For a message pool message, preallocate a page, just like we do for
osd_op. For a normal message, take ceph_object_id into account and
don't bother subtracting CEPH_OSD_SLAB_OPS ceph_osd_ops.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The size of ->r_request and ->r_reply messages depends on the size of
the object name (ceph_object_id), while the size of ceph_osd_request is
fixed. Move message allocation into a separate function that would
have to be called after ceph_object_id and ceph_object_locator (which
is also going to become variable in size with RADOS namespaces) have
been filled in:
req = ceph_osdc_alloc_request(...);
<fill in req->r_base_oid>
<fill in req->r_base_oloc>
ceph_osdc_alloc_messages(req);
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
ceph_osdc_build_request() is going away. Grab snapc and initialize
->r_snapid in ceph_osdc_alloc_request().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
By the time we get to checking for_each_obj_request_safe(img_request)
terminating condition, all obj_requests may be complete and img_request
ref, that rbd_img_request_submit() takes away from its caller, may be
put. Moving the next_obj_request cursor is then a use-after-free on
img_request.
It's totally benign, as the value that's read is never used, but
I think it's still worth fixing.
Cc: Alex Elder <elder@linaro.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull x86 fix from Thomas Gleixner:
"Just the missing compat entry for the new pread/writev2"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Use compat version for preadv2 and pwritev2
Original implementation commit e54bcde3d6 ("arm64: eBPF JIT compiler")
had the relevant code paths, but due to an oversight always fail jiting.
As a result, we had been falling back to BPF interpreter whenever a BPF
program has JMP_JSET_{X,K} instructions.
With this fix, we confirm that the corresponding tests in lib/test_bpf
continue to pass, and also jited.
...
[ 2.784553] test_bpf: #30 JSET jited:1 188 192 197 PASS
[ 2.791373] test_bpf: #31 tcpdump port 22 jited:1 325 677 625 PASS
[ 2.808800] test_bpf: #32 tcpdump complex jited:1 323 731 991 PASS
...
[ 3.190759] test_bpf: #237 JMP_JSET_K: if (0x3 & 0x2) return 1 jited:1 110 PASS
[ 3.192524] test_bpf: #238 JMP_JSET_K: if (0x3 & 0xffffffff) return 1 jited:1 98 PASS
[ 3.211014] test_bpf: #249 JMP_JSET_X: if (0x3 & 0x2) return 1 jited:1 120 PASS
[ 3.212973] test_bpf: #250 JMP_JSET_X: if (0x3 & 0xffffffff) return 1 jited:1 89 PASS
...
Fixes: e54bcde3d6 ("arm64: eBPF JIT compiler")
Signed-off-by: Zi Shen Lim <zlim.lnx@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, when creating or updating a route, no check is performed
in both ipv4 and ipv6 code to the hoplimit value.
The caller can i.e. set hoplimit to 256, and when such route will
be used, packets will be sent with hoplimit/ttl equal to 0.
This commit adds checks for the RTAX_HOPLIMIT value, in both ipv4
ipv6 route code, substituting any value greater than 255 with 255.
This is consistent with what is currently done for ADVMSS and MTU
in the ipv4 code.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The slab name ends up being visible in the directory structure under
/sys, and even if you don't have access rights to the file you can see
the filenames.
Just use a 64-bit counter instead of the pointer to the 'net' structure
to generate a unique name.
This code will go away in 4.7 when the conntrack code moves to a single
kmemcache, but this is the backportable simple solution to avoiding
leaking kernel pointers to user space.
Fixes: 5b3501faa8 ("netfilter: nf_conntrack: per netns nf_conntrack_cachep")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull vfs fixes from Al Viro:
"Overlayfs fixes from Miklos, assorted fixes from me.
Stable fodder of varying severity, all sat in -next for a while"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ovl: ignore permissions on underlying lookup
vfs: add lookup_hash() helper
vfs: rename: check backing inode being equal
vfs: add vfs_select_inode() helper
get_rock_ridge_filename(): handle malformed NM entries
ecryptfs: fix handling of directory opening
atomic_open(): fix the handling of create_error
fix the copy vs. map logics in blk_rq_map_user_iov()
do_splice_to(): cap the size before passing to ->splice_read()
This patch fixes SG_RX_DV_GATE_REG_0_ADDR register offset
and ring state field lengths.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes the race condition on updating the statistics
counters by moving the counters to the ring structure.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch addresses ununiform latency across queues by adding
more queues to match with, upto number of CPU cores.
Also, number of interrupts are increased and the channel numbers
are reordered.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since hardware doesn't allow sharing of interrupts,
this patch fixes the same by removing IRQF_SHARED flag.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes the crash observed during IPv4 forward test by
setting the drop field in the dbptr.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull cgroup fixes from Tejun Heo:
"During v4.6-rc1 cgroup namespace support was merged. There is an
issue where it's impossible to tell whether a given cgroup mount point
is bind mounted or namespaced. Serge has been working on the issue
but it took longer than expected to resolve, so the late pull request.
Given that it's a completely new feature and the patches don't touch
anything else, the risk seems acceptable. However, if this is too
late, an alternative is plugging new cgroup ns creation for v4.6 and
retrying for v4.7"
* 'for-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: fix compile warning
kernfs: kernfs_sop_show_path: don't return 0 after seq_dentry call
cgroup, kernfs: make mountinfo show properly scoped path for cgroup namespaces
kernfs_path_from_node_locked: don't overwrite nlen
Pull workqueue fix from Tejun Heo:
"CPU hotplug callbacks can invoke DOWN_FAILED w/o preceding
DOWN_PREPARE which can trigger a WARN_ON() in workqueue.
The bug has been there for a very long time. It only triggers if CPU
down fails at a specific point and I don't think it has adverse
effects other than the warning messages. The fix is very low impact"
* 'for-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: fix rebind bound workers warning
Pull scheduler fix from Ingo Molnar:
"This is a revert to fix an interactivity problem.
The proper fixes for the problems that the reverted commit exposed are
now in sched/core (consisting of 3 patches), but were too risky for
v4.6 and will arrive in the v4.7 merge window"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "sched/fair: Fix fairness issue on migration"
Pull perf fixes from Ingo Molnar:
"An uncharacteristically large number of bugs popped up in the last
week:
- various tooling fixes, two crashes and build problems
- two Intel PT fixes
- an KNL uncore driver fix
- an Intel PMU driver fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf stat: Fallback to user only counters when perf_event_paranoid > 1
perf evsel: Handle EACCESS + perf_event_paranoid=2 in fallback()
perf evsel: Improve EPERM error handling in open_strerror()
tools lib traceevent: Do not reassign parg after collapse_tree()
perf probe: Check if dwarf_getlocations() is available
perf dwarf: Guard !x86_64 definitions under #ifdef else clause
perf tools: Use readdir() instead of deprecated readdir_r()
perf thread_map: Use readdir() instead of deprecated readdir_r()
perf script: Use readdir() instead of deprecated readdir_r()
perf tools: Use readdir() instead of deprecated readdir_r()
perf/core: Disable the event on a truncated AUX record
perf/x86/intel/pt: Generate PMI in the STOP region as well
perf/x86: Fix undefined shift on 32-bit kernels
perf/x86/msr: Fix SMI overflow
perf/x86/intel/uncore: Fix CHA registers configuration procedure for Knights Landing platform
perf diff: Fix duplicated output column
- The Atmel sama5d2 was registering the wrong NFC device type
- On Atmel sam9x5, the power management controller had an incorrect
register area size
- On ARM64 Allwinner machine was not secting the generic irqchip
code, causing build errors in some configurations
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=HPqy
-----END PGP SIGNATURE-----
Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Arnd Bergmann:
"Three more bug fixes for ARM SoCs this week:
- The Atmel sama5d2 was registering the wrong NFC device type
- On Atmel sam9x5, the power management controller had an incorrect
register area size
- On ARM64 Allwinner machine was not secting the generic irqchip
code, causing build errors in some configurations"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: dts: at91: sam9x5: Fix the memory range assigned to the PMC
arm64/sunxi: 4.6-rc1: Add dependency on generic irq chip
ARM: dts: at91: sama5d2: use "atmel,sama5d3-nfc" compatible for nfc
A small collection of driver specific fixes for the regulator
subsysetem:
- Fix handling of probe deferral for GPIO regulators.
- Fix a typo in the module alias for DA9053.
- Fix the definition of BUCK9 in the S2MPS11 driver. This change looks
larger than it is because an irregularity in the hardware means that
the macro used to define bucks 6-10 needs duplicating and tweaking
to have a separate macro for 9.
- Fix a series of errors in the definitions of the LDOs the AXP20x
regulators, some of which had always been present and some of which
were introduced in the merge window.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXNazxAAoJECTWi3JdVIfQd9EH/0x/3Era4ctuLFP/dKVg+lAQ
PDwgGRlHg1RVyEzzy1ZWqew//P7hgBo6urwFHjcczBE95e0bBhhMJERGnhya07uq
eWYfPARl1zHxEm0gOfLBDaFAW8YIaNyXiEsW/aTeViNIL9/HIAd/ZTZhJiDLPiAF
FdNs3yzBuAR5SHsnvCTXZY1d20LeQC6AC2nWUo2WrcyKKZZ0HamrSLP0lMq0OHVQ
n2h/8f1g9TcykakCStB/4D8vLKMt0OYmalh3Y/C/JGkWnhMoBTLRgktrNFh6lnh9
E0SnMXSuZbC9+mv8MLRHQft6XagDYzNq+odwSb9tfqbXqBdncOpvvVr6hLmzxGk=
=sVmG
-----END PGP SIGNATURE-----
Merge tag 'regulator-fix-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fixes from Mark Brown:
"A small collection of driver specific fixes for the regulator
subsysetem:
- Fix handling of probe deferral for GPIO regulators
- Fix a typo in the module alias for DA9053
- Fix the definition of BUCK9 in the S2MPS11 driver. This change
looks larger than it is because an irregularity in the hardware
means that the macro used to define bucks 6-10 needs duplicating
and tweaking to have a separate macro for 9
- Fix a series of errors in the definitions of the LDOs the AXP20x
regulators, some of which had always been present and some of which
were introduced in the merge window"
* tag 'regulator-fix-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: da9063: Correct module alias prefix to fix module autoloading
regulator: axp20x: Fix axp22x ldo_io registration error on cold boot
regulator: axp20x: Fix axp22x ldo_io voltage ranges
regulator: axp20x: Fix LDO4 linear voltage range
regulator: s2mps11: Fix invalid selector mask and voltages for buck9
regulator: gpio: check return value of of_get_named_gpio
This is rather too late so it'd be completely understandable if you
don't want to pull it at this point, I had thought I'd sent this earlier
but it seems I didn't. Everything has been in -next for some time now.
The main set of fixes here are mopping up some more issues with MMIO,
fixing handling of endianness configuration in DT (which just wasn't
working at all) and cases where the register and value endianness are
different.
There is also a fix for bulk register reads on SPMI.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXNaKUAAoJECTWi3JdVIfQoxEH/1DZGfeFyqhh4cdxrYz6UUr/
MbfMDR1wxNEvD4pifak6wYzQlern2Ki4J8ac72LP2OH9MYEoVs7kxESdSbqcVerc
uWQmn1qzj41hBSP5I4zmHIvYAwDry3B8mVVK9aYk+kBZLyOiw0eoMgZYyxB9cqws
pnfR4+5XHcaLGxh8QdIM7cXW1YOykXma4ivdwjwSlgWhYLGdh++j/uo9IUxqCrSa
qqxfMLPvAtEcksH8p4sJoRjibVDvzLXOvr3jMVHWyFoRGNDDB4TRiPkvydI04vYP
39pjg3c4gIAmp/RFyie1B8+zm4C+EQAkeiyH6D4jq8k9Gu6Y/XhqwFIAKtni3zg=
=k8tp
-----END PGP SIGNATURE-----
Merge tag 'regmap-fix-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap fixes from Mark Brown:
"This is rather too late so it'd be completely understandable if you
don't want to pull it at this point, I had thought I'd sent this
earlier but it seems I didn't. Everything has been in -next for some
time now.
The main set of fixes here are mopping up some more issues with MMIO,
fixing handling of endianness configuration in DT (which just wasn't
working at all) and cases where the register and value endianness are
different.
There is also a fix for bulk register reads on SPMI"
* tag 'regmap-fix-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: spmi: Fix regmap_spmi_ext_read in multi-byte case
regmap: mmio: Explicitly say little endian is the defualt in the bus config
regmap: mmio: Parse endianness definitions from DT
regmap: Fix implicit inclusion of device.h
regmap: mmio: Fix value endianness selection
regmap: fix documentation to match code
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=PEbo
-----END PGP SIGNATURE-----
Merge tag 'media/v4.6-6' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media fix from Mauro Carvalho Chehab:
"A revert fixing a breakage that caused an OOPS on all VB2-based DVB
drivers.
We already have a proper fix, but it sounds safer to keep it being
tested for a while and not hurry, to avoid the risk of another
regression, specially since this is meant to be c/c to stable. So,
for now, let's just revert the broken patch"
* tag 'media/v4.6-6' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
Revert "[media] videobuf2-v4l2: Verify planes array in buffer dequeueing"
Pull drm fixes from Dave Airlie:
"A bunch of radeon displayport mode setting fixes, and some misc i915
fixes.
There is one revert, the MST audio code in i915 was causing some
oopses, so we've decided just to drop it until next kernel when we can
fix it properly"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/amdgpu: fix DP mode validation
drm/radeon: fix DP mode validation
drm/i915: Bail out of pipe config compute loop on LPT
drm/radeon: fix PLL sharing on DCE6.1 (v2)
drm/radeon: fix DP link training issue with second 4K monitor
Revert "drm/i915: start adding dp mst audio"
drm/i915/bdw: Add missing delay during L3 SQC credit programming
drm/i915/lvds: separate border enable readout from panel fitter
drm/i915: Update CDCLK_FREQ register on BDW after changing cdclk frequency
Pull crypto fix from Herbert Xu:
"This fixes a bug in the RSA self-test that may cause crashes on some
architectures such as SPARC"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: testmgr - Use kmalloc memory for RSA input
Patch 562abd39 "xen-netback: support multiple extra info fragments
passed from frontend" contained a mistake which can result in an in-
correct number of responses being generated when handling errors
encountered when processing packets containing extra info fragments.
This patch fixes the problem.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reported-by: Jan Beulich <JBeulich@suse.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
User visible:
- Fallback to usermode only counters when perf_event_paranoid > 1, which
is the case now (Arnaldo Carvalho de Melo)
- Do not reassign parg after collapse_tree() in libtraceevent, which
may cause tool crashes (Steven Rostedt)
Build fixes:
- Fix the build on Fedora Rawhide, where readdir_r() is deprecated and
also wrt -Werror=unused-const-variable= + x86_32_regoffset_table on
!x86_64 (Arnaldo Carvalho de Melo)
- Fix the build on Ubuntu 12.04.5, where dwarf_getlocations() isn't
available, i.e. libdw-dev < 0.157 (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=qn4a
-----END PGP SIGNATURE-----
Merge tag 'perf-urgent-for-mingo-20160512' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
- Fallback to usermode-only counters when perf_event_paranoid > 1, which
is the case now (Arnaldo Carvalho de Melo)
- Do not reassign parg after collapse_tree() in libtraceevent, which
may cause tool crashes (Steven Rostedt)
- Fix the build on Fedora Rawhide, where readdir_r() is deprecated and
also wrt -Werror=unused-const-variable= + x86_32_regoffset_table on
!x86_64 (Arnaldo Carvalho de Melo)
- Fix the build on Ubuntu 12.04.5, where dwarf_getlocations() isn't
available, i.e. libdw-dev < 0.157 (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge fixes from Andrew Morton:
"4 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: thp: calculate the mapcount correctly for THP pages during WP faults
ksm: fix conflict between mmput and scan_get_next_rmap_item
ocfs2: fix posix_acl_create deadlock
ocfs2: revert using ocfs2_acl_chmod to avoid inode cluster lock hang
This will provide fully accuracy to the mapcount calculation in the
write protect faults, so page pinning will not get broken by false
positive copy-on-writes.
total_mapcount() isn't the right calculation needed in
reuse_swap_page(), so this introduces a page_trans_huge_mapcount()
that is effectively the full accurate return value for page_mapcount()
if dealing with Transparent Hugepages, however we only use the
page_trans_huge_mapcount() during COW faults where it strictly needed,
due to its higher runtime cost.
This also provide at practical zero cost the total_mapcount
information which is needed to know if we can still relocate the page
anon_vma to the local vma. If page_trans_huge_mapcount() returns 1 we
can reuse the page no matter if it's a pte or a pmd_trans_huge
triggering the fault, but we can only relocate the page anon_vma to
the local vma->anon_vma if we're sure it's only this "vma" mapping the
whole THP physical range.
Kirill A. Shutemov discovered the problem with moving the page
anon_vma to the local vma->anon_vma in a previous version of this
patch and another problem in the way page_move_anon_rmap() was called.
Andrew Morton discovered that CONFIG_SWAP=n wouldn't build in a
previous version, because reuse_swap_page must be a macro to call
page_trans_huge_mapcount from swap.h, so this uses a macro again
instead of an inline function. With this change at least it's a less
dangerous usage than it was before, because "page" is used only once
now, while with the previous code reuse_swap_page(page++) would have
called page_mapcount on page+1 and it would have increased page twice
instead of just once.
Dean Luick noticed an uninitialized variable that could result in a
rmap inefficiency for the non-THP case in a previous version.
Mike Marciniszyn said:
: Our RDMA tests are seeing an issue with memory locking that bisects to
: commit 61f5d698cc ("mm: re-enable THP")
:
: The test program registers two rather large MRs (512M) and RDMA
: writes data to a passive peer using the first and RDMA reads it back
: into the second MR and compares that data. The sizes are chosen randomly
: between 0 and 1024 bytes.
:
: The test will get through a few (<= 4 iterations) and then gets a
: compare error.
:
: Tracing indicates the kernel logical addresses associated with the individual
: pages at registration ARE correct , the data in the "RDMA read response only"
: packets ARE correct.
:
: The "corruption" occurs when the packet crosse two pages that are not physically
: contiguous. The second page reads back as zero in the program.
:
: It looks like the user VA at the point of the compare error no longer points to
: the same physical address as was registered.
:
: This patch totally resolves the issue!
Link: http://lkml.kernel.org/r/1462547040-1737-2-git-send-email-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Reviewed-by: Dean Luick <dean.luick@intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Tested-by: Josh Collier <josh.d.collier@intel.com>
Cc: Marc Haber <mh+linux-kernel@zugschlus.de>
Cc: <stable@vger.kernel.org> [4.5]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A concurrency issue about KSM in the function scan_get_next_rmap_item.
task A (ksmd): |task B (the mm's task):
|
mm = slot->mm; |
down_read(&mm->mmap_sem); |
|
... |
|
spin_lock(&ksm_mmlist_lock); |
|
ksm_scan.mm_slot go to the next slot; |
|
spin_unlock(&ksm_mmlist_lock); |
|mmput() ->
| ksm_exit():
|
|spin_lock(&ksm_mmlist_lock);
|if (mm_slot && ksm_scan.mm_slot != mm_slot) {
| if (!mm_slot->rmap_list) {
| easy_to_free = 1;
| ...
|
|if (easy_to_free) {
| mmdrop(mm);
| ...
|
|So this mm_struct may be freed in the mmput().
|
up_read(&mm->mmap_sem); |
As we can see above, the ksmd thread may access a mm_struct that already
been freed to the kmem_cache. Suppose a fork will get this mm_struct from
the kmem_cache, the ksmd thread then call up_read(&mm->mmap_sem), will
cause mmap_sem.count to become -1.
As suggested by Andrea Arcangeli, unmerge_and_remove_all_rmap_items has
the same SMP race condition, so fix it too. My prev fix in function
scan_get_next_rmap_item will introduce a different SMP race condition, so
just invert the up_read/spin_unlock order as Andrea Arcangeli said.
Link: http://lkml.kernel.org/r/1462708815-31301-1-git-send-email-zhouchengming1@huawei.com
Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com>
Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Geliang Tang <geliangtang@163.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Ding Tianhong <dingtianhong@huawei.com>
Cc: Li Bin <huawei.libin@huawei.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 702e5bc68a ("ocfs2: use generic posix ACL infrastructure")
refactored code to use posix_acl_create. The problem with this function
is that it is not mindful of the cluster wide inode lock making it
unsuitable for use with ocfs2 inode creation with ACLs. For example,
when used in ocfs2_mknod, this function can cause deadlock as follows.
The parent dir inode lock is taken when calling posix_acl_create ->
get_acl -> ocfs2_iop_get_acl which takes the inode lock again. This can
cause deadlock if there is a blocked remote lock request waiting for the
lock to be downconverted. And same deadlock happened in ocfs2_reflink.
This fix is to revert back using ocfs2_init_acl.
Fixes: 702e5bc68a ("ocfs2: use generic posix ACL infrastructure")
Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com>
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 743b5f1434 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
introduced this issue. ocfs2_setattr called by chmod command holds
cluster wide inode lock when calling posix_acl_chmod. This latter
function in turn calls ocfs2_iop_get_acl and ocfs2_iop_set_acl. These
two are also called directly from vfs layer for getfacl/setfacl commands
and therefore acquire the cluster wide inode lock. If a remote
conversion request comes after the first inode lock in ocfs2_setattr,
OCFS2_LOCK_BLOCKED will be set. And this will cause the second call to
inode lock from the ocfs2_iop_get_acl() to block indefinetly.
The deleted version of ocfs2_acl_chmod() calls __posix_acl_chmod() which
does not call back into the filesystem. Therefore, we restore
ocfs2_acl_chmod(), modify it slightly for locking as needed, and use that
instead.
Fixes: 743b5f1434 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com>
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I tried to fix this before, but my previous fix was incomplete
and we can still get the same link error in randconfig builds
because of the way that Kconfig treats the
default y if MVNETA=y && MVNETA_BM_ENABLE
line that does not actually trigger when MVNETA_BM_ENABLE=m,
unlike I intended.
Changing the line to use MVNETA_BM_ENABLE!=n however has
the desired effect and hopefully makes all configurations
work as expected.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 019ded3aa7 ("net: mvneta: bm: clarify dependencies")
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a pretty boring pull request as you wish: including a few
small and trivial HD-audio and USB-audio quirks and a couple of small
regression fixes in HD-audio.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iQIcBAABCAAGBQJXNE/uAAoJEGwxgFQ9KSmk2DAP/1GfWZXzZRMGeGX3uylffRJP
S7BeZeVl6xHrzZfkteZYMDc3+B1Ebj0h+oS1AQftOu836q5JTYbTf4dfzaG9J4YK
g1ZveP+fkAlSiRDzeRa1+iNHl/tUk4fqLhkN0FDIinhEnHegIKgXZd3N+GToOR81
zuZLCEjzmrmm3mDGH0uQ+jDfDDnTTT9bJC+uh61CjDnH6OaeLjVc/lVhdo2tYtaV
SwqmCa+hD/CfSEDT5Ui/iD+0g8GCerxyTLzdA6A8mQ01SuLzq9QmRw4yb6s/raeO
jHMGHUsacMLyAITmKZPxGQQnzmGsGZn5Uc2ia/HgLWmCRohnjZXxhx2QzGUJs9BL
Z45njkULibUFqMlNrsfQ70BvZICEi4SddnSpVPV6BlHX1BCRec/EGgXqyKMqt7aA
pSg+2NCDUVpuLC2pLw3So0ND3uJvFXQ2yHA4WuH8kbbXfAXCxLvHj/Sf5xvXC9Ty
XN0C/NU4V2JTlUbCDnNUknToYszF/WN/k73HjInRUWakLsTFwmssiOVLYixOFDiL
h/fPp889Uykl20YfmVXV3bQNRukJxwLCQpQR6o7HOyYaldMoja3Pky2AhSF8EWfB
XZPf9rhF6VWKjsiH83oWXjBfqd/Uh62MEXehGkjlvqbSPjBtyjXSPFPUzVvY+WIX
03t6MfqOBRaLRgkIMHEc
=lhNO
-----END PGP SIGNATURE-----
Merge tag 'sound-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"This is a pretty boring pull request as you wish: including a few
small and trivial HD-audio and USB-audio quirks and a couple of small
regression fixes in HD-audio"
* tag 'sound-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: usb-audio: Yet another Phoneix Audio device quirk
ALSA: hda - Fix regression on ATI HDMI audio
ALSA: hda - Fix subwoofer pin on ASUS N751 and N551
ALSA: hda - Fix broken reconfig
ALSA: hda - Fix white noise on Asus UX501VW headset
ALSA: usb-audio: Quirk for yet another Phoenix Audio devices (v2)
After 0161028b7c ("perf/core: Change the default paranoia level to 2")
'perf stat' fails for users without CAP_SYS_ADMIN, so just use
'perf_evsel__fallback()' to have the same behaviour as 'perf record',
i.e. set perf_event_attr.exclude_kernel to 1.
Now:
[acme@jouet linux]$ perf stat usleep 1
Performance counter stats for 'usleep 1':
0.352536 task-clock:u (msec) # 0.423 CPUs utilized
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
49 page-faults:u # 0.139 M/sec
309,407 cycles:u # 0.878 GHz
243,791 instructions:u # 0.79 insn per cycle
49,622 branches:u # 140.757 M/sec
3,884 branch-misses:u # 7.83% of all branches
0.000834174 seconds time elapsed
[acme@jouet linux]$
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-b20jmx4dxt5hpaa9t2rroi0o@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now with the default for the kernel.perf_event_paranoid sysctl being 2 [1]
we need to fall back to :u, i.e. to set perf_event_attr.exclude_kernel
to 1.
Before:
[acme@jouet linux]$ perf record usleep 1
Error:
You may not have permission to collect stats.
Consider tweaking /proc/sys/kernel/perf_event_paranoid,
which controls use of the performance events system by
unprivileged users (without CAP_SYS_ADMIN).
The current value is 2:
-1: Allow use of (almost) all events by all users
>= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK
>= 1: Disallow CPU event access by users without CAP_SYS_ADMIN
>= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN
[acme@jouet linux]$
After:
[acme@jouet linux]$ perf record usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.016 MB perf.data (7 samples) ]
[acme@jouet linux]$ perf evlist
cycles:u
[acme@jouet linux]$ perf evlist -v
cycles:u: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, exclude_kernel: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
[acme@jouet linux]$
And if the user turns on verbose mode, an explanation will appear:
[acme@jouet linux]$ perf record -v usleep 1
Warning:
kernel.perf_event_paranoid=2, trying to fall back to excluding kernel samples
mmap size 528384B
[ perf record: Woken up 1 times to write data ]
Looking at the vmlinux_path (8 entries long)
Using /lib/modules/4.6.0-rc7+/build/vmlinux for symbols
[ perf record: Captured and wrote 0.016 MB perf.data (7 samples) ]
[acme@jouet linux]$
[1] 0161028b7c ("perf/core: Change the default paranoia level to 2")
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-b20jmx4dxt5hpaa9t2rroi0o@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Switch the order of the loops to walk the rates on the top
so we exhaust all DP 1.1 rate/lane combinations before trying
DP 1.2 rate/lane combos.
This avoids selecting rates that are supported by the monitor,
but not the connector leading to valid modes getting rejected.
bug:
https://bugs.freedesktop.org/show_bug.cgi?id=95206
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Switch the order of the loops to walk the rates on the top
so we exhaust all DP 1.1 rate/lane combinations before trying
DP 1.2 rate/lane combos.
This avoids selecting rates that are supported by the monitor,
but not the connector leading to valid modes getting rejected.
bug:
https://bugs.freedesktop.org/show_bug.cgi?id=95206
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
We were showing a hardcoded default value for the kernel.perf_event_paranoid
sysctl, now that it became more paranoid (1 -> 2 [1]), this would need to be
updated, instead show the current value:
[acme@jouet linux]$ perf record ls
Error:
You may not have permission to collect stats.
Consider tweaking /proc/sys/kernel/perf_event_paranoid,
which controls use of the performance events system by
unprivileged users (without CAP_SYS_ADMIN).
The current value is 2:
-1: Allow use of (almost) all events by all users
>= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK
>= 1: Disallow CPU event access by users without CAP_SYS_ADMIN
>= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN
[acme@jouet linux]$
[1] 0161028b7c ("perf/core: Change the default paranoia level to 2")
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-0gc4rdpg8d025r5not8s8028@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
- The pull up/down logic for the AT91 PIO4 controller was tilted:
we need to mask the reverse pull when unmasking a pull direction.
Setting both pull up & pull down is illegal and makes no sense.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=Kzzn
-----END PGP SIGNATURE-----
Merge tag 'pinctrl-v4.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pinctrl fix from Linus Walleij:
"A single last pin control fix for v4.6. t's tagged for stable and
only hits a single driver with two added lines so should be safe.
Tested in linux-next.
- The pull up/down logic for the AT91 PIO4 controller was tilted: we
need to mask the reverse pull when unmasking a pull direction.
Setting both pull up & pull down is illegal and makes no sense"
* tag 'pinctrl-v4.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: at91-pio4: fix pull-up/down logic
------------[ cut here ]------------
WARNING: CPU: 0 PID: 16 at kernel/workqueue.c:4559 rebind_workers+0x1c0/0x1d0
Modules linked in:
CPU: 0 PID: 16 Comm: cpuhp/0 Not tainted 4.6.0-rc4+ #31
Hardware name: IBM IBM System x3550 M4 Server -[7914IUW]-/00Y8603, BIOS -[D7E128FUS-1.40]- 07/23/2013
0000000000000000 ffff881037babb58 ffffffff8139d885 0000000000000010
0000000000000000 0000000000000000 0000000000000000 ffff881037babba8
ffffffff8108505d ffff881037ba0000 000011cf3e7d6e60 0000000000000046
Call Trace:
dump_stack+0x89/0xd4
__warn+0xfd/0x120
warn_slowpath_null+0x1d/0x20
rebind_workers+0x1c0/0x1d0
workqueue_cpu_up_callback+0xf5/0x1d0
notifier_call_chain+0x64/0x90
? trace_hardirqs_on_caller+0xf2/0x220
? notify_prepare+0x80/0x80
__raw_notifier_call_chain+0xe/0x10
__cpu_notify+0x35/0x50
notify_down_prepare+0x5e/0x80
? notify_prepare+0x80/0x80
cpuhp_invoke_callback+0x73/0x330
? __schedule+0x33e/0x8a0
cpuhp_down_callbacks+0x51/0xc0
cpuhp_thread_fun+0xc1/0xf0
smpboot_thread_fn+0x159/0x2a0
? smpboot_create_threads+0x80/0x80
kthread+0xef/0x110
? wait_for_completion+0xf0/0x120
? schedule_tail+0x35/0xf0
ret_from_fork+0x22/0x50
? __init_kthread_worker+0x70/0x70
---[ end trace eb12ae47d2382d8f ]---
notify_down_prepare: attempt to take down CPU 0 failed
This bug can be reproduced by below config w/ nohz_full= all cpus:
CONFIG_BOOTPARAM_HOTPLUG_CPU0=y
CONFIG_DEBUG_HOTPLUG_CPU0=y
CONFIG_NO_HZ_FULL=y
As Thomas pointed out:
| If a down prepare callback fails, then DOWN_FAILED is invoked for all
| callbacks which have successfully executed DOWN_PREPARE.
|
| But, workqueue has actually two notifiers. One which handles
| UP/DOWN_FAILED/ONLINE and one which handles DOWN_PREPARE.
|
| Now look at the priorities of those callbacks:
|
| CPU_PRI_WORKQUEUE_UP = 5
| CPU_PRI_WORKQUEUE_DOWN = -5
|
| So the call order on DOWN_PREPARE is:
|
| CB 1
| CB ...
| CB workqueue_up() -> Ignores DOWN_PREPARE
| CB ...
| CB X ---> Fails
|
| So we call up to CB X with DOWN_FAILED
|
| CB 1
| CB ...
| CB workqueue_up() -> Handles DOWN_FAILED
| CB ...
| CB X-1
|
| So the problem is that the workqueue stuff handles DOWN_FAILED in the up
| callback, while it should do it in the down callback. Which is not a good idea
| either because it wants to be called early on rollback...
|
| Brilliant stuff, isn't it? The hotplug rework will solve this problem because
| the callbacks become symetric, but for the existing mess, we need some
| workaround in the workqueue code.
The boot CPU handles housekeeping duty(unbound timers, workqueues,
timekeeping, ...) on behalf of full dynticks CPUs. It must remain
online when nohz full is enabled. There is a priority set to every
notifier_blocks:
workqueue_cpu_up > tick_nohz_cpu_down > workqueue_cpu_down
So tick_nohz_cpu_down callback failed when down prepare cpu 0, and
notifier_blocks behind tick_nohz_cpu_down will not be called any
more, which leads to workers are actually not unbound. Then hotplug
state machine will fallback to undo and online cpu 0 again. Workers
will be rebound unconditionally even if they are not unbound and
trigger the warning in this progress.
This patch fix it by catching !DISASSOCIATED to avoid rebind bound
workers.
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: stable@vger.kernel.org
Suggested-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>