
PER_RCU_NODE_PERIOD, which controls the number of grace periods that
are allowed to elapse at full speed before a delay is inserted.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Merge first patchbomb from Andrew Morton:
- arch/sh updates
- ocfs2 updates
- kernel/watchdog feature
- about half of mm/
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits)
Documentation: update arch list in the 'memtest' entry
Kconfig: memtest: update number of test patterns up to 17
arm: add support for memtest
arm64: add support for memtest
memtest: use phys_addr_t for physical addresses
mm: move memtest under mm
mm, hugetlb: abort __get_user_pages if current has been oom killed
mm, mempool: do not allow atomic resizing
memcg: print cgroup information when system panics due to panic_on_oom
mm: numa: remove migrate_ratelimited
mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE
mm: split ET_DYN ASLR from mmap ASLR
s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE
mm: expose arch_mmap_rnd when available
s390: standardize mmap_rnd() usage
powerpc: standardize mmap_rnd() usage
mips: extract logic for mmap_rnd()
arm64: standardize mmap_rnd() usage
x86: standardize mmap_rnd() usage
arm: factor out mmap ASLR into mmap_rnd
...
Additional test patterns for memtest were introduced since commit
63823126c2 ("x86: memtest: add additional (regular) test patterns"),
but looks like Kconfig was not updated that time.
Update Kconfig entry with the actual number of maximum test patterns.
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Memtest is a simple feature which fills the memory with a given set of
patterns and validates memory contents, if bad memory regions is detected
it reserves them via memblock API. Since memblock API is widely used by
other architectures this feature can be enabled outside of x86 world.
This patch set promotes memtest to live under generic mm umbrella and
enables memtest feature for arm/arm64.
It was reported that this patch set was useful for tracking down an issue
with some errant DMA on an arm64 platform.
This patch (of 6):
There is nothing platform dependent in the core memtest code, so other
platforms might benefit from this feature too.
[linux@roeck-us.net: MEMTEST depends on MEMBLOCK]
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Implement huge KVA mapping interfaces on x86.
On x86, MTRRs can override PAT memory types with a 4KB granularity. When
using a huge page, MTRRs can override the memory type of the huge page,
which may lead a performance penalty. The processor can also behave in an
undefined manner if a huge page is mapped to a memory range that MTRRs
have mapped with multiple different memory types. Therefore, the mapping
code falls back to use a smaller page size toward 4KB when a mapping range
is covered by non-WB type of MTRRs. The WB type of MTRRs has no affect on
the PAT memory types.
pud_set_huge() and pmd_set_huge() call mtrr_type_lookup() to see if a
given range is covered by MTRRs. MTRR_TYPE_WRBACK indicates that the
range is either covered by WB or not covered and the MTRR default value is
set to WB. 0xFF indicates that MTRRs are disabled.
HAVE_ARCH_HUGE_VMAP is selected when X86_64 or X86_32 with X86_PAE is set.
X86_32 without X86_PAE is not supported since such config can unlikey be
benefited from this feature, and there was an issue found in testing.
[fengguang.wu@intel.com: ioremap_pud_capable can be static]
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ioremap_pud_range() and ioremap_pmd_range() are changed to create huge I/O
mappings when their capability is enabled, and a request meets required
conditions -- both virtual & physical addresses are aligned by their huge
page size, and a requested range fufills their huge page size. When
pud_set_huge() or pmd_set_huge() returns zero, i.e. no-operation is
performed, the code simply falls back to the next level.
The changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined on
the architecture.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when
I/O mappings with pud/pmd are enabled on the kernel.
ioremap_huge_init() calls arch_ioremap_pud_supported() and
arch_ioremap_pmd_supported() to initialize the capabilities at boot-time.
A new kernel option "nohugeiomap" is also added, so that user can disable
the huge I/O map capabilities when necessary.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs update from Al Viro:
"Part one:
- struct filename-related cleanups
- saner iov_iter_init() replacements (and switching the syscalls to
use of those)
- ntfs switch to ->write_iter() (Anton)
- aio cleanups and splitting iocb into common and async parts
(Christoph)
- assorted fixes (me, bfields, Andrew Elble)
There's a lot more, including the completion of switchover to
->{read,write}_iter(), d_inode/d_backing_inode annotations, f_flags
race fixes, etc, but that goes after #for-davem merge. David has
pulled it, and once it's in I'll send the next vfs pull request"
* 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (35 commits)
sg_start_req(): use import_iovec()
sg_start_req(): make sure that there's not too many elements in iovec
blk_rq_map_user(): use import_single_range()
sg_io(): use import_iovec()
process_vm_access: switch to {compat_,}import_iovec()
switch keyctl_instantiate_key_common() to iov_iter
switch {compat_,}do_readv_writev() to {compat_,}import_iovec()
aio_setup_vectored_rw(): switch to {compat_,}import_iovec()
vmsplice_to_user(): switch to import_iovec()
kill aio_setup_single_vector()
aio: simplify arguments of aio_setup_..._rw()
aio: lift iov_iter_init() into aio_setup_..._rw()
lift iov_iter into {compat_,}do_readv_writev()
NFS: fix BUG() crash in notify_change() with patch to chown_common()
dcache: return -ESTALE not -EBUSY on distributed fs race
NTFS: Version 2.1.32 - Update file write from aio_write to write_iter.
VFS: Add iov_iter_fault_in_multipages_readable()
drop bogus check in file_open_root()
switch security_inode_getattr() to struct path *
constify tomoyo_realpath_from_path()
...
Pull RCU changes from Ingo Molnar:
"The main changes in this cycle were:
- changes permitting use of call_rcu() and friends very early in
boot, for example, before rcu_init() is invoked.
- add in-kernel API to enable and disable expediting of normal RCU
grace periods.
- improve RCU's handling of (hotplug-) outgoing CPUs.
- NO_HZ_FULL_SYSIDLE fixes.
- tiny-RCU updates to make it more tiny.
- documentation updates.
- miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
cpu: Provide smpboot_thread_init() on !CONFIG_SMP kernels as well
cpu: Defer smpboot kthread unparking until CPU known to scheduler
rcu: Associate quiescent-state reports with grace period
rcu: Yet another fix for preemption and CPU hotplug
rcu: Add diagnostics to grace-period cleanup
rcutorture: Default to grace-period-initialization delays
rcu: Handle outgoing CPUs on exit from idle loop
cpu: Make CPU-offline idle-loop transition point more precise
rcu: Eliminate ->onoff_mutex from rcu_node structure
rcu: Process offlining and onlining only at grace-period start
rcu: Move rcu_report_unblock_qs_rnp() to common code
rcu: Rework preemptible expedited bitmask handling
rcu: Remove event tracing from rcu_cpu_notify(), used by offline CPUs
rcutorture: Enable slow grace-period initializations
rcu: Provide diagnostic option to slow down grace-period initialization
rcu: Detect stalls caused by failure to propagate up rcu_node tree
rcu: Eliminate empty HOTPLUG_CPU ifdef
rcu: Simplify sync_rcu_preempt_exp_init()
rcu: Put all orphan-callback-related code under same comment
rcu: Consolidate offline-CPU callback initialization
...
Pull trivial tree from Jiri Kosina:
"Usual trivial tree updates. Nothing outstanding -- mostly printk()
and comment fixes and unused identifier removals"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
goldfish: goldfish_tty_probe() is not using 'i' any more
powerpc: Fix comment in smu.h
qla2xxx: Fix printks in ql_log message
lib: correct link to the original source for div64_u64
si2168, tda10071, m88ds3103: Fix firmware wording
usb: storage: Fix printk in isd200_log_config()
qla2xxx: Fix printk in qla25xx_setup_mode
init/main: fix reset_device comment
ipwireless: missing assignment
goldfish: remove unreachable line of code
coredump: Fix do_coredump() comment
stacktrace.h: remove duplicate declaration task_struct
smpboot.h: Remove unused function prototype
treewide: Fix typo in printk messages
treewide: Fix typo in printk messages
mod_devicetable: fix comment for match_flags
Here's the driver-core / kobject / lz4 tree update for 4.1-rc1.
Everything here has been in linux-next for a while with no reported
issues. It's mostly just coding style cleanups, with other minor
changes in here as well, nothing big.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here's the driver-core / kobject / lz4 tree update for 4.1-rc1.
Everything here has been in linux-next for a while with no reported
issues. It's mostly just coding style cleanups, with other minor
changes in here as well, nothing big"
* tag 'driver-core-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (32 commits)
debugfs: allow bad parent pointers to be passed in
stable_kernel_rules: Add clause about specification of kernel versions to patch.
kobject: WARN as tip when call kobject_get() to a kobject not initialized
lib/lz4: Pull out constant tables
drivers: platform: parse IRQ flags from resources
driver core: Make probe deferral more quiet
drivers/core/of: Add symlink to device-tree from devices with an OF node
device: Add dev_of_node() accessor
drivers: base: fw: fix ret value when loading fw
firmware: Avoid manual device_create_file() calls
drivers/base: cacheinfo: validate device node for all the caches
drivers/base: use tabs where possible in code indentation
driver core: add missing blank line after declaration
drivers: base: node: Delete space after pointer declaration
drivers: base: memory: Use tabs instead of spaces
firmware_class: Fix whitespace and indentation
drivers: base: dma-mapping: Erase blank space after pointer
drivers: base: class: Add a blank line after declarations
attribute_container: fix missing blank lines after declarations
drivers: base: memory: Fix switch indent
...
Pull timer updates from Ingo Molnar:
"The main changes in this cycle were:
- clockevents state machine cleanups and enhancements (Viresh Kumar)
- clockevents broadcast notifier horror to state machine conversion
and related cleanups (Thomas Gleixner, Rafael J Wysocki)
- clocksource and timekeeping core updates (John Stultz)
- clocksource driver updates and fixes (Ben Dooks, Dmitry Osipenko,
Hans de Goede, Laurent Pinchart, Maxime Ripard, Xunlei Pang)
- y2038 fixes (Xunlei Pang, John Stultz)
- NMI-safe ktime_get_raw_fast() and general refactoring of the clock
code, in preparation to perf's per event clock ID support (Peter
Zijlstra)
- generic sched/clock fixes, optimizations and cleanups (Daniel
Thompson)
- clockevents cpu_down() race fix (Preeti U Murthy)"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (94 commits)
timers/PM: Drop unnecessary braces from tick_freeze()
timers/PM: Fix up tick_unfreeze()
timekeeping: Get rid of stale comment
clockevents: Cleanup dead cpu explicitely
clockevents: Make tick handover explicit
clockevents: Remove broadcast oneshot control leftovers
sched/idle: Use explicit broadcast oneshot control function
ARM: Tegra: Use explicit broadcast oneshot control function
ARM: OMAP: Use explicit broadcast oneshot control function
intel_idle: Use explicit broadcast oneshot control function
ACPI/idle: Use explicit broadcast control function
ACPI/PAD: Use explicit broadcast oneshot control function
x86/amd/idle, clockevents: Use explicit broadcast oneshot control functions
clockevents: Provide explicit broadcast oneshot control functions
clockevents: Remove the broadcast control leftovers
ARM: OMAP: Use explicit broadcast control function
intel_idle: Use explicit broadcast control function
cpuidle: Use explicit broadcast control function
ACPI/processor: Use explicit broadcast control function
ACPI/PAD: Use explicit broadcast control function
...
Pull core locking changes from Ingo Molnar:
"Main changes:
- jump label asm preparatory work for PowerPC (Anton Blanchard)
- rwsem optimizations and cleanups (Davidlohr Bueso)
- mutex optimizations and cleanups (Jason Low)
- futex fix (Oleg Nesterov)
- remove broken atomicity checks from {READ,WRITE}_ONCE() (Peter
Zijlstra)"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
powerpc, jump_label: Include linux/jump_label.h to get HAVE_JUMP_LABEL define
jump_label: Allow jump labels to be used in assembly
jump_label: Allow asm/jump_label.h to be included in assembly
locking/mutex: Further simplify mutex_spin_on_owner()
locking: Remove atomicy checks from {READ,WRITE}_ONCE
locking/rtmutex: Rename argument in the rt_mutex_adjust_prio_chain() documentation as well
locking/rwsem: Fix lock optimistic spinning when owner is not running
locking: Remove ACCESS_ONCE() usage
locking/rwsem: Check for active lock before bailing on spinning
locking/rwsem: Avoid deceiving lock spinners
locking/rwsem: Set lock ownership ASAP
locking/rwsem: Document barrier need when waking tasks
locking/futex: Check PF_KTHREAD rather than !p->mm to filter out kthreads
locking/mutex: Refactor mutex_spin_on_owner()
locking/mutex: In mutex_spin_on_owner(), return true when owner changes
simillar to iov_iter_fault_in_readable() but differs in that it is
not limited to faulting in the first iovec and instead faults in
"bytes" bytes iterating over the iovecs as necessary.
Also, instead of only faulting in the first and last page of the
range, all pages are faulted in.
This function is needed by NTFS when it does multi page file
writes.
Signed-off-by: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The current string_get_size() overflows when the device size goes over
2^64 bytes because the string helper routine computes the suffix from
the size in bytes. However, the entirety of Linux thinks in terms of
blocks, not bytes, so this will artificially induce an overflow on very
large devices. Fix this by making the function string_get_size() take
blocks and the block size instead of bytes. This should allow us to
keep working until the current SCSI standard overflows.
Also fix virtio_blk and mmc (both of which were also artificially
multiplying by the block size to pass a byte side to string_get_size()).
The mathematics of this is pretty simple: we're taking a product of
size in blocks (S) and block size (B) and trying to re-express this in
exponential form: S*B = R*N^E (where N, the exponent is either 1000 or
1024) and R < N. Mathematically, S = RS*N^ES and B=RB*N^EB, so if RS*RB
< N it's easy to see that S*B = RS*RB*N^(ES+EB). However, if RS*BS > N,
we can see that this can be re-expressed as RS*BS = R*N (where R =
RS*BS/N < N) so the whole exponent becomes R*N^(ES+EB+1)
[jejb: fix incorrect 32 bit do_div spotted by kbuild test robot <fengguang.wu@intel.com>]
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Conflicts:
drivers/net/ethernet/mellanox/mlx4/cmd.c
net/core/fib_rules.c
net/ipv4/fib_frontend.c
The fib_rules.c and fib_frontend.c conflicts were locking adjustments
in 'net' overlapping addition and removal of code in 'net-next'.
The mlx4 conflict was a bug fix in 'net' happening in the same
place a constant was being replaced with a more suitable macro.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull block layer fix from Jens Axboe:
"Just one patch in this pull request, fixing a regression caused by a
'mathematically correct' change to lcm()"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: fix blk_stack_limits() regression due to lcm() change
Now that resizing is completely automatic, we need to remove
the max_size setting or the test will fail.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/usb/asix_common.c
drivers/net/usb/sr9800.c
drivers/net/usb/usbnet.c
include/linux/usb/usbnet.h
net/ipv4/tcp_ipv4.c
net/ipv6/tcp_ipv6.c
The TCP conflicts were overlapping changes. In 'net' we added a
READ_ONCE() to the socket cached RX route read, whilst in 'net-next'
Eric Dumazet touched the surrounding code dealing with how mini
sockets are handled.
With USB, it's a case of the same bug fix first going into net-next
and then I cherry picked it back into net.
Signed-off-by: David S. Miller <davem@davemloft.net>
This is especially important in cases where the kernel allocs a new
structure and expects a field to be set from a netlink attribute. If such
attribute is shorter than expected, the rest of the field is left containing
previous data. When such field is read back by the user space, kernel memory
content is leaked.
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux 3.19 commit 69c953c ("lib/lcm.c: lcm(n,0)=lcm(0,n) is 0, not n")
caused blk_stack_limits() to not properly stack queue_limits for stacked
devices (e.g. DM).
Fix this regression by establishing lcm_not_zero() and switching
blk_stack_limits() over to using it.
DM uses blk_set_stacking_limits() to establish the initial top-level
queue_limits that are then built up based on underlying devices' limits
using blk_stack_limits(). In the case of optimal_io_size (io_opt)
blk_set_stacking_limits() establishes a default value of 0. With commit
69c953c, lcm(0, n) is no longer n, which compromises proper stacking of
the underlying devices' io_opt.
Test:
$ modprobe scsi_debug dev_size_mb=10 num_tgts=1 opt_blks=1536
$ cat /sys/block/sde/queue/optimal_io_size
786432
$ dmsetup create node --table "0 100 linear /dev/sde 0"
Before this fix:
$ cat /sys/block/dm-5/queue/optimal_io_size
0
After this fix:
$ cat /sys/block/dm-5/queue/optimal_io_size
786432
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 3.19+
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
iovec-backed iov_iter instances are assumed to satisfy several properties:
* no more than UIO_MAXIOV elements in iovec array
* total size of all ranges is no more than MAX_RW_COUNT
* all ranges pass access_ok().
The problem is, invariants of data structures should be established in the
primitives creating those data structures, not in the code using those
primitives. And iov_iter_init() violates that principle. For a while we
managed to get away with that, but once the use of iov_iter started to
spread, it didn't take long for shit to hit the fan - missed check in
sys_sendto() had introduced a roothole.
We _do_ have primitives for importing and validating iovecs (both native and
compat ones) and those primitives are almost always followed by shoving the
resulting iovec into iov_iter. Life would be considerably simpler (and safer)
if we combined those primitives with initializing iov_iter.
That gives us two new primitives - import_iovec() and compat_import_iovec().
Calling conventions:
iovec = iov_array;
err = import_iovec(direction, uvec, nr_segs,
ARRAY_SIZE(iov_array), &iovec,
&iter);
imports user vector into kernel space (into iov_array if it fits, allocated
if it doesn't fit or if iovec was NULL), validates it and sets iter up to
refer to it. On success 0 is returned and allocated kernel copy (or NULL
if the array had fit into caller-supplied one) is returned via iovec.
On failure all allocations are undone and -E... is returned. If the total
size of ranges exceeds MAX_RW_COUNT, the excess is silently truncated.
compat_import_iovec() expects uvec to be a pointer to user array of compat_iovec;
otherwise it's identical to import_iovec().
Finally, import_single_range() sets iov_iter backed by single-element iovec
covering a user-supplied range -
err = import_single_range(direction, address, size, iovec, &iter);
does validation and sets iter up. Again, size in excess of MAX_RW_COUNT gets
silently truncated.
Next commits will be switching the things up to use of those and reducing
the amount of iov_iter_init() instances.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull RCU updates from Paul E. McKenney:
- Documentation updates.
- Changes permitting use of call_rcu() and friends very early in
boot, for example, before rcu_init() is invoked.
- Miscellaneous fixes.
- Add in-kernel API to enable and disable expediting of normal RCU
grace periods.
- Improve RCU's handling of (hotplug-) outgoing CPUs.
Note: ARM support is lagging a bit here, and these improved
diagnostics might generate (harmless) splats.
- NO_HZ_FULL_SYSIDLE fixes.
- Tiny RCU updates to make it more tiny.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
nftables sets will be converted to use so called setextensions, moving
the key to a non-fixed position. To hash it, the obj_hashfn must be used,
however it so far doesn't receive the length parameter.
Pass the key length to obj_hashfn() and convert existing users.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There's no reason to allocate the dec{32,64}table on the stack; it
just wastes a bunch of instructions setting them up and, of course,
also consumes quite a bit of stack. Using size_t for such small
integers is a little excessive.
$ scripts/bloat-o-meter /tmp/built-in.o lib/built-in.o
add/remove: 2/2 grow/shrink: 2/0 up/down: 1304/-1548 (-244)
function old new delta
lz4_decompress_unknownoutputsize 55 718 +663
lz4_decompress 55 632 +577
dec64table - 32 +32
dec32table - 32 +32
lz4_uncompress 747 - -747
lz4_uncompress_unknownoutputsize 801 - -801
The now inlined lz4_uncompress functions used to have a stack
footprint of 176 bytes (according to -fstack-usage); their inlinees
have increased their stack use from 32 bytes to 48 and 80 bytes,
respectively.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rhashtable_destroy() variant which stops rehashes, iterates over
the table and calls a callback to release resources.
Avoids need for nft_hash to embed rhashtable internals and allows to
get rid of the being_destroyed flag. It also saves a 2nd mutex
lock upon destruction.
Also fixes an RCU lockdep splash on nft set destruction due to
calling rht_for_each_entry_safe() without holding bucket locks.
Open code this loop as we need know that no mutations may occur in
parallel.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a new bool automatic_shrinking to require the
user to explicitly opt-in to automatic shrinking of tables.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a comment on the choice of the value 16 as the
maximum chain length before we force a rehash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
net/netfilter/nf_tables_core.c
The nf_tables_core.c conflict was resolved using a conflict resolution
from Stephen Rothwell as a guide.
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 963ecbd41a ("rhashtable:
Fix use-after-free in rhashtable_walk_stop") fixed a real bug
but created another one because we may end up sleeping inside an
RCU critical section.
This patch fixes it properly by replacing the mutex with a spin
lock that specifically protects the walker lists.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We need this symbol later on in ipv6.ko, thus export it via EXPORT_SYMBOL
like sha_transform already is.
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch reintroduces immediate rehash during insertion. If
we find during insertion that the table is full or the chain
length exceeds a set limit (currently 16 but may be disabled
with insecure_elasticity) then we will force an immediate rehash.
The rehash will contain an expansion if the table utilisation
exceeds 75%.
If this rehash fails then the insertion will fail. Otherwise the
insertion will be reattempted in the new hash table.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the ability to allocate bucket table with GFP_ATOMIC
instead of GFP_KERNEL. This is needed when we perform an immediate
rehash during insertion.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the missing bits to allow multiple rehashes. The
read-side as well as remove already handle this correctly. So it's
only the rehasher and insertion that need modification to handle
this.
Note that this patch doesn't actually enable it so for now rehashing
is still only performed by the worker thread.
This patch also disables the explicit expand/shrink interface because
the table is meant to expand and shrink automatically, and continuing
to export these interfaces unnecessarily complicates the life of the
rehasher since the rehash process is now composed of two parts.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch changes rhashtable_shrink to shrink to the smallest
size possible rather than halving the table. This is needed
because with multiple rehashing we will defer shrinking until
all other rehashing is done, meaning that when we do shrink
we may be able to shrink a lot.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since every current rhashtable user uses jhash as their hash
function, the fact that jhash is an inline function causes each
user to generate a copy of its code.
This function provides a solution to this problem by allowing
hashfn to be unset. In which case rhashtable will automatically
set it to jhash. Furthermore, if the key length is a multiple
of 4, we will switch over to jhash2.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The walker is a lockless reader so it too needs an smp_rmb before
reading the future_tbl field in order to see any new tables that
may contain elements that we should have walked over.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/emulex/benet/be_main.c
net/core/sysctl_net_core.c
net/ipv4/inet_diag.c
The be_main.c conflict resolution was really tricky. The conflict
hunks generated by GIT were very unhelpful, to say the least. It
split functions in half and moved them around, when the real actual
conflict only existed solely inside of one function, that being
be_map_pci_bars().
So instead, to resolve this, I checked out be_main.c from the top
of net-next, then I applied the be_main.c changes from 'net' since
the last time I merged. And this worked beautifully.
The inet_diag.c and sysctl_net_core.c conflicts were simple
overlapping changes, and were easily to resolve.
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that all rhashtable users have been converted over to the
inline interface, this patch removes the unused out-of-line
interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch converts test_rhashtable to the inlined rhashtable
interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch deals with the complaint that we make indirect function
calls on the fast paths unnecessarily in rhashtable. We resolve
it by moving the fast paths into inline functions that take struct
rhashtable_param (which obviously must be the same set of parameters
supplied to rhashtable_init) as an argument.
The only remaining indirect call is to obj_hashfn (or key_hashfn it
obj_hashfn is unset) on the rehash as well as the insert-during-
rehash slow path.
This patch also extends the support of vairable-length keys to
include those where the key is fixed but scattered in the object.
For example, in netlink we want to key off the namespace and the
portid but they're not next to each other.
This patch does this by directly using the object hash function
as the indicator of whether the key is accessible or not. It
also adds a new function obj_cmpfn to compare a key against an
object. This means that the caller no longer needs to supply
explicit compare functions.
All this is done in a backwards compatible manner so no existing
users are affected until they convert to the new interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch marks the rhashtable_init params argument const as
there is no reason to modify it since we will always make a copy
of it in the rhashtable.
This patch also fixes a bug where we don't actually round up the
value of min_size unless it is less than HASH_MIN_SIZE.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Round up min_size respectively round down max_size to the next power
of two to make sure we always respect the limit specified by the
user. This is required because we compare the table size against the
limit before we expand or shrink.
Also fixes a minor bug where we modified min_size in the params
provided instead of the copy stored in struct rhashtable.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
OPTIMIZER_HIDE_VAR(), as defined when using gcc, is insufficient to
ensure protection from dead store optimization.
For the random driver and crypto drivers, calls are emitted ...
$ gdb vmlinux
(gdb) disassemble memzero_explicit
Dump of assembler code for function memzero_explicit:
0xffffffff813a18b0 <+0>: push %rbp
0xffffffff813a18b1 <+1>: mov %rsi,%rdx
0xffffffff813a18b4 <+4>: xor %esi,%esi
0xffffffff813a18b6 <+6>: mov %rsp,%rbp
0xffffffff813a18b9 <+9>: callq 0xffffffff813a7120 <memset>
0xffffffff813a18be <+14>: pop %rbp
0xffffffff813a18bf <+15>: retq
End of assembler dump.
(gdb) disassemble extract_entropy
[...]
0xffffffff814a5009 <+313>: mov %r12,%rdi
0xffffffff814a500c <+316>: mov $0xa,%esi
0xffffffff814a5011 <+321>: callq 0xffffffff813a18b0 <memzero_explicit>
0xffffffff814a5016 <+326>: mov -0x48(%rbp),%rax
[...]
... but in case in future we might use facilities such as LTO, then
OPTIMIZER_HIDE_VAR() is not sufficient to protect gcc from a possible
eviction of the memset(). We have to use a compiler barrier instead.
Minimal test example when we assume memzero_explicit() would *not* be
a call, but would have been *inlined* instead:
static inline void memzero_explicit(void *s, size_t count)
{
memset(s, 0, count);
<foo>
}
int main(void)
{
char buff[20];
snprintf(buff, sizeof(buff) - 1, "test");
printf("%s", buff);
memzero_explicit(buff, sizeof(buff));
return 0;
}
With <foo> := OPTIMIZER_HIDE_VAR():
(gdb) disassemble main
Dump of assembler code for function main:
[...]
0x0000000000400464 <+36>: callq 0x400410 <printf@plt>
0x0000000000400469 <+41>: xor %eax,%eax
0x000000000040046b <+43>: add $0x28,%rsp
0x000000000040046f <+47>: retq
End of assembler dump.
With <foo> := barrier():
(gdb) disassemble main
Dump of assembler code for function main:
[...]
0x0000000000400464 <+36>: callq 0x400410 <printf@plt>
0x0000000000400469 <+41>: movq $0x0,(%rsp)
0x0000000000400471 <+49>: movq $0x0,0x8(%rsp)
0x000000000040047a <+58>: movl $0x0,0x10(%rsp)
0x0000000000400482 <+66>: xor %eax,%eax
0x0000000000400484 <+68>: add $0x28,%rsp
0x0000000000400488 <+72>: retq
End of assembler dump.
As can be seen, movq, movq, movl are being emitted inlined
via memset().
Reference: http://thread.gmane.org/gmane.linux.kernel.cryptoapi/13764/
Fixes: d4c5efdb97 ("random: add and use memzero_explicit() for clearing data")
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: mancha security <mancha1@zoho.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now that nobody uses max_shift and min_shift, we can safely remove
them.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch converts test_rhashtable to use rhashtable max_size
instead of the obsolete max_shift.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the parameters max_size and min_size which are
meant to replace max_shift and min_shift.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Keeping both size and shift is silly. We only need one.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Caching the lock pointer avoids having to hash on the object
again to unlock the bucket locks.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the part of the compression data are corrupted, or the compression
data is totally fake, the memory access over the limit is possible.
This is the log from my system usning lz4 decompression.
[6502]data abort, halting
[6503]r0 0x00000000 r1 0x00000000 r2 0xdcea0ffc r3 0xdcea0ffc
[6509]r4 0xb9ab0bfd r5 0xdcea0ffc r6 0xdcea0ff8 r7 0xdce80000
[6515]r8 0x00000000 r9 0x00000000 r10 0x00000000 r11 0xb9a98000
[6522]r12 0xdcea1000 usp 0x00000000 ulr 0x00000000 pc 0x820149bc
[6528]spsr 0x400001f3
and the memory addresses of some variables at the moment are
ref:0xdcea0ffc, op:0xdcea0ffc, oend:0xdcea1000
As you can see, COPYLENGH is 8bytes, so @ref and @op can access the momory
over @oend.
Signed-off-by: JeHyeon Yeon <tom.yeon@windriver.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes the following sparse warnings:
lib/rhashtable.c:767:5: warning: context imbalance in 'rhashtable_walk_start' - wrong count at exit
lib/rhashtable.c:849:6: warning: context imbalance in 'rhashtable_walk_stop' - unexpected unlock
Fixes: f2dba9c6ff ("rhashtable: Introduce rhashtable_walk_*")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 9d901bc051 ("rhashtable:
Free bucket tables asynchronously after rehash") causes gratuitous
failures in rhashtable_remove.
The reason is that it inadvertently introduced multiple rehashing
from the perspective of readers. IOW it is now possible to see
more than two tables during a single RCU critical section.
Fortunately the other reader rhashtable_lookup already deals with
this correctly thanks to c4db8848af
("rhashtable: rhashtable: Move future_tbl into struct bucket_table")
so only rhashtable_remove is broken by this change.
This patch fixes this by looping over every table from the first
one to the last or until we find the element that we were trying
to delete.
Incidentally the simple test for detecting rehashing to prevent
starting another shrinking no longer works. Since it isn't needed
anyway (the work queue and the mutex serves as a natural barrier
to unnecessary rehashes) I've simply killed the test.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit c4db8848af ("rhashtable:
Move future_tbl into struct bucket_table") introduced a use-after-
free bug in rhashtable_walk_stop because it dereferences tbl after
droping the RCU read lock.
This patch fixes it by moving the RCU read unlock down to the bottom
of rhashtable_walk_stop. In fact this was how I had it originally
but it got dropped while rearranging patches because this one
depended on the async freeing of bucket_table.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch moves future_tbl to open up the possibility of having
multiple rehashes on the same table.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a rehash counter to bucket_table to indicate
the last bucket that has been rehashed. This serves two purposes:
1. Any bucket that has been rehashed can never gain a new object.
2. If the rehash counter reaches the size of the table, the table
will forever remain empty.
This patch also downsizes bucket_table->size to an unsigned int
since we do not support sizes greater than 32 bits yet.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is in fact no need to wait for an RCU grace period in the
rehash function, since all insertions are guaranteed to go into
the new table through spin locks.
This patch uses call_rcu to free the old/rehashed table at our
leisure.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems that I have already made every rehash redo the random
seed even though my commit message indicated otherwise :)
Since we have already taken that step, this patch goes one step
further and moves the seed initialisation into bucket_table_alloc.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We only nest one level deep there is no need to roll our own
subclasses.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previously whenever the walker encountered a resize it simply
snaps back to the beginning and starts again. However, this only
works if the rehash started and completed while the walker was
idle.
If the walker attempts to restart while the rehash is still ongoing,
we may miss objects that we shouldn't have.
This patch fixes this by making the walker walk the old table
followed by the new table just like all other readers. If a
rehash is detected we will still signal our caller of the fact
so they can prepare for duplicates but we will simply continue
the walk onto the new table after the old one is finished either
by us or by the rehasher.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull gadgetfs fixes from Al Viro:
"Assorted fixes around AIO on gadgetfs: leaks, use-after-free, troubles
caused by ->f_op flipping"
* 'gadget' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
gadgetfs: really get rid of switching ->f_op
gadgetfs: get rid of flipping ->f_op in ep_config()
gadget: switch ep_io_operations to ->read_iter/->write_iter
gadgetfs: use-after-free in ->aio_read()
gadget/function/f_fs.c: switch to ->{read,write}_iter()
gadget/function/f_fs.c: use put iov_iter into io_data
gadget/function/f_fs.c: close leaks
move iov_iter.c from mm/ to lib/
new helper: dup_iter()
Recently there's been requests for better sanity
checking in the time code, so that it's more clear
when something is going wrong, since timekeeping issues
could manifest in a large number of strange ways in
various subsystems.
Thus, this patch adds some extra infrastructure to
add a check to update_wall_time() to print two new
warnings:
1) if we see the call delayed beyond the 'max_cycles'
overflow point,
2) or if we see the call delayed beyond the clocksource's
'max_idle_ns' value, which is currently 50% of the
overflow point.
This extra infrastructure is conditional on
a new CONFIG_DEBUG_TIMEKEEPING option, also
added in this patch - default off.
Tested this a bit by halting qemu for specified
lengths of time to trigger the warnings.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1426133800-29329-5-git-send-email-john.stultz@linaro.org
[ Improved the changelog and the messages a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes a typo rhashtable_lookup_compare where we fail
to recompute the hash when looking up the new table. This causes
elements to be missed and potentially a crash during a resize.
Reported-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit c0c09bfdc4 ("rhashtable: avoid unnecessary wakeup for worker
queue") changed ht->shift to be atomic, which is actually unnecessary.
Instead of leaving the current shift in the core rhashtable structure,
it can be cached inside the individual bucket tables.
There, it will only be initialized once during a new table allocation
in the shrink/expansion slow path, and from then onward it stays immutable
for the rest of the bucket table liftime.
That allows shift to be non-atomic. The patch also moves hash_rnd
management into the table setup. The rhashtable structure now consumes
3 instead of 4 cachelines.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ying Xue <ying.xue@windriver.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a potential race condition between readers and the rehasher.
In particular, the rehasher could have started a rehash while the
reader finishes a scan of the old table but fails to see the new
table pointer.
This patch closes this window by adding smp_wmb/smp_rmb.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Given that CPU-hotplug events are now applied only at the starts of
grace periods, it makes sense to unconditionally enable slow grace-period
initialization for rcutorture testing.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Now that the only caller of obj_raw_hashfn is head_hashfn, we can
simply kill it and fold it into the latter.
This patch also moves the common shift from head_hashfn/key_hashfn
into rht_bucket_index.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
key_hashfn has only one caller and it doesn't really need to supply
the key length as an extra parameter.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that we don't have cross-table hashes, we no longer need to
keep the entire hash value so all users of obj_raw_hashfn can
use head_hashfn instead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch reverts commit c88455ce50
("rhashtable: key_hashfn() must return full hash value") because
the only user of it always masks the hash value.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit aa34a6cb04 ("rhashtable:
Add arbitrary rehash function") killed the annotation on the
nested lock which leads to bitching from lockdep.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a rehash function that supports the use of any
hash function for the new table. This is needed to support changing
the random seed value during the lifetime of the hash table.
However for now the random seed value is still constant and the
rehash function is simply used to replace the existing expand/shrink
functions.
[ ASSERT_BUCKET_LOCK() and thus debug_dump_table() +
debug_dump_buckets() are not longer used, so delete them
entirely. -DaveM ]
Signed-off-by: Herbert Xu <herbert.xu@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently hash_rnd is a parameter that users can set. However,
no existing users set this parameter. It is also something that
people are unlikely to want to set directly since it's just a
random number.
In preparation for allowing the reseeding/rehashing of rhashtable,
this patch moves hash_rnd into bucket_table so that it's now an
internal state rather than a parameter.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Grace-period initialization normally proceeds quite quickly, so
that it is very difficult to reproduce races against grace-period
initialization. This commit therefore allows grace-period
initialization to be artificially slowed down, increasing
race-reproduction probability. A pair of new Kconfig parameters are
provided, CONFIG_RCU_TORTURE_TEST_SLOW_INIT to enable the slowdowns, and
CONFIG_RCU_TORTURE_TEST_SLOW_INIT_DELAY to specify the number of jiffies
of slowdown to apply. A boot-time parameter named rcutree.gp_init_delay
allows boot-time delay to be specified. By default, no delay will be
applied even if CONFIG_RCU_TORTURE_TEST_SLOW_INIT is set.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Now we'll find out the hard way if anyone has CPUMASK_OFFSTACK and is
returning these or assigning them.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Using these functions with offstack cpus is unsafe. They use all NR_CPUS
bits, unstead of nr_cpumask_bits.
In particular, lustre (in staging) used cpus_ and that caused a bug.
Reported-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
contains fixes to ftrace when /proc/sys/kernel/ftrace_enabled and
function tracing are started. Doing the following causes some issues:
# echo 0 > /proc/sys/kernel/ftrace_enabled
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
# echo 1 > /proc/sys/kernel/ftrace_enabled
# echo nop > /sys/kernel/debug/tracing/current_tracer
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
As well as with function tracing too. Pratyush Anand first reported
this issue to me and supplied a patch. When I tested this on my x86
test box, it caused thousands of backtraces and warnings to appear in
dmesg, which also caused a denial of service (a warning for every
function that was listed). I applied Pratyush's patch but it did not
fix the issue for me. I looked into it and found a slight problem
with trampoline accounting. I fixed it and sent Pratyush a patch, but
he said that it did not fix the issue for him.
I later learned tha Pratyush was using an ARM64 server, and when I tested
on my ARM board, I was able to reproduce the same issue as Pratyush.
After applying his patch, it fixed the problem. The above test uncovered
two different bugs, one in x86 and one in ARM and ARM64. As this looked
like it would affect PowerPC, I tested it on my PPC64 box. It too broke,
but neither the patch that fixed ARM or x86 fixed this box (the changes
were all in generic code!). The above test, uncovered two more bugs that
affected PowerPC. Again, the changes were only done to generic code.
It's the way the arch code expected things to be done that was different
between the archs. Some where more sensitive than others.
The rest of this series fixes the PPC bugs as well.
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Merge tag 'trace-fixes-v4.0-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull seq-buf/ftrace fixes from Steven Rostedt:
"This includes fixes for seq_buf_bprintf() truncation issue. It also
contains fixes to ftrace when /proc/sys/kernel/ftrace_enabled and
function tracing are started. Doing the following causes some issues:
# echo 0 > /proc/sys/kernel/ftrace_enabled
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
# echo 1 > /proc/sys/kernel/ftrace_enabled
# echo nop > /sys/kernel/debug/tracing/current_tracer
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
As well as with function tracing too. Pratyush Anand first reported
this issue to me and supplied a patch. When I tested this on my x86
test box, it caused thousands of backtraces and warnings to appear in
dmesg, which also caused a denial of service (a warning for every
function that was listed). I applied Pratyush's patch but it did not
fix the issue for me. I looked into it and found a slight problem
with trampoline accounting. I fixed it and sent Pratyush a patch, but
he said that it did not fix the issue for him.
I later learned tha Pratyush was using an ARM64 server, and when I
tested on my ARM board, I was able to reproduce the same issue as
Pratyush. After applying his patch, it fixed the problem. The above
test uncovered two different bugs, one in x86 and one in ARM and
ARM64. As this looked like it would affect PowerPC, I tested it on my
PPC64 box. It too broke, but neither the patch that fixed ARM or x86
fixed this box (the changes were all in generic code!). The above
test, uncovered two more bugs that affected PowerPC. Again, the
changes were only done to generic code. It's the way the arch code
expected things to be done that was different between the archs. Some
where more sensitive than others.
The rest of this series fixes the PPC bugs as well"
* tag 'trace-fixes-v4.0-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Fix ftrace enable ordering of sysctl ftrace_enabled
ftrace: Fix en(dis)able graph caller when en(dis)abling record via sysctl
ftrace: Clear REGS_EN and TRAMP_EN flags on disabling record via sysctl
seq_buf: Fix seq_buf_bprintf() truncation
seq_buf: Fix seq_buf_vprintf() truncation
In seq_buf_bprintf(), bstr_printf() is used to copy the format into the
buffer remaining in the seq_buf structure. The return of bstr_printf()
is the amount of characters written to the buffer excluding the '\0',
unless the line was truncated!
If the line copied does not fit, it is truncated, and a '\0' is added
to the end of the buffer. But in this case, '\0' is included in the length
of the line written. To know if the buffer had overflowed, the return
length will be the same or greater than the length of the buffer passed in.
The check in seq_buf_bprintf() only checked if the length returned from
bstr_printf() would fit in the buffer, as the seq_buf_bprintf() is only
to be an all or nothing command. It either writes all the string into
the seq_buf, or none of it. If the string is truncated, the pointers
inside the seq_buf must be reset to what they were when the function was
called. This is not the case. On overflow, it copies only part of the string.
The fix is to change the overflow check to see if the length returned from
bstr_printf() is less than the length remaining in the seq_buf buffer, and not
if it is less than or equal to as it currently does. Then seq_buf_bprintf()
will know if the write from bstr_printf() was truncated or not.
Link: http://lkml.kernel.org/r/1425500481.2712.27.camel@perches.com
Cc: stable@vger.kernel.org
Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In seq_buf_vprintf(), vsnprintf() is used to copy the format into the
buffer remaining in the seq_buf structure. The return of vsnprintf()
is the amount of characters written to the buffer excluding the '\0',
unless the line was truncated!
If the line copied does not fit, it is truncated, and a '\0' is added
to the end of the buffer. But in this case, '\0' is included in the length
of the line written. To know if the buffer had overflowed, the return
length will be the same as the length of the buffer passed in.
The check in seq_buf_vprintf() only checked if the length returned from
vsnprintf() would fit in the buffer, as the seq_buf_vprintf() is only
to be an all or nothing command. It either writes all the string into
the seq_buf, or none of it. If the string is truncated, the pointers
inside the seq_buf must be reset to what they were when the function was
called. This is not the case. On overflow, it copies only part of the string.
The fix is to change the overflow check to see if the length returned from
vsnprintf() is less than the length remaining in the seq_buf buffer, and not
if it is less than or equal to as it currently does. Then seq_buf_vprintf()
will know if the write from vsnpritnf() was truncated or not.
Cc: stable@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull networking fixes from David Miller:
1) If an IPVS tunnel is created with a mixed-family destination
address, it cannot be removed. Fix from Alexey Andriyanov.
2) Fix module refcount underflow in netfilter's nft_compat, from Pablo
Neira Ayuso.
3) Generic statistics infrastructure can reference variables sitting on
a released function stack, therefore use dynamic allocation always.
Fix from Ignacy Gawędzki.
4) skb_copy_bits() return value test is inverted in ip_check_defrag().
5) Fix network namespace exit in openvswitch, we have to release all of
the per-net vports. From Pravin B Shelar.
6) Fix signedness bug in CAIF's cfpkt_iterate(), from Dan Carpenter.
7) Fix rhashtable grow/shrink behavior, only expand during inserts and
shrink during deletes. From Daniel Borkmann.
8) Netdevice names with semicolons should never be allowed, because
they serve as a separator. From Matthew Thode.
9) Use {,__}set_current_state() where appropriate, from Fabian
Frederick.
10) Revert byte queue limits support in r8169 driver, it's causing
regressions we can't figure out.
11) tcp_should_expand_sndbuf() erroneously uses tp->packets_out to
measure packets in flight, properly use tcp_packets_in_flight()
instead. From Neal Cardwell.
12) Fix accidental removal of support for bluetooth in CSR based Intel
wireless cards. From Marcel Holtmann.
13) We accidently added a behavioral change between native and compat
tasks, wrt testing the MSG_CMSG_COMPAT bit. Just ignore it if the
user happened to set it in a native binary as that was always the
behavior we had. From Catalin Marinas.
14) Check genlmsg_unicast() return valud in hwsim netlink tx frame
handling, from Bob Copeland.
15) Fix stale ->radar_required setting in mac80211 that can prevent
starting new scans, from Eliad Peller.
16) Fix memory leak in nl80211 monitor, from Johannes Berg.
17) Fix race in TX index handling in xen-netback, from David Vrabel.
18) Don't enable interrupts in amx-xgbe driver until all software et al.
state is ready for the interrupt handler to run. From Thomas
Lendacky.
19) Add missing netlink_ns_capable() checks to rtnl_newlink(), from Eric
W Biederman.
20) The amount of header space needed in macvtap was not calculated
properly, fix it otherwise we splat past the beginning of the
packet. From Eric Dumazet.
21) Fix bcmgenet TCP TX perf regression, from Jaedon Shin.
22) Don't raw initialize or mod timers, use setup_timer() and
mod_timer() instead. From Vaishali Thakkar.
23) Fix software maintained statistics in bcmgenet and systemport
drivers, from Florian Fainelli.
24) DMA descriptor updates in sh_eth need proper memory barriers, from
Ben Hutchings.
25) Don't do UDP Fragmentation Offload on RAW sockets, from Michal
Kubecek.
26) Openvswitch's non-masked set actions aren't constructed properly
into netlink messages, fix from Joe Stringer.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits)
openvswitch: Fix serialization of non-masked set actions.
gianfar: Reduce logging noise seen due to phy polling if link is down
ibmveth: Add function to enable live MAC address changes
net: bridge: add compile-time assert for cb struct size
udp: only allow UFO for packets from SOCK_DGRAM sockets
sh_eth: Really fix padding of short frames on TX
Revert "sh_eth: Enable Rx descriptor word 0 shift for r8a7790"
sh_eth: Fix RX recovery on R-Car in case of RX ring underrun
sh_eth: Ensure proper ordering of descriptor active bit write/read
net/mlx4_en: Disbale GRO for incoming loopback/selftest packets
net/mlx4_core: Fix wrong mask and error flow for the update-qp command
net: systemport: fix software maintained statistics
net: bcmgenet: fix software maintained statistics
rxrpc: don't multiply with HZ twice
rxrpc: terminate retrans loop when sending of skb fails
net/hsr: Fix NULL pointer dereference and refcnt bugs when deleting a HSR interface.
net: pasemi: Use setup_timer and mod_timer
net: stmmac: Use setup_timer and mod_timer
net: 8390: axnet_cs: Use setup_timer and mod_timer
net: 8390: pcnet_cs: Use setup_timer and mod_timer
...
If a hash table has 128 slots and 16384 elems, expand to 256 slots
takes more than one second. For larger sets, a soft lockup is detected.
Holding cpu for that long, even in a work queue is a show stopper
for non preemptable kernels.
cond_resched() at strategic points to allow process scheduler
to reschedule us.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, all real users of rhashtable default their grow and shrink
decision functions to rht_grow_above_75() and rht_shrink_below_30(),
so that there's currently no need to have this explicitly selectable.
It can/should be generic and private inside rhashtable until a real
use case pops up. Since we can make this private, we'll save us this
additional indirection layer and can improve insertion/deletion time
as well.
Reference: http://patchwork.ozlabs.org/patch/443040/
Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
While commit c0c09bfdc4 ("rhashtable: avoid unnecessary wakeup for
worker queue") rightfully moved part of the decision making of
whether we should expand or shrink from the expand/shrink functions
themselves into insert/delete functions in order to avoid unnecessary
worker wake-ups, it however introduced a regression by doing so.
Before that change, if no max_shift was specified (= 0) on rhashtable
initialization, rhashtable_expand() would just grow unconditionally
and lets the available memory be the limiting factor. After that
change, if no max_shift was specified, there would be _no_ expansion
step at all.
Given that netlink and tipc have a max_shift specified, it was not
visible there, but Josh Hunt reported that if nft that starts out
with a default element hint of 3 if not otherwise provided, would
slow i.e. inserts down trememdously as it cannot grow larger to
relax table occupancy.
Given that the test case verifies shrinks/expands manually, we also
must remove pointer to the helper functions to explicitly avoid
parallel resizing on insertions/deletions. test_bucket_stats() and
test_rht_lookup() could also be wrapped around rhashtable mutex to
explicitly synchronize a walk from resizing, but I think that defeats
the actual test case which intended to have explicit test steps,
i.e. 1) inserts, 2) expands, 3) shrinks, 4) deletions, with object
verification after each stage.
Reported-by: Josh Hunt <johunt@akamai.com>
Fixes: c0c09bfdc4 ("rhashtable: avoid unnecessary wakeup for worker queue")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Josh Hunt <johunt@akamai.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the past, it has been useful to enable PROVE_LOCKING without also
enabling PROVE_RCU. However, experience with PROVE_RCU over the past
few years has demonstrated its usefulness, so this commit makes
PROVE_LOCKING directly imply PROVE_RCU.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
With the new standardized functions, we can replace all
ACCESS_ONCE() calls across relevant locking - this includes
lockref and seqlock while at it.
ACCESS_ONCE() does not work reliably on non-scalar types.
For example gcc 4.6 and 4.7 might remove the volatile tag
for such accesses during the SRA (scalar replacement of
aggregates) step:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145
Update the new calls regardless of if it is a scalar type,
this is cleaner than having three alternatives.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1424662301.6539.18.camel@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit f2dba9c6ff ("rhashtable: Introduce rhashtable_walk_*") forgot to
initialize the members of struct rhashtable_walker after allocating it, which
caused an undefined value for 'resize' which is used later on.
Fixes: f2dba9c6ff ("rhashtable: Introduce rhashtable_walk_*")
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's no good reason why to disallow unloading of the rhashtable
test case module.
Commit 9d6dbe1bba moved the code from a boot test into a stand-alone
module, but only converted the subsys_initcall() handler into a
module_init() function without a related exit handler, and thus
preventing the test module from unloading.
Fixes: 9d6dbe1bba ("rhashtable: Make selftest modular")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
When trying to allocate future tables via bucket_table_alloc(), it seems
overkill on large table shifts that we probe for kzalloc() unconditionally
first, as it's likely to fail.
Only probe with kzalloc() for more reasonable table sizes and use vzalloc()
either as a fallback on failure or directly in case of large table sizes.
Fixes: 7e1e77636e ("lib: Resizable, Scalable, Concurrent Hash Table")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Restore pre 54c5b7d311 behaviour and only probe for expansions on inserts
and shrinks on deletes. Currently, it will happen that on initial inserts
into a sparse hash table, we may i.e. shrink it first simply because it's
not fully populated yet, only to later realize that we need to grow again.
This however is counter intuitive, e.g. an initial default size of 64
elements is already small enough, and in case an elements size hint is given
to the hash table by a user, we should avoid unnecessary expansion steps,
so a shrink is clearly unintended here.
Fixes: 54c5b7d311 ("rhashtable: introduce rhashtable_wakeup_worker helper function")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ying Xue <ying.xue@windriver.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
With object runtime debugging enabled, the rhashtable test suite
will rightfully throw a warning "ODEBUG: object is on stack, but
not annotated" from rhashtable_init().
This is because run_work is (correctly) being initialized via
INIT_WORK(), and not annotated by INIT_WORK_ONSTACK(). Meaning,
rhashtable_init() is okay as is, we just need to move ht e.g.,
into global scope.
It never triggered anything, since test_rhashtable is rather a
controlled environment and effectively runs to completion, so
that stack memory is not vanishing underneath us, we shouldn't
confuse any testers with it though.
Fixes: 7e1e77636e ("lib: Resizable, Scalable, Concurrent Hash Table")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull kconfig updates from Michal Marek:
"Yann E Morin was supposed to take over kconfig maintainership, but
this hasn't happened. So I'm sending a few kconfig patches that I
collected:
- Fix for missing va_end in kconfig
- merge_config.sh displays used if given too few arguments
- s/boolean/bool/ in Kconfig files for consistency, with the plan to
only support bool in the future"
* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
kconfig: use va_end to match corresponding va_start
merge_config.sh: Display usage if given too few arguments
kconfig: use bool instead of boolean for type definition attributes
On top of tht is the major rework of lguest, to use PCI and virtio 1.0, to
double-check the implementation.
Then comes the inevitable fixes and cleanups from that work.
Thanks,
Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull virtio updates from Rusty Russell:
"OK, this has the big virtio 1.0 implementation, as specified by OASIS.
On top of tht is the major rework of lguest, to use PCI and virtio
1.0, to double-check the implementation.
Then comes the inevitable fixes and cleanups from that work"
* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (80 commits)
virtio: don't set VIRTIO_CONFIG_S_DRIVER_OK twice.
virtio_net: unconditionally define struct virtio_net_hdr_v1.
tools/lguest: don't use legacy definitions for net device in example launcher.
virtio: Don't expose legacy net features when VIRTIO_NET_NO_LEGACY defined.
tools/lguest: use common error macros in the example launcher.
tools/lguest: give virtqueues names for better error messages
tools/lguest: more documentation and checking of virtio 1.0 compliance.
lguest: don't look in console features to find emerg_wr.
tools/lguest: don't start devices until DRIVER_OK status set.
tools/lguest: handle indirect partway through chain.
tools/lguest: insert driver references from the 1.0 spec (4.1 Virtio Over PCI)
tools/lguest: insert device references from the 1.0 spec (4.1 Virtio Over PCI)
tools/lguest: rename virtio_pci_cfg_cap field to match spec.
tools/lguest: fix features_accepted logic in example launcher.
tools/lguest: handle device reset correctly in example launcher.
virtual: Documentation: simplify and generalize paravirt_ops.txt
lguest: remove NOTIFY call and eventfd facility.
lguest: remove NOTIFY facility from demonstration launcher.
lguest: use the PCI console device's emerg_wr for early boot messages.
lguest: always put console in PCI slot #1.
...
Pull misc VFS updates from Al Viro:
"This cycle a lot of stuff sits on topical branches, so I'll be sending
more or less one pull request per branch.
This is the first pile; more to follow in a few. In this one are
several misc commits from early in the cycle (before I went for
separate branches), plus the rework of mntput/dput ordering on umount,
switching to use of fs_pin instead of convoluted games in
namespace_unlock()"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
switch the IO-triggering parts of umount to fs_pin
new fs_pin killing logics
allow attaching fs_pin to a group not associated with some superblock
get rid of the second argument of acct_kill()
take count and rcu_head out of fs_pin
dcache: let the dentry count go down to zero without taking d_lock
pull bumping refcount into ->kill()
kill pin_put()
mode_t whack-a-mole: chelsio
file->f_path.dentry is pinned down for as long as the file is open...
get rid of lustre_dump_dentry()
gut proc_register() a bit
kill d_validate()
ncpfs: get rid of d_validate() nonsense
selinuxfs: don't open-code d_genocide()
This provides the basic infrastructure to load kernel-specific python
helper scripts when debugging the kernel in gdb.
The loading mechanism is based on gdb loading for <objfile>-gdb.py when
opening <objfile>. Therefore, this places a corresponding link to the
main helper script into the output directory that contains vmlinux.
The main scripts will pull in submodules containing Linux specific gdb
commands and functions. To avoid polluting the source directory with
compiled python modules, we link to them from the object directory.
Due to gdb.parse_and_eval and string redirection for gdb.execute, we
depend on gdb >= 7.2.
This feature is enabled via CONFIG_GDB_SCRIPTS.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Michal Marek <mmarek@suse.cz> [kbuild stuff]
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull crypto update from Herbert Xu:
"Here is the crypto update for 3.20:
- Added 192/256-bit key support to aesni GCM.
- Added MIPS OCTEON MD5 support.
- Fixed hwrng starvation and race conditions.
- Added note that memzero_explicit is not a subsitute for memset.
- Added user-space interface for crypto_rng.
- Misc fixes"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (71 commits)
crypto: tcrypt - do not allocate iv on stack for aead speed tests
crypto: testmgr - limit IV copy length in aead tests
crypto: tcrypt - fix buflen reminder calculation
crypto: testmgr - mark rfc4106(gcm(aes)) as fips_allowed
crypto: caam - fix resource clean-up on error path for caam_jr_init
crypto: caam - pair irq map and dispose in the same function
crypto: ccp - terminate ccp_support array with empty element
crypto: caam - remove unused local variable
crypto: caam - remove dead code
crypto: caam - don't emit ICV check failures to dmesg
hwrng: virtio - drop extra empty line
crypto: replace scatterwalk_sg_next with sg_next
crypto: atmel - Free memory in error path
crypto: doc - remove colons in comments
crypto: seqiv - Ensure that IV size is at least 8 bytes
crypto: cts - Weed out non-CBC algorithms
MAINTAINERS: add linux-crypto to hw random
crypto: cts - Remove bogus use of seqiv
crypto: qat - don't need qat_auth_state struct
crypto: algif_rng - fix sparse non static symbol warning
...
This feature let us to detect accesses out of bounds of global variables.
This will work as for globals in kernel image, so for globals in modules.
Currently this won't work for symbols in user-specified sections (e.g.
__init, __read_mostly, ...)
The idea of this is simple. Compiler increases each global variable by
redzone size and add constructors invoking __asan_register_globals()
function. Information about global variable (address, size, size with
redzone ...) passed to __asan_register_globals() so we could poison
variable's redzone.
This patch also forces module_alloc() to return 8*PAGE_SIZE aligned
address making shadow memory handling (
kasan_module_alloc()/kasan_module_free() ) more simple. Such alignment
guarantees that each shadow page backing modules address space correspond
to only one module_alloc() allocation.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a test module doing various nasty things like out of bounds
accesses, use after free. It is useful for testing kernel debugging
features like kernel address sanitizer.
It mostly concentrates on testing of slab allocator, but we might want to
add more different stuff here in future (like stack/global variables out
of bounds accesses and so on).
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With this patch kasan will be able to catch bugs in memory allocated by
slub. Initially all objects in newly allocated slab page, marked as
redzone. Later, when allocation of slub object happens, requested by
caller number of bytes marked as accessible, and the rest of the object
(including slub's metadata) marked as redzone (inaccessible).
We also mark object as accessible if ksize was called for this object.
There is some places in kernel where ksize function is called to inquire
size of really allocated area. Such callers could validly access whole
allocated memory, so it should be marked as accessible.
Code in slub.c and slab_common.c files could validly access to object's
metadata, so instrumentation for this files are disabled.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Signed-off-by: Dmitry Chernenkov <dmitryc@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds arch specific code for kernel address sanitizer.
16TB of virtual addressed used for shadow memory. It's located in range
[ffffec0000000000 - fffffc0000000000] between vmemmap and %esp fixup
stacks.
At early stage we map whole shadow region with zero page. Latter, after
pages mapped to direct mapping address range we unmap zero pages from
corresponding shadow (see kasan_map_shadow()) and allocate and map a real
shadow memory reusing vmemmap_populate() function.
Also replace __pa with __pa_nodebug before shadow initialized. __pa with
CONFIG_DEBUG_VIRTUAL=y make external function call (__phys_addr)
__phys_addr is instrumented, so __asan_load could be called before shadow
area initialized.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kernel Address sanitizer (KASan) is a dynamic memory error detector. It
provides fast and comprehensive solution for finding use-after-free and
out-of-bounds bugs.
KASAN uses compile-time instrumentation for checking every memory access,
therefore GCC > v4.9.2 required. v4.9.2 almost works, but has issues with
putting symbol aliases into the wrong section, which breaks kasan
instrumentation of globals.
This patch only adds infrastructure for kernel address sanitizer. It's
not available for use yet. The idea and some code was borrowed from [1].
Basic idea:
The main idea of KASAN is to use shadow memory to record whether each byte
of memory is safe to access or not, and use compiler's instrumentation to
check the shadow memory on each memory access.
Address sanitizer uses 1/8 of the memory addressable in kernel for shadow
memory and uses direct mapping with a scale and offset to translate a
memory address to its corresponding shadow address.
Here is function to translate address to corresponding shadow address:
unsigned long kasan_mem_to_shadow(unsigned long addr)
{
return (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET;
}
where KASAN_SHADOW_SCALE_SHIFT = 3.
So for every 8 bytes there is one corresponding byte of shadow memory.
The following encoding used for each shadow byte: 0 means that all 8 bytes
of the corresponding memory region are valid for access; k (1 <= k <= 7)
means that the first k bytes are valid for access, and other (8 - k) bytes
are not; Any negative value indicates that the entire 8-bytes are
inaccessible. Different negative values used to distinguish between
different kinds of inaccessible memory (redzones, freed memory) (see
mm/kasan/kasan.h).
To be able to detect accesses to bad memory we need a special compiler.
Such compiler inserts a specific function calls (__asan_load*(addr),
__asan_store*(addr)) before each memory access of size 1, 2, 4, 8 or 16.
These functions check whether memory region is valid to access or not by
checking corresponding shadow memory. If access is not valid an error
printed.
Historical background of the address sanitizer from Dmitry Vyukov:
"We've developed the set of tools, AddressSanitizer (Asan),
ThreadSanitizer and MemorySanitizer, for user space. We actively use
them for testing inside of Google (continuous testing, fuzzing,
running prod services). To date the tools have found more than 10'000
scary bugs in Chromium, Google internal codebase and various
open-source projects (Firefox, OpenSSL, gcc, clang, ffmpeg, MySQL and
lots of others): [2] [3] [4].
The tools are part of both gcc and clang compilers.
We have not yet done massive testing under the Kernel AddressSanitizer
(it's kind of chicken and egg problem, you need it to be upstream to
start applying it extensively). To date it has found about 50 bugs.
Bugs that we've found in upstream kernel are listed in [5].
We've also found ~20 bugs in out internal version of the kernel. Also
people from Samsung and Oracle have found some.
[...]
As others noted, the main feature of AddressSanitizer is its
performance due to inline compiler instrumentation and simple linear
shadow memory. User-space Asan has ~2x slowdown on computational
programs and ~2x memory consumption increase. Taking into account that
kernel usually consumes only small fraction of CPU and memory when
running real user-space programs, I would expect that kernel Asan will
have ~10-30% slowdown and similar memory consumption increase (when we
finish all tuning).
I agree that Asan can well replace kmemcheck. We have plans to start
working on Kernel MemorySanitizer that finds uses of unitialized
memory. Asan+Msan will provide feature-parity with kmemcheck. As
others noted, Asan will unlikely replace debug slab and pagealloc that
can be enabled at runtime. Asan uses compiler instrumentation, so even
if it is disabled, it still incurs visible overheads.
Asan technology is easily portable to other architectures. Compiler
instrumentation is fully portable. Runtime has some arch-dependent
parts like shadow mapping and atomic operation interception. They are
relatively easy to port."
Comparison with other debugging features:
========================================
KMEMCHECK:
- KASan can do almost everything that kmemcheck can. KASan uses
compile-time instrumentation, which makes it significantly faster than
kmemcheck. The only advantage of kmemcheck over KASan is detection of
uninitialized memory reads.
Some brief performance testing showed that kasan could be
x500-x600 times faster than kmemcheck:
$ netperf -l 30
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to localhost (127.0.0.1) port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
no debug: 87380 16384 16384 30.00 41624.72
kasan inline: 87380 16384 16384 30.00 12870.54
kasan outline: 87380 16384 16384 30.00 10586.39
kmemcheck: 87380 16384 16384 30.03 20.23
- Also kmemcheck couldn't work on several CPUs. It always sets
number of CPUs to 1. KASan doesn't have such limitation.
DEBUG_PAGEALLOC:
- KASan is slower than DEBUG_PAGEALLOC, but KASan works on sub-page
granularity level, so it able to find more bugs.
SLUB_DEBUG (poisoning, redzones):
- SLUB_DEBUG has lower overhead than KASan.
- SLUB_DEBUG in most cases are not able to detect bad reads,
KASan able to detect both reads and writes.
- In some cases (e.g. redzone overwritten) SLUB_DEBUG detect
bugs only on allocation/freeing of object. KASan catch
bugs right before it will happen, so we always know exact
place of first bad read/write.
[1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel
[2] https://code.google.com/p/address-sanitizer/wiki/FoundBugs
[3] https://code.google.com/p/thread-sanitizer/wiki/FoundBugs
[4] https://code.google.com/p/memory-sanitizer/wiki/FoundBugs
[5] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel#Trophies
Based on work by Andrey Konovalov.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that all bitmap formatting usages have been converted to
'%*pb[l]', the separate formatting functions are unnecessary. The
following functions are removed.
* bitmap_scn[list]printf()
* cpumask_scnprintf(), cpulist_scnprintf()
* [__]nodemask_scnprintf(), [__]nodelist_scnprintf()
* seq_bitmap[_list](), seq_cpumask[_list](), seq_nodemask[_list]()
* seq_buf_bitmask()
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
printk and friends can now format bitmaps using '%*pb[l]'. cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bitmap and its derivatives such as cpumask and nodemask currently only
provide formatting functions which put the output string into the
provided buffer; however, how long this buffer should be isn't defined
anywhere and given that some of these bitmaps can be too large to be
formatted into an on-stack buffer it users sometimes are unnecessarily
forced to come up with creative solutions and compromises for the
buffer just to printk these bitmaps.
There have been a couple different attempts at making this easier.
1. Way back, PeterZ tried printk '%pb' extension with the precision
for bit width - '%.*pb'. This was intuitive and made sense but
unfortunately triggered a compile warning about using precision
for a pointer.
http://lkml.kernel.org/g/1336577562.2527.58.camel@twins
2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask
and nodemask. This works but PeterZ pointed out that pr_cont's
tendency to produce broken lines when multiple CPUs are printing is
bothering considering the usages.
http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org
So, this patch is another attempt at teaching printk and friends how
to print bitmaps. It's almost identical to what PeterZ tried with
precision but it uses the field width for the number of bits instead
of precision. The format used is '%*pb[l]', with the optional
trailing 'l' specifying list format instead of hex masks.
This is a valid format string and doesn't trigger compiler warnings;
however, it does make it impossible to specify output field width when
printing bitmaps. I think this is an acceptable trade-off given how
much easier it makes printing bitmaps and that we don't have any
in-kernel user which is using the field width specification. If any
future user wants to use field width with a bitmap, it'd have to
format the bitmap into a string buffer and then print that buffer with
width spec, which isn't different from how it should be done now.
This patch implements bitmap[_list]_string() which are called from the
vsprintf pointer() formatting function. The implementation is mostly
identical to bitmap_scn[list]printf() except that the output is
performed in the vsprintf way. These functions handle formatting into
too small buffers and sprintf() family of functions report the correct
overrun output length.
bitmap_scn[list]printf() are now thin wrappers around scnprintf().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
devm_gen_pool_create() calls devres_alloc() and dereferences its result
without checking whether devres_alloc() succeeded. Check for error and
bail out if it happened.
Coverity-id 1016493.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of potentially passing over the string twice in case c is not
found, just keep track of the last occurrence. According to
bloat-o-meter, this also cuts the generated code by a third (54 vs 36
bytes). Oh, and we get rid of those 7-space indented lines.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 8f243af42a ("sections: fix const sections for crc32 table")
removed the compile-time generated crc32 tables from the RO sections,
because it conflicts with the definition of __cacheline_aligned which
puts all such aligned data into .data..cacheline_aligned section
optimized for wasting less space, and can cause alignment issues when
used in combination with const with some gcc versions like 4.7.0 due to
a gcc bug [1].
Given that most gcc versions should have the fix by now, we can just use
____cacheline_aligned, which only aligns the data but doesn't move it
into specific sections as opposed to __cacheline_aligned. In case of
gcc versions having the mentioned bug, the alignment attribute will have
no effect, but the data will still be made RO.
After patch tables are in RO:
$ nm -v lib/crc32.o | grep -1 -E "crc32c?table"
0000000000000000 t arch_local_irq_enable
0000000000000000 r crc32ctable_le
0000000000000000 t crc32_exit
--
0000000000000960 t test_buf
0000000000002000 r crc32table_be
0000000000004000 r crc32table_le
000000001d1056e5 A __crc_crc32_be
[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52181
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Joe Mario <jmario@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The first of these conditionals is completely redundant: If k == lim-1, we
must have off==0, so the second conditional will also trigger and then it
wouldn't matter if upper had some high bits set. But the second
conditional is in fact also redundant, since it only serves to clear out
some high-order "don't care" bits of dst, about which no guarantee is
made.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can shift the bits from lower and upper into place before assembling
dst[k + off]; moving the shift of lower into the branch where we already
know that rem is non-zero allows us to remove a conditional.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc can generate slightly better code for stuff like "nbits %
BITS_PER_LONG" when it knows nbits is not negative. Since negative size
bitmaps or shift amounts don't make sense, change these parameters of
bitmap_shift_right to unsigned.
If off >= lim (which requires shift >= nbits), k is initialized with a
large positive value, but since I've let k continue to be signed, the loop
will never run and dst will be zeroed as expected. Inside the loop, k is
guaranteed to be non-negative, so the fact that it is promoted to unsigned
in the various expressions it appears in is harmless.
Also use "shift" and "nbits" consistently for the parameter names.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If left is 0, we can just let mask be ~0UL, so that anding with it is a
no-op. Conveniently, BITMAP_LAST_WORD_MASK provides precisely what we
need, and we can eliminate left.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the condition k==lim-1 is true, we must have off == 0 (otherwise, k
could never become that big). But in that case we have upper == 0 and
hence dst[k] == (src[k] & mask) >> rem. Since mask consists of a
consecutive range of bits starting from the LSB, anding dst[k] with mask
is a no-op.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can shift the bits from lower and upper into place before assembling
dst[k]; moving the shift of upper into the branch where we already know
that rem is non-zero allows us to remove a conditional.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I've previously changed the nbits parameter of most bitmap_* functions to
unsigned; now it is bitmap_shift_{left,right}'s turn. This alone saves
some .text, but while at it I found that there were a few other things one
could do. The end result of these seven patches is
$ scripts/bloat-o-meter /tmp/bitmap.o.{old,new}
add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-328 (-328)
function old new delta
__bitmap_shift_right 384 226 -158
__bitmap_shift_left 306 136 -170
and less importantly also a smaller stack footprint
$ stack-o-meter.pl master bitmap
file function old new delta
lib/bitmap.o __bitmap_shift_right 24 8 -16
lib/bitmap.o __bitmap_shift_left 24 0 -24
For each pair of 0 <= shift <= nbits <= 256 I've tested the end result
with a few randomly filled src buffers (including garbage beyond nbits),
in each case verifying that the shift {left,right}-most bits of dst are
zero and the remaining nbits-shift bits correspond to src, so I'm fairly
confident I didn't screw up. That hasn't stopped me from being wrong
before, though.
This patch (of 7):
gcc can generate slightly better code for stuff like "nbits %
BITS_PER_LONG" when it knows nbits is not negative. Since negative size
bitmaps or shift amounts don't make sense, change these parameters of
bitmap_shift_right to unsigned.
The expressions involving "lim - 1" are still ok, since if lim is 0 the
loop is never executed.
Also use "shift" and "nbits" consistently for the parameter names.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On little-endian, there's no reason to have an extra, presumably less
efficient, way of copying a bitmap.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the prototype of bitmap_copy_le the same as bitmap_copy's. All other
bitmap_* functions take unsigned long* parameters; there's no reason this
should be special.
The only current user is the static inline uwb_mas_bm_copy_le, which
already does the void* laundering, so the end users can pass their u8 or
__le32 buffers without a cast.
Furthermore, this allows us to simply let bitmap_copy_le be an alias for
bitmap_copy on little-endian; see next patch.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge third set of updates from Andrew Morton:
- the rest of MM
[ This includes getting rid of the numa hinting bits, in favor of
just generic protnone logic. Yay. - Linus ]
- core kernel
- procfs
- some of lib/ (lots of lib/ material this time)
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (104 commits)
lib/lcm.c: replace include
lib/percpu_ida.c: remove redundant includes
lib/strncpy_from_user.c: replace module.h include
lib/stmp_device.c: replace module.h include
lib/sort.c: move include inside #if 0
lib/show_mem.c: remove redundant include
lib/radix-tree.c: change to simpler include
lib/plist.c: remove redundant include
lib/nlattr.c: remove redundant include
lib/kobject_uevent.c: remove redundant include
lib/llist.c: remove redundant include
lib/md5.c: simplify include
lib/list_sort.c: rearrange includes
lib/genalloc.c: remove redundant include
lib/idr.c: remove redundant include
lib/halfmd4.c: simplify includes
lib/dynamic_queue_limits.c: simplify includes
lib/sort.c: use simpler includes
lib/interval_tree.c: simplify includes
hexdump: make it return number of bytes placed in buffer
...
We don't need all the stuff kernel.h pulls in; just compiler.h since
export.h doesn't do necessary #includes. This removes more than 100
dependencies.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These three #includes seem to be completely redundant: Removing them
yields identical objdump -d output for each of {allyes,allno,def}config,
and neither included file end up in the generated dependency file through
some recursive include. In total, about 50 lines are eliminated from
.percpu.o.cmd.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
strncpy_from_user.c only needs EXPORT_SYMBOL, so just include compiler.h
and export.h instead of the whole module.h machinery.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
stmp_device.c only needs EXPORT_SYMBOL, so just include compiler.h and
export.h instead of the whole module.h machinery.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The sort function and its helpers don't do memory allocation, so the
slab.h include is redundant. Move it inside the #if 0 protecting the
self-test, similar to how it is done in lib/list_sort.c. This removes
over 450 lines from the generated dependency file.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
show_mem.c doesn't use anything from nmi.h. Removing it yields identical
objdump -d output for each of {allyes,allno,def}config and eliminates more
than 100 lines in the dependency file.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The comment helpfully explains why hardirq.h is included, but since
commit 2d4b84739f ("hardirq: Split preempt count mask definitions")
in_interrupt() has been provided by preempt_mask.h. Use that instead,
saving around 40 lines in the generated dependency file.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Removing the include of linux/spinlock.h produces byte-identical output
for {allno,def}config, and identical objdump -d output for allyesconfig.
In the former two cases, more than a 100 lines are eliminated from the
generated dependency file.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
nlattr.c doesn't seem to rely on anything from netdevice.h. Removing it
yields identical objdump -d output for each of {allyes,allno,def}config,
and eliminates more than 200 lines from the generated dependency file.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The file doesn't seem to use anything from linux/user_namespace.h, and
removing it yields byte-identical object code and strictly fewer
dependencies in the .cmd file.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This file doesn't seem to use anything provided by linux/interrupt.h or
anything recursively included through that. Removing it produces
byte-identical output, while reducing .llist.o.cmd from 541 to 156 lines.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
md5.c doesn't use anything from kernel.h, except that that pulls in
compiler.h, which is needed for the export.h to work.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Memory allocation only happens in the self test, just as random numbers
are only used there. So move the inclusion of slab.h inside the
CONFIG_TEST_LIST_SORT.
We don't need module.h and all of the stuff it carries with it, so replace
with export.h and compiler.h. Unfortunately, the ARRAY_SIZE macro from
kernel.h requires the user to ensure bug.h is also included (for
BUILD_BUG_ON_ZERO, used by __must_be_array). We used to get that through
some maze of nested includes, but just include it explicitly.
linux/string.h is then only included implicitly through
kernel.h->printk.h->dynamic_debug.h, but only if !CONFIG_DYNAMIC_DEBUG, so
just include it explicitly (for memset).
objdump -d says the generated code is the same, and wc -l says that
lib/.list_sort.o.cmd went from 579 to 165 lines.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Removing this include produces byte-identical output, and thus removes a
false dependency.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
idr.c doesn't seem to use anything from hardirq.h (or anything included
from that). Removing it produces identical objdump -d output, and gives
44 fewer lines in the .idr.o.cmd dependency file.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We only need EXPORT_SYMBOL, so compiler.h and export.h suffice. This
means linux/types.h is no longer implicitly included, so add an include of
uapi/linux/types.h to linux/cryptohash.h for __u32. Other users of
cryptohash.h cannot be affected, since they must already have been
including uapi/linux/types.h in order for gcc not to complain about
unknown types.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The file doesn't use anything from ctype.h. Instead of module.h, just use
export.h for EXPORT_SYMBOL. The latter requires the user to include
compiler.h, so do that explicitly instead of relying on some other header
pulling it in.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sort.c doesn't use facilities from kernel.h, but does use some types
defined in linux/types.h. Include the latter directly instead of relying
on some other header doing it. Similarly, include linux/export.h directly
instead of through module.h. This removes 80 lines from the dependency
file .sort.o.cmd.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The file uses nothing from init.h, and also doesn't need the full module.h
machinery; export.h is sufficient. The latter requires the user to ensure
compiler.h is included, so do that explicitly instead of relying on some
other header pulling it in.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch makes hexdump return the number of bytes placed in the buffer
excluding trailing NUL. In the case of overflow it returns the desired
amount of bytes to produce the entire dump. Thus, it mimics snprintf().
This will be useful for users that would like to repeat with a bigger
buffer.
[akpm@linux-foundation.org: fix printk warning]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of doing calculations in each case of different groupsize let's do
them beforehand. While there, change the switch to an if-else-if
construction.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the current implementation we have a floating ascii column in the tail
of the dump.
For example, for row size equal to 16 the ascii column as in following
table
group size \ length 8 12 16
1 50 50 50
2 22 32 42
4 20 29 38
8 19 - 36
This patch makes it the same independently of amount of bytes dumped.
The change is safe since all current users, which use ASCII part of the
dump, rely on the group size equal to 1. The patch doesn't change
behaviour for such group size (see the table above).
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Test different scenarios of function calls located in lib/hexdump.c.
Currently hex_dump_to_buffer() is only tested and test data is provided
for little endian CPUs.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since chunk->end_addr is (chunk->start_addr + size - 1), the end address
to compare should be (start + size - 1).
Signed-off-by: Toshi Kikuchi <toshik@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that all in-tree users of strnicmp have been converted to
strncasecmp, the wrapper can be removed.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: David Howells <dhowells@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Also, rename bits to nbits. Both changes for consistency with other
bitmap_* functions.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the return value and the ord and nbits parameters of
bitmap_ord_to_pos unsigned.
Also, simplify the implementation and as a side effect make the result
fully defined, returning nbits for ord >= weight, in analogy with what
find_{first,next}_bit does. This is a better sentinel than the former
("unofficial") 0. No current users are affected by this change.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ordinal of a set bit is simply the number of set bits before it;
counting those doesn't need to be done one bit at a time. While at it,
update the parameters to unsigned int.
It is not completely unthinkable that gcc would see pos as compile-time
constant 0 in one of the uses of bitmap_pos_to_ord. Since the static
inline frontend bitmap_weight doesn't handle nbits==0 correctly (it would
behave exactly as if nbits==BITS_PER_LONG), use __bitmap_weight.
Alternatively, the last line could be spelled bitmap_weight(buf, pos+1)-1,
but this is simpler.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the sz and nbits parameters of bitmap_fold to unsigned int for
consistency with other bitmap_* functions, and to save another few bytes
in the generated code.
[akpm@linux-foundation.org: fix kerneldoc]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the nbits parameter of bitmap_onto to unsigned int for consistency
with other bitmap_* functions.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
string_get_size() was documented to return an error, but in fact always
returned 0. Since the output always fits in 9 bytes, just document that
and let callers do what they do now: pass a small stack buffer and ignore
the return value.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The remainder from do_div is always a u32, and after size has been reduced
to be below 1000 (or 1024), it certainly fits in u32. So both remainder
and sf_cap can be made u32s, the format specifiers can be simplified (%lld
wasn't the right thing to use for _unsigned_ long long anyway), and we can
replace a do_div with an ordinary 32/32 bit division.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While commit 3c9f3681d0 ("[SCSI] lib: add generic helper to print
sizes rounded to the correct SI range") says that Z and Y are included
in preparation for 128 bit computers, they just waste .text currently.
If and when we get u128, string_get_size needs updating anyway (and ISO
needs to come up with four more prefixes).
Also there's no need to include and test for the NULL sentinel; once we
reach "E" size is at most 18. [The test is also wrong; it should be
units_str[units][i+1]; if we've reached NULL we're already doomed.]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All callers of skip_atoi have already checked for the first character
being a digit. In this case, gcc generates simpler code for a do
while-loop.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On 64 bit, size may very well be huge even if bit 31 happens to be 0.
Somehow it doesn't feel right that one can pass a 5 GiB buffer but not a
3 GiB one. So cap at INT_MAX as was probably the intention all along.
This is also the made-up value passed by sprintf and vsprintf.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It seems a little simpler to consume the p from a %p specifier in
format_decode, just as it is done for the surrounding %c, %s and %% cases.
While there, delete a redundant and misplaced comment.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- assorted locking changes so that access to /proc/mdstat
and much of /sys/block/mdXX/md/* is protected by a spinlock
rather than a mutex and will never block indefinitely.
- Make an 'if' condition in RAID5 - which has been implicated
in recent bugs - more readable.
- misc minor fixes
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Merge tag 'md/3.20' of git://neil.brown.name/md
Pull md updates from Neil Brown:
- assorted locking changes so that access to /proc/mdstat
and much of /sys/block/mdXX/md/* is protected by a spinlock
rather than a mutex and will never block indefinitely.
- Make an 'if' condition in RAID5 - which has been implicated
in recent bugs - more readable.
- misc minor fixes
* tag 'md/3.20' of git://neil.brown.name/md: (28 commits)
md/raid10: fix conversion from RAID0 to RAID10
md: wakeup thread upon rdev_dec_pending()
md: make reconfig_mutex optional for writes to md sysfs files.
md: move mddev_lock and related to md.h
md: use mddev->lock to protect updates to resync_{min,max}.
md: minor cleanup in safe_delay_store.
md: move GET_BITMAP_FILE ioctl out from mddev_lock.
md: tidy up set_bitmap_file
md: remove unnecessary 'buf' from get_bitmap_file.
md: remove mddev_lock from rdev_attr_show()
md: remove mddev_lock() from md_attr_show()
md/raid5: use ->lock to protect accessing raid5 sysfs attributes.
md: remove need for mddev_lock() in md_seq_show()
md/bitmap: protect clearing of ->bitmap by mddev->lock
md: protect ->pers changes with mddev->lock
md: level_store: group all important changes into one place.
md: rename ->stop to ->free
md: split detach operation out from ->stop.
md/linear: remove rcu protections in favour of suspend/resume
md: make merge_bvec_fn more robust in face of personality changes.
...
Pull ARM updates from Russell King:
- clang assembly fixes from Ard
- optimisations and cleanups for Aurora L2 cache support
- efficient L2 cache support for secure monitor API on Exynos SoCs
- debug menu cleanup from Daniel Thompson to allow better behaviour for
multiplatform kernels
- StrongARM SA11x0 conversion to irq domains, and pxa_timer
- kprobes updates for older ARM CPUs
- move probes support out of arch/arm/kernel to arch/arm/probes
- add inline asm support for the rbit (reverse bits) instruction
- provide an ARM mode secondary CPU entry point (for Qualcomm CPUs)
- remove the unused ARMv3 user access code
- add driver_override support to AMBA Primecell bus
* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (55 commits)
ARM: 8256/1: driver coamba: add device binding path 'driver_override'
ARM: 8301/1: qcom: Use secondary_startup_arm()
ARM: 8302/1: Add a secondary_startup that assumes ARM mode
ARM: 8300/1: teach __asmeq that r11 == fp and r12 == ip
ARM: kprobes: Fix compilation error caused by superfluous '*'
ARM: 8297/1: cache-l2x0: optimize aurora range operations
ARM: 8296/1: cache-l2x0: clean up aurora cache handling
ARM: 8284/1: sa1100: clear RCSR_SMR on resume
ARM: 8283/1: sa1100: collie: clear PWER register on machine init
ARM: 8282/1: sa1100: use handle_domain_irq
ARM: 8281/1: sa1100: move GPIO-related IRQ code to gpio driver
ARM: 8280/1: sa1100: switch to irq_domain_add_simple()
ARM: 8279/1: sa1100: merge both GPIO irqdomains
ARM: 8278/1: sa1100: split irq handling for low GPIOs
ARM: 8291/1: replace magic number with PAGE_SHIFT macro in fixup_pv code
ARM: 8290/1: decompressor: fix a wrong comment
ARM: 8286/1: mm: Fix dma_contiguous_reserve comment
ARM: 8248/1: pm: remove outdated comment
ARM: 8274/1: Fix DEBUG_LL for multi-platform kernels (without PL01X)
ARM: 8273/1: Seperate DEBUG_UART_PHYS from DEBUG_LL on EP93XX
...
Pull security layer updates from James Morris:
"Highlights:
- Smack adds secmark support for Netfilter
- /proc/keys is now mandatory if CONFIG_KEYS=y
- TPM gets its own device class
- Added TPM 2.0 support
- Smack file hook rework (all Smack users should review this!)"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (64 commits)
cipso: don't use IPCB() to locate the CIPSO IP option
SELinux: fix error code in policydb_init()
selinux: add security in-core xattr support for pstore and debugfs
selinux: quiet the filesystem labeling behavior message
selinux: Remove unused function avc_sidcmp()
ima: /proc/keys is now mandatory
Smack: Repair netfilter dependency
X.509: silence asn1 compiler debug output
X.509: shut up about included cert for silent build
KEYS: Make /proc/keys unconditional if CONFIG_KEYS=y
MAINTAINERS: email update
tpm/tpm_tis: Add missing ifdef CONFIG_ACPI for pnp_acpi_device
smack: fix possible use after frees in task_security() callers
smack: Add missing logging in bidirectional UDS connect check
Smack: secmark support for netfilter
Smack: Rework file hooks
tpm: fix format string error in tpm-chip.c
char/tpm/tpm_crb: fix build error
smack: Fix a bidirectional UDS connect check typo
smack: introduce a special case for tmpfs in smack_d_instantiate()
...
Pull s390 updates from Martin Schwidefsky:
- The remaining patches for the z13 machine support: kernel build
option for z13, the cache synonym avoidance, SMT support,
compare-and-delay for spinloops and the CES5S crypto adapater.
- The ftrace support for function tracing with the gcc hotpatch option.
This touches common code Makefiles, Steven is ok with the changes.
- The hypfs file system gets an extension to access diagnose 0x0c data
in user space for performance analysis for Linux running under z/VM.
- The iucv hvc console gets wildcard spport for the user id filtering.
- The cacheinfo code is converted to use the generic infrastructure.
- Cleanup and bug fixes.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits)
s390/process: free vx save area when releasing tasks
s390/hypfs: Eliminate hypfs interval
s390/hypfs: Add diagnose 0c support
s390/cacheinfo: don't use smp_processor_id() in preemptible context
s390/zcrypt: fixed domain scanning problem (again)
s390/smp: increase maximum value of NR_CPUS to 512
s390/jump label: use different nop instruction
s390/jump label: add sanity checks
s390/mm: correct missing space when reporting user process faults
s390/dasd: cleanup profiling
s390/dasd: add locking for global_profile access
s390/ftrace: hotpatch support for function tracing
ftrace: let notrace function attribute disable hotpatching if necessary
ftrace: allow architectures to specify ftrace compile options
s390: reintroduce diag 44 calls for cpu_relax()
s390/zcrypt: Add support for new crypto express (CEX5S) adapter.
s390/zcrypt: Number of supported ap domains is not retrievable.
s390/spinlock: add compare-and-delay to lock wait loops
s390/tape: remove redundant if statement
s390/hvc_iucv: add simple wildcard matches to the iucv allow filter
...
Pull networking updates from David Miller:
1) More iov_iter conversion work from Al Viro.
[ The "crypto: switch af_alg_make_sg() to iov_iter" commit was
wrong, and this pull actually adds an extra commit on top of the
branch I'm pulling to fix that up, so that the pre-merge state is
ok. - Linus ]
2) Various optimizations to the ipv4 forwarding information base trie
lookup implementation. From Alexander Duyck.
3) Remove sock_iocb altogether, from CHristoph Hellwig.
4) Allow congestion control algorithm selection via routing metrics.
From Daniel Borkmann.
5) Make ipv4 uncached route list per-cpu, from Eric Dumazet.
6) Handle rfs hash collisions more gracefully, also from Eric Dumazet.
7) Add xmit_more support to r8169, e1000, and e1000e drivers. From
Florian Westphal.
8) Transparent Ethernet Bridging support for GRO, from Jesse Gross.
9) Add BPF packet actions to packet scheduler, from Jiri Pirko.
10) Add support for uniqu flow IDs to openvswitch, from Joe Stringer.
11) New NetCP ethernet driver, from Muralidharan Karicheri and Wingman
Kwok.
12) More sanely handle out-of-window dupacks, which can result in
serious ACK storms. From Neal Cardwell.
13) Various rhashtable bug fixes and enhancements, from Herbert Xu,
Patrick McHardy, and Thomas Graf.
14) Support xmit_more in be2net, from Sathya Perla.
15) Group Policy extensions for vxlan, from Thomas Graf.
16) Remove Checksum Offload support for vxlan, from Tom Herbert.
17) Like ipv4, support lockless transmit over ipv6 UDP sockets. From
Vlad Yasevich.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1494+1 commits)
crypto: fix af_alg_make_sg() conversion to iov_iter
ipv4: Namespecify TCP PMTU mechanism
i40e: Fix for stats init function call in Rx setup
tcp: don't include Fast Open option in SYN-ACK on pure SYN-data
openvswitch: Only set TUNNEL_VXLAN_OPT if VXLAN-GBP metadata is set
ipv6: Make __ipv6_select_ident static
ipv6: Fix fragment id assignment on LE arches.
bridge: Fix inability to add non-vlan fdb entry
net: Mellanox: Delete unnecessary checks before the function call "vunmap"
cxgb4: Add support in cxgb4 to get expansion rom version via ethtool
ethtool: rename reserved1 memeber in ethtool_drvinfo for expansion ROM version
net: dsa: Remove redundant phy_attach()
IB/mlx4: Reset flow support for IB kernel ULPs
IB/mlx4: Always use the correct port for mirrored multicast attachments
net/bonding: Fix potential bad memory access during bonding events
tipc: remove tipc_snprintf
tipc: nl compat add noop and remove legacy nl framework
tipc: convert legacy nl stats show to nl compat
tipc: convert legacy nl net id get to nl compat
tipc: convert legacy nl net id set to nl compat
...
Pull trivial tree changes from Jiri Kosina:
"Patches from trivial.git that keep the world turning around.
Mostly documentation and comment fixes, and a two corner-case code
fixes from Alan Cox"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
kexec, Kconfig: spell "architecture" properly
mm: fix cleancache debugfs directory path
blackfin: mach-common: ints-priority: remove unused function
doubletalk: probe failure causes OOPS
ARM: cache-l2x0.c: Make it clear that cache-l2x0 handles L310 cache controller
msdos_fs.h: fix 'fields' in comment
scsi: aic7xxx: fix comment
ARM: l2c: fix comment
ibmraid: fix writeable attribute with no store method
dynamic_debug: fix comment
doc: usbmon: fix spelling s/unpriviledged/unprivileged/
x86: init_mem_mapping(): use capital BIOS in comment
Pull RCU updates from Ingo Molnar:
"The main RCU changes in this cycle are:
- Documentation updates.
- Miscellaneous fixes.
- Preemptible-RCU fixes, including fixing an old bug in the
interaction of RCU priority boosting and CPU hotplug.
- SRCU updates.
- RCU CPU stall-warning updates.
- RCU torture-test updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
rcu: Initialize tiny RCU stall-warning timeouts at boot
rcu: Fix RCU CPU stall detection in tiny implementation
rcu: Add GP-kthread-starvation checks to CPU stall warnings
rcu: Make cond_resched_rcu_qs() apply to normal RCU flavors
rcu: Optionally run grace-period kthreads at real-time priority
ksoftirqd: Use new cond_resched_rcu_qs() function
ksoftirqd: Enable IRQs and call cond_resched() before poking RCU
rcutorture: Add more diagnostics in rcu_barrier() test failure case
torture: Flag console.log file to prevent holdovers from earlier runs
torture: Add "-enable-kvm -soundhw pcspk" to qemu command line
rcutorture: Handle different mpstat versions
rcutorture: Check from beginning to end of grace period
rcu: Remove redundant rcu_batches_completed() declaration
rcutorture: Drop rcu_torture_completed() and friends
rcu: Provide rcu_batches_completed_sched() for TINY_RCU
rcutorture: Use unsigned for Reader Batch computations
rcutorture: Make build-output parsing correctly flag RCU's warnings
rcu: Make _batches_completed() functions return unsigned long
rcutorture: Issue warnings on close calls due to Reader Batch blows
documentation: Fix smp typo in memory-barriers.txt
...
The remove logic properly searched the remaining chain for a matching
entry with an identical hash but it did this while searching from both
the old and new table. Instead in order to not leave stale references
behind we need to:
1. When growing and searching from the new table:
Search remaining chain for entry with same hash to avoid having
the new table directly point to a entry with a different hash.
2. When shrinking and searching from the old table:
Check if the element after the removed would create a cross
reference and avoid it if so.
These bugs were present from the beginning in nft_hash.
Also, both insert functions calculated the hash based on the mask of
the new table. This worked while growing. Wwhile shrinking, the mask
of the inew table is smaller than the mask of the old table. This lead
to a bit not being taken into account when selecting the bucket lock
and thus caused the wrong bucket to be locked eventually.
Fixes: 7e1e77636e ("lib: Resizable, Scalable, Concurrent Hash Table")
Fixes: 97defe1ecf ("rhashtable: Per bucket locks & deferred expansion/shrinking")
Reported-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
During a resize, when two buckets in the larger table map to
a single bucket in the smaller table and the new table has already
been (partially) linked to the old table. Removal of an element
may result the bucket in the larger table to point to entries
which all hash to a different value than the bucket index. Thus
causing two buckets to point to the same sub chain after unzipping.
This is not illegal *during* the resize phase but after it has
completed.
Keep the old table around until all of the unzipping is done to
allow the removal code to only search for matching hashed entries
during this special period.
Reported-by: Ying Xue <ying.xue@windriver.com>
Fixes: 97defe1ecf ("rhashtable: Per bucket locks & deferred expansion/shrinking")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Catch hash miscalculations which result in hard to track down race
conditions.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This simplifies debugging of locking violations if compiled with
CONFIG_PROVE_LOCKING.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
We need to wait for all RCU readers to complete after the last bit of
unzipping has been completed. Otherwise the old table is freed up
prematurely.
Fixes: 7e1e77636e ("lib: Resizable, Scalable, Concurrent Hash Table")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
rhashtable currently allows to use a bucket lock per bucket. This
requires multiple levels of complicated nested locking because when
resizing, a single bucket of the smaller table will map to two
buckets in the larger table. So far rhashtable has explicitly locked
both buckets in the larger table.
By excluding the highest bit of the hash from the bucket lock map and
thus only allowing locks to buckets in a ratio of 1:2, the locking
can be simplified a lot without losing the benefits of multiple locks.
Larger tables which benefit from multiple locks will not have a single
lock per bucket anyway.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The value computed by key_hashfn() is used by rhashtable_lookup_compare()
to traverse both tables during a resize. key_hashfn() must therefore
return the hash value without the buckets mask applied so it can be
masked to the size of each individual table.
Fixes: 97defe1ecf ("rhashtable: Per bucket locks & deferred expansion/shrinking")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/vxlan.c
drivers/vhost/net.c
include/linux/if_vlan.h
net/core/dev.c
The net/core/dev.c conflict was the overlap of one commit marking an
existing function static whilst another was adding a new function.
In the include/linux/if_vlan.h case, the type used for a local
variable was changed in 'net', whereas the function got rewritten
to fix a stacked vlan bug in 'net-next'.
In drivers/vhost/net.c, Al Viro's iov_iter conversions in 'net-next'
overlapped with an endainness fix for VHOST 1.0 in 'net'.
In drivers/net/vxlan.c, vxlan_find_vni() added a 'flags' parameter
in 'net-next' whereas in 'net' there was a bug fix to pass in the
correct network namespace pointer in calls to this function.
Signed-off-by: David S. Miller <davem@davemloft.net>
Some existing rhashtable users get too intimate with it by walking
the buckets directly. This prevents us from easily changing the
internals of rhashtable.
This patch adds the helpers rhashtable_walk_init/exit/start/next/stop
which will replace these custom walkers.
They are meant to be usable for both procfs seq_file walks as well
as walking by a netlink dump. The iterator structure should fit
inside a netlink dump cb structure, with at least one element to
spare.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current being_destroyed check in rhashtable_expand is not
enough since if we start a shrinking process after freeing all
elements in the table that's also going to crash.
This patch adds a being_destroyed check to the deferred worker
thread so that we bail out as soon as we take the lock.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
it has just verified that it asks no more than the length of the
first segment of iovec.
And with that the last user of stuff in lib/iovec.c is gone.
RIP.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Just like for AVX2 (which simply needs an #if -> #ifdef conversion),
SSSE3 assembler support should be checked for before using it.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Jim Kukunas <james.t.kukunas@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Allow the selftest on the resizable hash table to be built modular, just
like all other tests that do not depend on DEBUG_KERNEL.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixed commit added from64to32 under _#ifndef do_csum_ but used it
under _#ifndef csum_tcpudp_nofold_, breaking some builds (Fengguang's
robot reported TILEGX's). Move from64to32 under the latter.
Fixes: 150ae0e946 ("lib/checksum.c: fix carry in csum_tcpudp_nofold")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the kernel is compiled with function tracer support the -pg compile option
is passed to gcc to generate extra code into the prologue of each function.
This patch replaces the "open-coded" -pg compile flag with a CC_FLAGS_FTRACE
makefile variable which architectures can override if a different option
should be used for code generation.
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The carry from the 64->32bits folding was dropped, e.g with:
saddr=0xFFFFFFFF daddr=0xFF0000FF len=0xFFFF proto=0 sum=1,
csum_tcpudp_nofold returned 0 instead of 1.
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As removals can occur during resizes, entries may be referred to from
both tbl and future_tbl when the removal is requested. Therefore
rhashtable_remove() must unlink the entry in both tables if this is
the case. The existing code did search both tables but stopped when it
hit the first match.
Failing to unlink in both tables resulted in use after free.
Fixes: 97defe1ecf ("rhashtable: Per bucket locks & deferred expansion/shrinking")
Reported-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can be more aggressive about this, if we are clever and careful. This is subtle.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Virtio drivers should map the part of the BAR they need, not necessarily
all of it.
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Pull RCU updates from Paul E. McKenney:
- Documentation updates.
- Miscellaneous fixes.
- Preemptible-RCU fixes, including fixing an old bug in the
interaction of RCU priority boosting and CPU hotplug.
- SRCU updates.
- RCU CPU stall-warning updates.
- RCU torture-test updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When we put our declared work task in the global workqueue with
schedule_delayed_work(), its delay parameter is always zero.
Therefore, we should define a regular work in rhashtable structure
instead of a delayed work.
By the way, we add a condition to check whether resizing functions
are NULL before cancelling the work, avoiding to cancel an
uninitialized work.
Lastly, while we wait for all work items we submitted before to run
to completion with cancel_delayed_work(), ht->mutex has been taken in
rhashtable_destroy(). Moreover, cancel_delayed_work() doesn't return
until all work items are accomplished, and when work items are
scheduled, the work's function - rht_deferred_worker() will be called.
However, as rht_deferred_worker() also needs to acquire the lock,
deadlock might happen at the moment as the lock is already held before.
So if the cancel work function is moved out of the lock covered scope,
this will avoid the deadlock.
Fixes: 97defe1 ("rhashtable: Per bucket locks & deferred expansion/shrinking")
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Thomas Graf <tgraf@suug.ch>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/xen-netfront.c
Minor overlapping changes in xen-netfront.c, mostly to do
with some buffer management changes alongside the split
of stats into TX and RX.
Signed-off-by: David S. Miller <davem@davemloft.net>
If u and v both represent negative integers and their limb counts
happen to differ, mpi_cmp will always return a positive value - this
is obviously bogus. u is smaller than v if and only if it is larger in
absolute value.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
The macro MPN_COPY_INCR this occurs in isn't used anywhere.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
The condition preceding 'return 1;' makes my head hurt. At this point,
we know that u and v have the same sign; if they are negative, they
compare opposite to how their absolute values compare (which
mpihelp_cmp found for us), otherwise cmp itself is the
answer. Negating cmp is ok since mpihelp_cmp returns {-1,0,1};
-INT_MIN==INT_MIN won't bite us.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Each per bucket lock covers a configurable number of buckets. While
shrinking, two buckets in the old table contain entries for a single
bucket in the new table. We need to lock down both while linking.
Check if they are protected by different locks to avoid a recursive
lock.
Fixes: 97defe1e ("rhashtable: Per bucket locks & deferred expansion/shrinking")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a new function called rhashtable_lookup_compare_insert()
which is very similar to rhashtable_lookup_insert(). But the former
makes use of users' given compare function to look for an object,
and then inserts it into hash table if found. As the entire process
of search and insertion is under protection of per bucket lock, this
can help users to avoid the involvement of extra lock.
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Thomas Graf <tgraf@suug.ch>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cleanups
kdb: Remove unused command flags, repeat flags and KDB_REPEAT_NONE
Fixes
kgdb/kdb: Allow access on a single core, if a CPU round up is deemed
impossible, which will allow inspection of the now "trashed" kernel
kdb: Add enable mask for the command groups
kdb: access controls to restrict sensitive commands
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Merge tag 'for_linus-3.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb
Pull kgdb/kdb fixes from Jason Wessel:
"These have been around since 3.17 and in kgdb-next for the last 9
weeks and some will go back to -stable.
Summary of changes:
Cleanups
- kdb: Remove unused command flags, repeat flags and KDB_REPEAT_NONE
Fixes
- kgdb/kdb: Allow access on a single core, if a CPU round up is
deemed impossible, which will allow inspection of the now "trashed"
kernel
- kdb: Add enable mask for the command groups
- kdb: access controls to restrict sensitive commands"
* tag 'for_linus-3.19-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb:
kernel/debug/debug_core.c: Logging clean-up
kgdb: timeout if secondary CPUs ignore the roundup
kdb: Allow access to sensitive commands to be restricted by default
kdb: Add enable mask for groups of commands
kdb: Categorize kdb commands (similar to SysRq categorization)
kdb: Remove KDB_REPEAT_NONE flag
kdb: Use KDB_REPEAT_* values as flags
kdb: Rename kdb_register_repeat() to kdb_register_flags()
kdb: Rename kdb_repeat_t to kdb_cmdflags_t, cmd_repeat to cmd_flags
kdb: Remove currently unused kdbtab_t->cmd_flags
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Thomas Graf <tgraf@suug.ch>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Thomas Graf