Implements freelist randomization for the SLUB allocator. It was
previous implemented for the SLAB allocator. Both use the same
configuration option (CONFIG_SLAB_FREELIST_RANDOM).
The list is randomized during initialization of a new set of pages. The
order on different freelist sizes is pre-computed at boot for
performance. Each kmem_cache has its own randomized freelist.
This security feature reduces the predictability of the kernel SLUB
allocator against heap overflows rendering attacks much less stable.
For example these attacks exploit the predictability of the heap:
- Linux Kernel CAN SLUB overflow (https://goo.gl/oMNWkU)
- Exploiting Linux Kernel Heap corruptions (http://goo.gl/EXLn95)
Performance results:
slab_test impact is between 3% to 4% on average for 100000 attempts
without smp. It is a very focused testing, kernbench show the overall
impact on the system is way lower.
Before:
Single thread testing
=====================
1. Kmalloc: Repeatedly allocate then free test
100000 times kmalloc(8) -> 49 cycles kfree -> 77 cycles
100000 times kmalloc(16) -> 51 cycles kfree -> 79 cycles
100000 times kmalloc(32) -> 53 cycles kfree -> 83 cycles
100000 times kmalloc(64) -> 62 cycles kfree -> 90 cycles
100000 times kmalloc(128) -> 81 cycles kfree -> 97 cycles
100000 times kmalloc(256) -> 98 cycles kfree -> 121 cycles
100000 times kmalloc(512) -> 95 cycles kfree -> 122 cycles
100000 times kmalloc(1024) -> 96 cycles kfree -> 126 cycles
100000 times kmalloc(2048) -> 115 cycles kfree -> 140 cycles
100000 times kmalloc(4096) -> 149 cycles kfree -> 171 cycles
2. Kmalloc: alloc/free test
100000 times kmalloc(8)/kfree -> 70 cycles
100000 times kmalloc(16)/kfree -> 70 cycles
100000 times kmalloc(32)/kfree -> 70 cycles
100000 times kmalloc(64)/kfree -> 70 cycles
100000 times kmalloc(128)/kfree -> 70 cycles
100000 times kmalloc(256)/kfree -> 69 cycles
100000 times kmalloc(512)/kfree -> 70 cycles
100000 times kmalloc(1024)/kfree -> 73 cycles
100000 times kmalloc(2048)/kfree -> 72 cycles
100000 times kmalloc(4096)/kfree -> 71 cycles
After:
Single thread testing
=====================
1. Kmalloc: Repeatedly allocate then free test
100000 times kmalloc(8) -> 57 cycles kfree -> 78 cycles
100000 times kmalloc(16) -> 61 cycles kfree -> 81 cycles
100000 times kmalloc(32) -> 76 cycles kfree -> 93 cycles
100000 times kmalloc(64) -> 83 cycles kfree -> 94 cycles
100000 times kmalloc(128) -> 106 cycles kfree -> 107 cycles
100000 times kmalloc(256) -> 118 cycles kfree -> 117 cycles
100000 times kmalloc(512) -> 114 cycles kfree -> 116 cycles
100000 times kmalloc(1024) -> 115 cycles kfree -> 118 cycles
100000 times kmalloc(2048) -> 147 cycles kfree -> 131 cycles
100000 times kmalloc(4096) -> 214 cycles kfree -> 161 cycles
2. Kmalloc: alloc/free test
100000 times kmalloc(8)/kfree -> 66 cycles
100000 times kmalloc(16)/kfree -> 66 cycles
100000 times kmalloc(32)/kfree -> 66 cycles
100000 times kmalloc(64)/kfree -> 66 cycles
100000 times kmalloc(128)/kfree -> 65 cycles
100000 times kmalloc(256)/kfree -> 67 cycles
100000 times kmalloc(512)/kfree -> 67 cycles
100000 times kmalloc(1024)/kfree -> 64 cycles
100000 times kmalloc(2048)/kfree -> 67 cycles
100000 times kmalloc(4096)/kfree -> 67 cycles
Kernbench, before:
Average Optimal load -j 12 Run (std deviation):
Elapsed Time 101.873 (1.16069)
User Time 1045.22 (1.60447)
System Time 88.969 (0.559195)
Percent CPU 1112.9 (13.8279)
Context Switches 189140 (2282.15)
Sleeps 99008.6 (768.091)
After:
Average Optimal load -j 12 Run (std deviation):
Elapsed Time 102.47 (0.562732)
User Time 1045.3 (1.34263)
System Time 88.311 (0.342554)
Percent CPU 1105.8 (6.49444)
Context Switches 189081 (2355.78)
Sleeps 99231.5 (800.358)
Link: http://lkml.kernel.org/r/1464295031-26375-3-git-send-email-thgarnie@google.com
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel heap allocators are using a sequential freelist making their
allocation predictable. This predictability makes kernel heap overflow
easier to exploit. An attacker can careful prepare the kernel heap to
control the following chunk overflowed.
For example these attacks exploit the predictability of the heap:
- Linux Kernel CAN SLUB overflow (https://goo.gl/oMNWkU)
- Exploiting Linux Kernel Heap corruptions (http://goo.gl/EXLn95)
***Problems that needed solving:
- Randomize the Freelist (singled linked) used in the SLUB allocator.
- Ensure good performance to encourage usage.
- Get best entropy in early boot stage.
***Parts:
- 01/02 Reorganize the SLAB Freelist randomization to share elements
with the SLUB implementation.
- 02/02 The SLUB Freelist randomization implementation. Similar approach
than the SLAB but tailored to the singled freelist used in SLUB.
***Performance data:
slab_test impact is between 3% to 4% on average for 100000 attempts
without smp. It is a very focused testing, kernbench show the overall
impact on the system is way lower.
Before:
Single thread testing
=====================
1. Kmalloc: Repeatedly allocate then free test
100000 times kmalloc(8) -> 49 cycles kfree -> 77 cycles
100000 times kmalloc(16) -> 51 cycles kfree -> 79 cycles
100000 times kmalloc(32) -> 53 cycles kfree -> 83 cycles
100000 times kmalloc(64) -> 62 cycles kfree -> 90 cycles
100000 times kmalloc(128) -> 81 cycles kfree -> 97 cycles
100000 times kmalloc(256) -> 98 cycles kfree -> 121 cycles
100000 times kmalloc(512) -> 95 cycles kfree -> 122 cycles
100000 times kmalloc(1024) -> 96 cycles kfree -> 126 cycles
100000 times kmalloc(2048) -> 115 cycles kfree -> 140 cycles
100000 times kmalloc(4096) -> 149 cycles kfree -> 171 cycles
2. Kmalloc: alloc/free test
100000 times kmalloc(8)/kfree -> 70 cycles
100000 times kmalloc(16)/kfree -> 70 cycles
100000 times kmalloc(32)/kfree -> 70 cycles
100000 times kmalloc(64)/kfree -> 70 cycles
100000 times kmalloc(128)/kfree -> 70 cycles
100000 times kmalloc(256)/kfree -> 69 cycles
100000 times kmalloc(512)/kfree -> 70 cycles
100000 times kmalloc(1024)/kfree -> 73 cycles
100000 times kmalloc(2048)/kfree -> 72 cycles
100000 times kmalloc(4096)/kfree -> 71 cycles
After:
Single thread testing
=====================
1. Kmalloc: Repeatedly allocate then free test
100000 times kmalloc(8) -> 57 cycles kfree -> 78 cycles
100000 times kmalloc(16) -> 61 cycles kfree -> 81 cycles
100000 times kmalloc(32) -> 76 cycles kfree -> 93 cycles
100000 times kmalloc(64) -> 83 cycles kfree -> 94 cycles
100000 times kmalloc(128) -> 106 cycles kfree -> 107 cycles
100000 times kmalloc(256) -> 118 cycles kfree -> 117 cycles
100000 times kmalloc(512) -> 114 cycles kfree -> 116 cycles
100000 times kmalloc(1024) -> 115 cycles kfree -> 118 cycles
100000 times kmalloc(2048) -> 147 cycles kfree -> 131 cycles
100000 times kmalloc(4096) -> 214 cycles kfree -> 161 cycles
2. Kmalloc: alloc/free test
100000 times kmalloc(8)/kfree -> 66 cycles
100000 times kmalloc(16)/kfree -> 66 cycles
100000 times kmalloc(32)/kfree -> 66 cycles
100000 times kmalloc(64)/kfree -> 66 cycles
100000 times kmalloc(128)/kfree -> 65 cycles
100000 times kmalloc(256)/kfree -> 67 cycles
100000 times kmalloc(512)/kfree -> 67 cycles
100000 times kmalloc(1024)/kfree -> 64 cycles
100000 times kmalloc(2048)/kfree -> 67 cycles
100000 times kmalloc(4096)/kfree -> 67 cycles
Kernbench, before:
Average Optimal load -j 12 Run (std deviation):
Elapsed Time 101.873 (1.16069)
User Time 1045.22 (1.60447)
System Time 88.969 (0.559195)
Percent CPU 1112.9 (13.8279)
Context Switches 189140 (2282.15)
Sleeps 99008.6 (768.091)
After:
Average Optimal load -j 12 Run (std deviation):
Elapsed Time 102.47 (0.562732)
User Time 1045.3 (1.34263)
System Time 88.311 (0.342554)
Percent CPU 1105.8 (6.49444)
Context Switches 189081 (2355.78)
Sleeps 99231.5 (800.358)
This patch (of 2):
This commit reorganizes the previous SLAB freelist randomization to
prepare for the SLUB implementation. It moves functions that will be
shared to slab_common.
The entropy functions are changed to align with the SLUB implementation,
now using get_random_(int|long) functions. These functions were chosen
because they provide a bit more entropy early on boot and better
performance when specific arch instructions are not available.
[akpm@linux-foundation.org: fix build]
Link: http://lkml.kernel.org/r/1464295031-26375-2-git-send-email-thgarnie@google.com
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The per-sb inode writeback list tracks inodes currently under writeback
to facilitate efficient sync processing. In particular, it ensures that
sync only needs to walk through a list of inodes that were cleaned by
the sync.
Add a couple tracepoints to help identify when inodes are added/removed
to and from the writeback lists. Piggyback off of the writeback
lazytime tracepoint template as it already tracks the relevant inode
information.
Link: http://lkml.kernel.org/r/1466594593-6757-3-git-send-email-bfoster@redhat.com
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <dchinner@redhat.com>
cc: Josef Bacik <jbacik@fb.com>
Cc: Holger Hoffstätte <holger.hoffstaette@applied-asynchrony.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
wait_sb_inodes() currently does a walk of all inodes in the filesystem
to find dirty one to wait on during sync. This is highly inefficient
and wastes a lot of CPU when there are lots of clean cached inodes that
we don't need to wait on.
To avoid this "all inode" walk, we need to track inodes that are
currently under writeback that we need to wait for. We do this by
adding inodes to a writeback list on the sb when the mapping is first
tagged as having pages under writeback. wait_sb_inodes() can then walk
this list of "inodes under IO" and wait specifically just for the inodes
that the current sync(2) needs to wait for.
Define a couple helpers to add/remove an inode from the writeback list
and call them when the overall mapping is tagged for or cleared from
writeback. Update wait_sb_inodes() to walk only the inodes under
writeback due to the sync.
With this change, filesystem sync times are significantly reduced for
fs' with largely populated inode caches and otherwise no other work to
do. For example, on a 16xcpu 2GHz x86-64 server, 10TB XFS filesystem
with a ~10m entry inode cache, sync times are reduced from ~7.3s to less
than 0.1s when the filesystem is fully clean.
Link: http://lkml.kernel.org/r/1466594593-6757-2-git-send-email-bfoster@redhat.com
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Tested-by: Holger Hoffstätte <holger.hoffstaette@applied-asynchrony.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clean up unnecessary assignment for 'ret'.
Link: http://lkml.kernel.org/r/578C61F6.4080403@huawei.com
Signed-off-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These BUG_ON(!inode) are obscure because we have already used inode to
get osb. And actually we can guarantee here inode is valid in the
context. So we can safely remove them.
Link: http://lkml.kernel.org/r/5776336A.6030104@huawei.com
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Eric Ren <zren@suse.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Several prototypes in inode.h are just defined but not actually
implemented and used, so remove them.
Link: http://lkml.kernel.org/r/57763787.4020706@huawei.com
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dlm_debug_ctxt->debug_refcnt is initialized to 1 and then increased to 2
by dlm_debug_get in dlm_debug_init. But dlm_debug_put is called only
once in dlm_debug_shutdown during unregister dlm, which leads to
dlm_debug_ctxt leaked.
Link: http://lkml.kernel.org/r/577BB755.4030900@huawei.com
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Jiufei Xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The last goto is unneeded, so remove it.
Link: http://lkml.kernel.org/r/576213D3.6080002@huawei.com
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Journal replay will be run when performing recovery for a dead node. To
avoid the stale cache impact, all blocks of dead node's journal inode
were reloaded from disk. This hurts the performance. Check whether one
block is cached before reloading it can improve performance a lot. In
my test env, the time doing recovery was improved from 120s to 1s.
[akpm@linux-foundation.org: clean up the for loop p_blkno handling]
Link: http://lkml.kernel.org/r/1466155682-24656-1-git-send-email-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: "Gang He" <ghe@suse.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Obviously, memset() has zeroed the whole struct locking_max_version.
So, it's no need to zero its two fields individually.
Link: http://lkml.kernel.org/r/1463970605-18354-1-git-send-email-zren@suse.com
Signed-off-by: Eric Ren <zren@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Gang He <ghe@suse.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add ':' to fix trivial kernel-doc warning in <linux/debugobjects.h>:
..//include/linux/debugobjects.h:63: warning: No description found for parameter 'is_static_object'
Link: http://lkml.kernel.org/r/575B01B8.5060600@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We are having build failure with m32r and the error message being:
ERROR: "__ucmpdi2" [lib/842/842_decompress.ko] undefined!
ERROR: "__ucmpdi2" [fs/btrfs/btrfs.ko] undefined!
ERROR: "__ucmpdi2" [drivers/scsi/sd_mod.ko] undefined!
ERROR: "__ucmpdi2" [drivers/media/i2c/adv7842.ko] undefined!
ERROR: "__ucmpdi2" [drivers/md/bcache/bcache.ko] undefined!
ERROR: "__ucmpdi2" [drivers/iio/imu/inv_mpu6050/inv-mpu6050.ko] undefined!
__ucmpdi2 is introduced to m32r architecture taking example from other
architectures like h8300, microblaze, mips.
Link: http://lkml.kernel.org/r/1465509213-4280-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Python divisions are integer divisions unless at least one parameter is
a float. The current bloat-o-meter fails to print sub-percentage
changes:
Total: Before=10515408, After=10604060, chg 0.000000%
Force float division by using one float and pretty the print to two
significant decimals:
Total: Before=10515408, After=10604060, chg +0.84%
Link: http://lkml.kernel.org/r/1465980311-23814-1-git-send-email-riku.voipio@linaro.org
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Before, the stack protector flag was sanity checked before .config had
been reprocessed. This meant the build couldn't be aborted early, and
only a warning could be emitted followed later by the compiler blowing
up with an unknown flag. This has caused a lot of confusion over time,
so this splits the flag selection from sanity checking and performs the
sanity checking after the make has been restarted from a reprocessed
.config, so builds can be aborted as early as possible now.
Additionally moves the x86-specific sanity check to the same location,
since it suffered from the same warn-then-wait-for-compiler-failure
problem.
Link: http://lkml.kernel.org/r/20160712223043.GA11664@www.outflux.net
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When building with "make W=1", we get a warning about an empty stub
function that does nothing but reassign its one of its arguments:
drivers/video/fbdev/core/fbmon.c: In function 'fb_edid_to_monspecs':
drivers/video/fbdev/core/fbmon.c:1497:67: error: parameter 'specs' set but not used [-Werror=unused-but-set-parameter]
We can simply make that function completely empty to avoid the warning.
This prevents a warning which everyone will see after "CFLAGS: add
-Wunused-but-set-parameter" is merged.
Link: http://lkml.kernel.org/r/20160715203229.1771162-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
get_hash_bucket() and put_hash_bucket() acquire and release the same
spinlock, but this confuses static checkers such as sparse
lib/dma-debug.c:254:27: warning: context imbalance in 'get_hash_bucket' - wrong count at exit
lib/dma-debug.c:268:13: warning: context imbalance in 'put_hash_bucket' - unexpected unlock
Add the appropriate acquire and release statements so that checkers can
properly track the lock state.
Link: http://lkml.kernel.org/r/20160701191552.24295-1-sboyd@codeaurora.org
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the unused wrappers dax_fault() and dax_pmd_fault(). After this
removal, rename __dax_fault() and __dax_pmd_fault() to dax_fault() and
dax_pmd_fault() respectively, and update all callers.
The dax_fault() and dax_pmd_fault() wrappers were initially intended to
capture some filesystem independent functionality around page faults
(calling sb_start_pagefault() & sb_end_pagefault(), updating file mtime
and ctime).
However, the following commits:
5726b27b09 ("ext2: Add locking for DAX faults")
ea3d7209ca ("ext4: fix races between page faults and hole punching")
added locking to the ext2 and ext4 filesystems after these common
operations but before __dax_fault() and __dax_pmd_fault() were called.
This means that these wrappers are no longer used, and are unlikely to
be used in the future.
XFS has had locking analogous to what was recently added to ext2 and
ext4 since DAX support was initially introduced by:
6b698edeee ("xfs: add DAX file operations support")
Link: http://lkml.kernel.org/r/20160714214049.20075-2-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These are originally from Matthew Wilcox and were part of his huge
"mm,fs,dax: Change ->pmd_fault to ->huge_fault" patch that was part of
PUD support.
I'm breaking these small changes out as they stand on their own and add
useful information to Documentation/filesystems/dax.txt.
Link: http://lkml.kernel.org/r/20160714214049.20075-1-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
PGALLOC_GFP uses __GFP_REPEAT but none of the allocation which uses this
flag is for more than order-2. This means that this flag has never been
actually useful here because it has always been used only for
PAGE_ALLOC_COSTLY requests.
Link: http://lkml.kernel.org/r/1464599699-30131-5-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.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>
Pull irq updates from Thomas Gleixner:
"The irq department delivers:
- new core infrastructure to allow better management of multi-queue
devices (interrupt spreading, node aware descriptor allocation ...)
- a new interrupt flow handler to support the new fangled Intel VMD
devices.
- yet another new interrupt controller driver.
- a series of fixes which addresses sparse warnings, missing
includes, missing static declarations etc from Ben Dooks.
- a fix for the error handling in the hierarchical domain allocation
code.
- the usual pile of small updates to core and driver code"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
genirq: Fix missing irq allocation affinity hint
irqdomain: Fix irq_domain_alloc_irqs_recursive() error handling
irq/Documentation: Correct result of echnoing 5 to smp_affinity
MAINTAINERS: Remove Jiang Liu from irq domains
genirq/msi: Fix broken debug output
genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectors
genirq/msi: Make use of affinity aware allocations
genirq: Use affinity hint in irqdesc allocation
genirq: Add affinity hint to irq allocation
genirq: Introduce IRQD_AFFINITY_MANAGED flag
genirq/msi: Remove unused MSI_FLAG_IDENTITY_MAP
irqchip/s3c24xx: Fixup IO accessors for big endian
irqchip/exynos-combiner: Fix usage of __raw IO
irqdomain: Fix disposal of mappings for interrupt hierarchies
irqchip/aspeed-vic: Add irq controller for Aspeed
doc/devicetree: Add Aspeed VIC bindings
x86/PCI/VMD: Use untracked irq handler
genirq: Add untracked irq handler
irqchip/mips-gic: Populate irq_domain names
irqchip/gicv3-its: Implement two-level(indirect) device table support
...
Pull timer updates from Thomas Gleixner:
"This update provides the following changes:
- The rework of the timer wheel which addresses the shortcomings of
the current wheel (cascading, slow search for next expiring timer,
etc). That's the first major change of the wheel in almost 20
years since Finn implemted it.
- A large overhaul of the clocksource drivers init functions to
consolidate the Device Tree initialization
- Some more Y2038 updates
- A capability fix for timerfd
- Yet another clock chip driver
- The usual pile of updates, comment improvements all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (130 commits)
tick/nohz: Optimize nohz idle enter
clockevents: Make clockevents_subsys static
clocksource/drivers/time-armada-370-xp: Fix return value check
timers: Implement optimization for same expiry time in mod_timer()
timers: Split out index calculation
timers: Only wake softirq if necessary
timers: Forward the wheel clock whenever possible
timers/nohz: Remove pointless tick_nohz_kick_tick() function
timers: Optimize collect_expired_timers() for NOHZ
timers: Move __run_timers() function
timers: Remove set_timer_slack() leftovers
timers: Switch to a non-cascading wheel
timers: Reduce the CPU index space to 256k
timers: Give a few structs and members proper names
hlist: Add hlist_is_singular_node() helper
signals: Use hrtimer for sigtimedwait()
timers: Remove the deprecated mod_timer_pinned() API
timers, net/ipv4/inet: Initialize connection request timers as pinned
timers, drivers/tty/mips_ejtag: Initialize the poll timer as pinned
timers, drivers/tty/metag_da: Initialize the poll timer as pinned
...
Pull x86 fix from Ingo Molnar:
"Leftover fix from the v4.7 cycle: adds a reboot quirk"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/reboot: Add Dell Optiplex 7450 AIO reboot quirk
Pull x86 timer updates from Ingo Molnar:
"The main change in this tree is the reworking, fixing and extension of
the TSC frequency enumeration code (by Len Brown)"
* 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tsc: Remove the unused check_tsc_disabled()
x86/tsc: Enumerate BXT tsc_khz via CPUID
x86/tsc: Enumerate SKL cpu_khz and tsc_khz via CPUID
x86/tsc_msr: Remove irqoff around MSR-based TSC enumeration
x86/tsc_msr: Add Airmont reference clock values
x86/tsc_msr: Correct Silvermont reference clock values
x86/tsc_msr: Update comments, expand definitions
x86/tsc_msr: Remove debugging messages
x86/tsc_msr: Identify Intel-specific code
Revert "x86/tsc: Add missing Cherrytrail frequency to the table"
Pull x86 platform updates from Ingo Molnar:
"The main changes in this cycle were:
- Intel-SoC enhancements (Andy Shevchenko)
- Intel CPU symbolic model definition rework (Dave Hansen)
- ... other misc changes"
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
x86/sfi: Enable enumeration of SD devices
x86/pci: Use MRFLD abbreviation for Merrifield
x86/platform/intel-mid: Make vertical indentation consistent
x86/platform/intel-mid: Mark regulators explicitly defined
x86/platform/intel-mid: Rename mrfl.c to mrfld.c
x86/platform/intel-mid: Enable spidev on Intel Edison boards
x86/platform/intel-mid: Extend PWRMU to support Penwell
x86/pci, x86/platform/intel_mid_pci: Remove duplicate power off code
x86/platform/intel-mid: Add pinctrl for Intel Merrifield
x86/platform/intel-mid: Enable GPIO expanders on Edison
x86/platform/intel-mid: Add Power Management Unit driver
x86/platform/atom/punit: Enable support for Merrifield
x86/platform/intel_mid_pci: Rework IRQ0 workaround
x86, thermal: Clean up and fix CPU model detection for intel_soc_dts_thermal
x86, mmc: Use Intel family name macros for mmc driver
x86/intel_telemetry: Use Intel family name macros for telemetry driver
x86/acpi/lss: Use Intel family name macros for the acpi_lpss driver
x86/cpufreq: Use Intel family name macros for the intel_pstate cpufreq driver
x86/platform: Use new Intel model number macros
x86/intel_idle: Use Intel family macros for intel_idle
...
Pull x86 fpu updates from Ingo Molnar:
"The main x86 FPU changes in this cycle were:
- a large series of cleanups, fixes and enhancements to re-enable the
XSAVES instruction on Intel CPUs - which is the most advanced
instruction to do FPU context switches (Yu-cheng Yu, Fenghua Yu)
- Add FPU tracepoints for the FPU state machine (Dave Hansen)"
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu: Do not BUG_ON() in early FPU code
x86/fpu/xstate: Re-enable XSAVES
x86/fpu/xstate: Fix fpstate_init() for XRSTORS
x86/fpu/xstate: Return NULL for disabled xstate component address
x86/fpu/xstate: Fix __fpu_restore_sig() for XSAVES
x86/fpu/xstate: Fix xstate_offsets, xstate_sizes for non-extended xstates
x86/fpu/xstate: Fix XSTATE component offset print out
x86/fpu/xstate: Fix PTRACE frames for XSAVES
x86/fpu/xstate: Fix supervisor xstate component offset
x86/fpu/xstate: Align xstate components according to CPUID
x86/fpu/xstate: Copy xstate registers directly to the signal frame when compacted format is in use
x86/fpu/xstate: Keep init_fpstate.xsave.header.xfeatures as zero for init optimization
x86/fpu/xstate: Rename 'xstate_size' to 'fpu_kernel_xstate_size', to distinguish it from 'fpu_user_xstate_size'
x86/fpu/xstate: Define and use 'fpu_user_xstate_size'
x86/fpu: Add tracepoints to dump FPU state at key points
Pull x86 stackdump update from Ingo Molnar:
"A number of stackdump enhancements"
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/dumpstack: Add show_stack_regs() and use it
printk: Make the printk*once() variants return a value
x86/dumpstack: Honor supplied @regs arg
Pull x86 cleanups from Ingo Molnar:
"Three small cleanups"
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
lguest: Read offset of device_cap later
lguest: Read length of device_cap later
x86: Do away with ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB
Pull x86 build updates from Ingo Molnar:
"A build system fix and a cleanup"
* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
kbuild: Remove stale asm-generic wrappers
kbuild, x86: Track generated headers with generated-y
Pull x86 boot updates from Ingo Molnar:
"The main changes:
- add initial commits to randomize kernel memory section virtual
addresses, enabled via a new kernel option: RANDOMIZE_MEMORY
(Thomas Garnier, Kees Cook, Baoquan He, Yinghai Lu)
- enhance KASLR (RANDOMIZE_BASE) physical memory randomization (Kees
Cook)
- EBDA/BIOS region boot quirk cleanups (Andy Lutomirski, Ingo Molnar)
- misc cleanups/fixes"
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Simplify EBDA-vs-BIOS reservation logic
x86/boot: Clarify what x86_legacy_features.reserve_bios_regions does
x86/boot: Reorganize and clean up the BIOS area reservation code
x86/mm: Do not reference phys addr beyond kernel
x86/mm: Add memory hotplug support for KASLR memory randomization
x86/mm: Enable KASLR for vmalloc memory regions
x86/mm: Enable KASLR for physical mapping memory regions
x86/mm: Implement ASLR for kernel memory regions
x86/mm: Separate variable for trampoline PGD
x86/mm: Add PUD VA support for physical mapping
x86/mm: Update physical mapping variable names
x86/mm: Refactor KASLR entropy functions
x86/KASLR: Fix boot crash with certain memory configurations
x86/boot/64: Add forgotten end of function marker
x86/KASLR: Allow randomization below the load address
x86/KASLR: Extend kernel image physical address randomization to addresses larger than 4G
x86/KASLR: Randomize virtual address separately
x86/KASLR: Clarify identity map interface
x86/boot: Refuse to build with data relocations
x86/KASLR, x86/power: Remove x86 hibernation restrictions
Pull x86 mm updates from Ingo Molnar:
"Various x86 low level modifications:
- preparatory work to support virtually mapped kernel stacks (Andy
Lutomirski)
- support for 64-bit __get_user() on 32-bit kernels (Benjamin
LaHaise)
- (involved) workaround for Knights Landing CPU erratum (Dave Hansen)
- MPX enhancements (Dave Hansen)
- mremap() extension to allow remapping of the special VDSO vma, for
purposes of user level context save/restore (Dmitry Safonov)
- hweight and entry code cleanups (Borislav Petkov)
- bitops code generation optimizations and cleanups with modern GCC
(H. Peter Anvin)
- syscall entry code optimizations (Paolo Bonzini)"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
x86/mm/cpa: Add missing comment in populate_pdg()
x86/mm/cpa: Fix populate_pgd(): Stop trying to deallocate failed PUDs
x86/syscalls: Add compat_sys_preadv64v2/compat_sys_pwritev64v2
x86/smp: Remove unnecessary initialization of thread_info::cpu
x86/smp: Remove stack_smp_processor_id()
x86/uaccess: Move thread_info::addr_limit to thread_struct
x86/dumpstack: Rename thread_struct::sig_on_uaccess_error to sig_on_uaccess_err
x86/uaccess: Move thread_info::uaccess_err and thread_info::sig_on_uaccess_err to thread_struct
x86/dumpstack: When OOPSing, rewind the stack before do_exit()
x86/mm/64: In vmalloc_fault(), use CR3 instead of current->active_mm
x86/dumpstack/64: Handle faults when printing the "Stack: " part of an OOPS
x86/dumpstack: Try harder to get a call trace on stack overflow
x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables()
x86/mm/cpa: In populate_pgd(), don't set the PGD entry until it's populated
x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()
x86/mm: Use pte_none() to test for empty PTE
x86/mm: Disallow running with 32-bit PTEs to work around erratum
x86/mm: Ignore A/D bits in pte/pmd/pud_none()
x86/mm: Move swap offset/type up in PTE to work around erratum
x86/entry: Inline enter_from_user_mode()
...
Pull x86/apic updates from Ingo Molnar:
"Misc cleanups and a small fix"
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Remove the unused struct apic::apic_id_mask field
x86/apic: Fix misspelled APIC
x86/ioapic: Simplify ioapic_setup_resources()
Pull NOHZ updates from Ingo Molnar:
- fix system/idle cputime leaked on cputime accounting (all nohz
configs) (Rik van Riel)
- remove the messy, ad-hoc irqtime account on nohz-full and make it
compatible with CONFIG_IRQ_TIME_ACCOUNTING=y instead (Rik van Riel)
- cleanups (Frederic Weisbecker)
- remove unecessary irq disablement in the irqtime code (Rik van Riel)
* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/cputime: Drop local_irq_save/restore from irqtime_account_irq()
sched/cputime: Reorganize vtime native irqtime accounting headers
sched/cputime: Clean up the old vtime gen irqtime accounting completely
sched/cputime: Replace VTIME_GEN irq time code with IRQ_TIME_ACCOUNTING code
sched/cputime: Count actually elapsed irq & softirq time
Pull scheduler updates from Ingo Molnar:
- introduce and use task_rcu_dereference()/try_get_task_struct() to fix
and generalize task_struct handling (Oleg Nesterov)
- do various per entity load tracking (PELT) fixes and optimizations
(Peter Zijlstra)
- cputime virt-steal time accounting enhancements/fixes (Wanpeng Li)
- introduce consolidated cputime output file cpuacct.usage_all and
related refactorings (Zhao Lei)
- ... plus misc fixes and enhancements
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Panic on scheduling while atomic bugs if kernel.panic_on_warn is set
sched/cpuacct: Introduce cpuacct.usage_all to show all CPU stats together
sched/cpuacct: Use loop to consolidate code in cpuacct_stats_show()
sched/cpuacct: Merge cpuacct_usage_index and cpuacct_stat_index enums
sched/fair: Rework throttle_count sync
sched/core: Fix sched_getaffinity() return value kerneldoc comment
sched/fair: Reorder cgroup creation code
sched/fair: Apply more PELT fixes
sched/fair: Fix PELT integrity for new tasks
sched/cgroup: Fix cpu_cgroup_fork() handling
sched/fair: Fix PELT integrity for new groups
sched/fair: Fix and optimize the fork() path
sched/cputime: Add steal time support to full dynticks CPU time accounting
sched/cputime: Fix prev steal time accouting during CPU hotplug
KVM: Fix steal clock warp during guest CPU hotplug
sched/debug: Always show 'nr_migrations'
sched/fair: Use task_rcu_dereference()
sched/api: Introduce task_rcu_dereference() and try_get_task_struct()
sched/idle: Optimize the generic idle loop
sched/fair: Fix the wrong throttled clock time for cfs_rq_clock_task()
Pull perf updates from Ingo Molnar:
"With over 300 commits it's been a busy cycle - with most of the work
concentrated on the tooling side (as it should).
The main kernel side enhancements were:
- Add per event callchain limit: Recently we introduced a sysctl to
tune the max-stack for all events for which callchains were
requested:
$ sysctl kernel.perf_event_max_stack
kernel.perf_event_max_stack = 127
Now this patch introduces a way to configure this per event, i.e.
this becomes possible:
$ perf record -e sched:*/max-stack=2/ -e block:*/max-stack=10/ -a
allowing finer tuning of how much buffer space callchains use.
This uses an u16 from the reserved space at the end, leaving
another u16 for future use.
There has been interest in even finer tuning, namely to control the
max stack for kernel and userspace callchains separately. Further
discussion is needed, we may for instance use the remaining u16 for
that and when it is present, assume that the sample_max_stack
introduced in this patch applies for the kernel, and the u16 left
is used for limiting the userspace callchain (Arnaldo Carvalho de
Melo)
- Optimize AUX event (hardware assisted side-band event) delivery
(Kan Liang)
- Rework Intel family name macro usage (this is partially x86 arch
work) (Dave Hansen)
- Refine and fix Intel LBR support (David Carrillo-Cisneros)
- Add support for Intel 'TopDown' events (Andi Kleen)
- Intel uncore PMU driver fixes and enhancements (Kan Liang)
- ... other misc changes.
Here's an incomplete list of the tooling enhancements (but there's
much more, see the shortlog and the git log for details):
- Support cross unwinding, i.e. collecting '--call-graph dwarf'
perf.data files in one machine and then doing analysis in another
machine of a different hardware architecture. This enables, for
instance, to do:
$ perf record -a --call-graph dwarf
on a x86-32 or aarch64 system and then do 'perf report' on it on a
x86_64 workstation (He Kuang)
- Allow reading from a backward ring buffer (one setup via
sys_perf_event_open() with perf_event_attr.write_backward = 1)
(Wang Nan)
- Finish merging initial SDT (Statically Defined Traces) support, see
cset comments for details about how it all works (Masami Hiramatsu)
- Support attaching eBPF programs to tracepoints (Wang Nan)
- Add demangling of symbols in programs written in the Rust language
(David Tolnay)
- Add support for tracepoints in the python binding, including an
example, that sets up and parses sched:sched_switch events,
tools/perf/python/tracepoint.py (Jiri Olsa)
- Introduce --stdio-color to set up the color output mode selection
in 'annotate' and 'report', allowing emit color escape sequences
when redirecting the output of these tools (Arnaldo Carvalho de
Melo)
- Add 'callindent' option to 'perf script -F', to indent the Intel PT
call stack, making this output more ftrace-like (Adrian Hunter,
Andi Kleen)
- Allow dumping the object files generated by llvm when processing
eBPF scriptlet events (Wang Nan)
- Add stackcollapse.py script to help generating flame graphs (Paolo
Bonzini)
- Add --ldlat option to 'perf mem' to specify load latency for loads
event (e.g. cpu/mem-loads/ ) (Jiri Olsa)
- Tooling support for Intel TopDown counters, recently added to the
kernel (Andi Kleen)"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (303 commits)
perf tests: Add is_printable_array test
perf tools: Make is_printable_array global
perf script python: Fix string vs byte array resolving
perf probe: Warn unmatched function filter correctly
perf cpu_map: Add more helpers
perf stat: Balance opening and reading events
tools: Copy linux/{hash,poison}.h and check for drift
perf tools: Remove include/linux/list.h from perf's MANIFEST
tools: Copy the bitops files accessed from the kernel and check for drift
Remove: kernel unistd*h files from perf's MANIFEST, not used
perf tools: Remove tools/perf/util/include/linux/const.h
perf tools: Remove tools/perf/util/include/asm/byteorder.h
perf tools: Add missing linux/compiler.h include to perf-sys.h
perf jit: Remove some no-op error handling
perf jit: Add missing curly braces
objtool: Initialize variable to silence old compiler
objtool: Add -I$(srctree)/tools/arch/$(ARCH)/include/uapi
perf record: Add --tail-synthesize option
perf session: Don't warn about out of order event if write_backward is used
perf tools: Enable overwrite settings
...
Pull RAS updates from Ingo Molnar:
"The biggest change in this cycle was an enhancement by Yazen Ghannam
to reduce the number of MCE error injection related IPIs.
The rest are smaller fixes"
* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Fix mce_rdmsrl() warning message
x86/RAS/AMD: Reduce the number of IPIs when prepping error injection
x86/mce/AMD: Increase size of the bank_map type
x86/mce: Do not use bank 1 for APEI generated error logs
Pull locking updates from Ingo Molnar:
"The locking tree was busier in this cycle than the usual pattern - a
couple of major projects happened to coincide.
The main changes are:
- implement the atomic_fetch_{add,sub,and,or,xor}() API natively
across all SMP architectures (Peter Zijlstra)
- add atomic_fetch_{inc/dec}() as well, using the generic primitives
(Davidlohr Bueso)
- optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
Waiman Long)
- optimize smp_cond_load_acquire() on arm64 and implement LSE based
atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
on arm64 (Will Deacon)
- introduce smp_acquire__after_ctrl_dep() and fix various barrier
mis-uses and bugs (Peter Zijlstra)
- after discovering ancient spin_unlock_wait() barrier bugs in its
implementation and usage, strengthen its semantics and update/fix
usage sites (Peter Zijlstra)
- optimize mutex_trylock() fastpath (Peter Zijlstra)
- ... misc fixes and cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
locking/static_keys: Fix non static symbol Sparse warning
locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
locking/atomic, arch/tile: Fix tilepro build
locking/atomic, arch/m68k: Remove comment
locking/atomic, arch/arc: Fix build
locking/Documentation: Clarify limited control-dependency scope
locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
locking/atomic, arch/mips: Convert to _relaxed atomics
locking/atomic, arch/alpha: Convert to _relaxed atomics
locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
locking/atomic: Fix atomic64_relaxed() bits
locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
...
Pull EFI updates from Ingo Molnar:
"The biggest change in this cycle were SGI/UV related changes that
clean up and fix UV boot quirks and problems.
There's also various smaller cleanups and refinements"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Reorganize the GUID table to make it easier to read
x86/efi: Remove the unused efi_get_time() function
x86/efi: Update efi_thunk() to use the the arch_efi_call_virt*() macros
x86/uv: Update uv_bios_call() to use efi_call_virt_pointer()
efi: Convert efi_call_virt() to efi_call_virt_pointer()
x86/efi: Remove unused variable 'efi'
efi: Document #define FOO_PROTOCOL_GUID layout
efibc: Report more information in the error messages
Pull RCU updates from Ingo Molnar:
"The main changes in this cycle were:
- documentation updates
- miscellaneous fixes
- minor reorganization of code
- torture-test updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
rcu: Correctly handle sparse possible cpus
rcu: sysctl: Panic on RCU Stall
rcu: Fix a typo in a comment
rcu: Make call_rcu_tasks() tolerate first call with irqs disabled
rcu: Disable TASKS_RCU for usermode Linux
rcu: No ordering for rcu_assign_pointer() of NULL
rcutorture: Fix error return code in rcu_perf_init()
torture: Inflict default jitter
rcuperf: Don't treat gp_exp mis-setting as a WARN
rcutorture: Drop "-soundhw pcspkr" from x86 boot arguments
rcutorture: Don't specify the cpu type of QEMU on PPC
rcutorture: Make -soundhw a x86 specific option
rcutorture: Use vmlinux as the fallback kernel image
rcutorture/doc: Create initrd using dracut
torture: Stop onoff task if there is only one cpu
torture: Add starvation events to error summary
torture: Break online and offline functions out of torture_onoff()
torture: Forgive lengthy trace dumps and preemption
torture: Remove CONFIG_RCU_TORTURE_TEST_RUNNABLE, simplify code
torture: Simplify code, eliminate RCU_PERF_TEST_RUNNABLE
...
New drivers for FTS BMC "Teutates", TI INA3221, and Sensirion SHT3x.
Added support for Microchip MCP9808 and TI TMP461.
Cleanup and minor fixes in various drivers.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=O4g9
-----END PGP SIGNATURE-----
Merge tag 'hwmon-for-linus-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon updates from Guenter Roeck:
- New drivers for FTS BMC "Teutates", TI INA3221, and Sensirion SHT3x.
- Added support for Microchip MCP9808 and TI TMP461.
- Cleanup and minor fixes in various drivers.
* tag 'hwmon-for-linus-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (37 commits)
Documentation: dtb: xgene: Add hwmon dts binding documentation
hwmon: (ftsteutates) Remove unused including <linux/version.h>
hwmon: (adt7411) set bit 3 in CFG1 register
hwmon: Add driver for FTS BMC chip "Teutates"
hwmon: (sht3x) add humidity heater element control
hwmon: (jc42) Add support for generic JC-42.4 devicetree binding
dt/bindings: Add bindings for JC-42.4 compatible temperature sensors
hwmon: (tmp102) Convert to use regmap, and drop local cache
hwmon: (tmp102) Rework chip configuration
hwmon: (tmp102) Improve handling of initial read delay
hwmon: (lm90) Drop unnecessary else statements
hwmon: (lm90) Use bool for valid flag
hwmon: (lm90) Read limit registers only once
hwmon: (lm90) Simplify read functions
hwmon: (lm90) Use devm_hwmon_device_register_with_groups
hwmon: (lm90) Use devm_add_action for cleanup
hwmon: (lm75) Convert to use regmap
hwmon: (lm75) Add update_interval attribute
hwmon: (lm75) Drop lm75_read_value and lm75_write_value
hwmon: (lm75) Handle cleanup with devm_add_action
...
* Drop us of SH Drivers on Renesas ARM Based SoCs
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=FUiM
-----END PGP SIGNATURE-----
Merge tag 'renesas-sh-drivers-for-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas
Pull SH drivers updates from Simon Horman:
"Drop use of SH Drivers on Renesas ARM Based SoCs.
I expect this to be my last pull request for these drivers as it
removes usage of them from Renesas ARM Based SoCs and my
co-maintenance of them.
The drivers are still used by some SH SoCs and listed under SUPERH in
the MAINTAINERS file"
* tag 'renesas-sh-drivers-for-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
MAINTAINERS: Drop drivers/sh/ for Renesas ARM
drivers: sh: Stop using the legacy clock domain on ARM
Here's the big USB driver update for 4.8-rc1. Lots of the normal stuff
in here, musb, gadget, xhci, and other updates and fixes. All of the
details are in the shortlog.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iFYEABECABYFAleVPioPHGdyZWdAa3JvYWguY29tAAoJEDFH1A3bLfspB5AAnj7a
VJ2t2kcWzFUNQ6dyJrJCGGRAAKDZmb5CnOGeqJmdVpDzN1CGLYjfiw==
=47iA
-----END PGP SIGNATURE-----
Merge tag 'usb-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB updates from Greg KH:
"Here's the big USB driver update for 4.8-rc1. Lots of the normal
stuff in here, musb, gadget, xhci, and other updates and fixes. All
of the details are in the shortlog.
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (169 commits)
cdc-acm: beautify probe()
cdc-wdm: use the common CDC parser
cdc-acm: cleanup error handling
cdc-acm: use the common parser
usbnet: move the CDC parser into USB core
usb: musb: sunxi: Simplify dr_mode handling
usb: musb: sunxi: make unexported symbols static
usb: musb: cppi41: add dma channel tracepoints
usb: musb: cppi41: move struct cppi41_dma_channel to header
usb: musb: cleanup cppi_dma header
usb: musb: gadget: add usb-request tracepoints
usb: musb: host: add urb tracepoints
usb: musb: add tracepoints to dump interrupt events
usb: musb: add tracepoints for register access
usb: musb: dsps: use musb register read/write wrappers instead
usb: musb: switch dev_dbg to tracepoints
usb: musb: add tracepoints support for debugging
usb: quirks: Add no-lpm quirk for Elan
phy: rcar-gen3-usb2: fix mutex_lock calling in interrupt
phy: rockhip-usb: use devm_add_action_or_reset()
...
Here is the big tty and serial driver update for 4.8-rc1.
Lots of good cleanups from Jiri on a number of vt and other tty related
things, and the normal driver updates. Full details are in the
shortlog.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iFYEABECABYFAleVPbQPHGdyZWdAa3JvYWguY29tAAoJEDFH1A3bLfspWXgAn046
QCMeFya4J1zjYjcGXJzNfGMUAKCHxha8Xe65cc0LDz8mNB0MgzjHEg==
=ED8v
-----END PGP SIGNATURE-----
Merge tag 'tty-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here is the big tty and serial driver update for 4.8-rc1.
Lots of good cleanups from Jiri on a number of vt and other tty
related things, and the normal driver updates. Full details are in
the shortlog.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (90 commits)
tty/serial: atmel: enforce tasklet init and termination sequences
serial: sh-sci: Stop transfers in sci_shutdown()
serial: 8250_ingenic: drop #if conditional surrounding earlycon code
serial: 8250_mtk: drop !defined(MODULE) conditional
serial: 8250_uniphier: drop !defined(MODULE) conditional
earlycon: mark earlycon code as __used iif the caller is built-in
tty/serial/8250: use mctrl_gpio helpers
serial: mctrl_gpio: enable API usage only for initialized mctrl_gpios struct
serial: mctrl_gpio: add modem control read routine
tty/serial/8250: make UART_MCR register access consistent
serial: 8250_mid: Read RX buffer on RX DMA timeout for DNV
serial: 8250_dma: Export serial8250_rx_dma_flush()
dmaengine: hsu: Export hsu_dma_get_status()
tty: serial: 8250: add CON_CONSDEV to flags
tty: serial: samsung: add byte-order aware bit functions
tty: serial: samsung: fixup accessors for endian
serial: sirf: make fifo functions static
serial: mps2-uart: make driver explicitly non-modular
serial: mvebu-uart: free the IRQ in ->shutdown()
serial/bcm63xx_uart: use correct alias naming
...
Here is the big Staging and IIO driver update for 4.8-rc1.
We ended up adding more code than removing, again, but it's not all that
bad. Lots of cleanups all over the staging tree, and new IIO drivers,
full details in the shortlog.
All of these have been in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iFYEABECABYFAleVPQQPHGdyZWdAa3JvYWguY29tAAoJEDFH1A3bLfsplRgAniG6
jfPnvlHhl70T5HsGJzrc7VS9AKCBQ5x0gzTNxo2nnGfPmR8CVEH7Bg==
=0/6X
-----END PGP SIGNATURE-----
Merge tag 'staging-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO driver updates from Greg KH:
"Here is the big Staging and IIO driver update for 4.8-rc1.
We ended up adding more code than removing, again, but it's not all
that bad. Lots of cleanups all over the staging tree, and new IIO
drivers, full details in the shortlog.
All of these have been in linux-next for a while with no reported
issues"
* tag 'staging-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (417 commits)
drivers:iio:accel:mma8452: removed unwanted return statements
drivers:iio:accel:mma8452: added cleanup provision in case of failure.
iio: Add iio.git tree to MAINTAINERS
iio:st_pressure: clean useless static channel initializers
iio:st_pressure:lps22hb: temperature support
iio:st_pressure:lps22hb: open drain support
iio:st_pressure: temperature triggered buffering
iio:st_pressure: document sampling gains
iio:st_pressure: align storagebits on power of 2
iio:st_sensors: align on storagebits boundaries
staging:iio:lis3l02dq drop separate driver
iio: accel: st_accel: Add lis3l02dq support
iio: adc: add missing of_node references to iio_dev
iio: adc: ti-ads1015: add indio_dev->dev.of_node reference
iio: potentiometer: Fix typo in Kconfig
iio: potentiometer: mcp4531: Add device tree binding
iio: potentiometer: mcp4531: Add device tree binding documentation
iio: potentiometer: mcp4531: Add support for MCP454x, MCP456x, MCP464x and MCP466x
iio:imu:mpu6050: icm20608 initial support
iio: adc: max1363: Add device tree binding
...
Here is the big char/misc driver update for 4.8-rc1.
Not a lot of stuff, but it's all over the place, full details are in the
shortlog below. All of these have been in linux-next with no reported
issues for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iFYEABECABYFAleVPBsPHGdyZWdAa3JvYWguY29tAAoJEDFH1A3bLfspEQgAoJOX
nSWKA7j4JMGy1v+uNIqsgUmUAJsFyS388N+Faa2K4uyp7CYQ6jaAZw==
=0Ofd
-----END PGP SIGNATURE-----
Merge tag 'char-misc-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the big char/misc driver update for 4.8-rc1.
Not a lot of stuff, but it's all over the place, full details are in
the shortlog. All of these have been in linux-next with no reported
issues for a while"
* tag 'char-misc-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (49 commits)
lkdtm: silence warnings about function declarations
lkdtm: hide unused functions
intel_th: pci: Add Kaby Lake PCH-H support
intel_th: Fix a deadlock in modprobing
dsp56k: prevent a harmless underflow
chardev: add missing line break in pr_warn
lkdtm: use struct arrays instead of enums
lkdtm: move jprobe entry points to start of source
lkdtm: reorganize module paramaters
lkdtm: rename globals for clarity
lkdtm: rename "count" to "crash_count"
lkdtm: remove intentional off-by-one array access
lkdtm: split remaining logic bug tests to separate file
lkdtm: split heap corruption tests to separate file
lkdtm: split memory permissions tests to separate file
lkdtm: split usercopy tests to separate file
lkdtm: drop "alloc_size" parameter
lkdtm: add usercopy test for blocking kernel text
extcon: adc-jack: add suspend/resume support
extcon: add missing of_node_put after calling of_parse_phandle
...
of nasty outcomes when inodes are transitioned from the unlinked state
to the free state. Small file systems are particularly vulnerable to these
problems, and it can manifest as mainly hangs, but also file system
corruption. The patches have been tested for literally many weeks, with a
very gruelling test, so I have a high level of confidence.
- Andreas Gruenbacher wrote a series of 5 patches for various lockups
during the transition of inodes from unlinked to free. The main patch
is titled "Fix gfs2_lookup_by_inum lock inversion" and the other 4 are
support and cleanup patches related to that.
- Ben Marzinski contributed 2 patches with regard to a recreatable
problem when gfs2 tries to write a page to a file that is being
truncated, resulting in a BUG() in gfs2_remove_from_journal.
Note that Ben had to export vfs function __block_write_full_page to get
this to work properly. It's been posted a long time and he talked to
various VFS people about it, and nobody seemed to mind.
- I contributed 3 patches. (1) The first one fixes a memory corruptor:
a race in which one process can overwrite the gl_object pointer set by
another process, causing kernel panic and other symptoms. (2) The second
patch fixes another race that resulted in a false-positive BUG_ON. This
occurred when resource group reservations were freed by one process
while another process was trying to grab a new reservation in the same
resource group. (3) The third patch fixes a problem with doing journal
replay when the journals are not all the same size.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXklXIAAoJENeLYdPf93o7AbIIAImLEixK+4CaItEArAKG9TXv
WbO+eDJfo6AOtAteB6+MdX2UxXAHJsCY6RmiEIAi5LzlVFiiCgRo4z/QgDARAw3c
2RxlndElaESh82S27sLiFbgZeY7GZv04C0t6AzMkc830BLXiKMs6bXfeq1fzW8Sf
AgAneACVsX0faRWo/XDuQcK81dwZ+qdOnR2+FvtOSFl1KgV0BrtnsW7IHv+5MIot
SREDN7VvSQwQrLgwMlC0PvhwK3KCVvuO9ZziLEPpYJONESJfEmuCpG265+tUJNTw
dIcW3p/vvgow8fb56fSnAxaeplPLlF9qJCq1M9fWZrKVbHg2uyCZMx4P52Fnmz4=
=uUVs
-----END PGP SIGNATURE-----
Merge tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 updates from Bob Peterson:
"We've got ten patches this time, half of which are related to a
plethora of nasty outcomes when inodes are transitioned from the
unlinked state to the free state. Small file systems are particularly
vulnerable to these problems, and it can manifest as mainly hangs, but
also file system corruption. The patches have been tested for
literally many weeks, with a very gruelling test, so I have a high
level of confidence.
- Andreas Gruenbacher wrote a series of five patches for various
lockups during the transition of inodes from unlinked to free.
The main patch is titled "Fix gfs2_lookup_by_inum lock inversion"
and the other four are support and cleanup patches related to that.
- Ben Marzinski contributed two patches with regard to a recreatable
problem when gfs2 tries to write a page to a file that is being
truncated, resulting in a BUG() in gfs2_remove_from_journal.
Note that Ben had to export vfs function __block_write_full_page to
get this to work properly. It's been posted a long time and he
talked to various VFS people about it, and nobody seemed to mind.
- I contributed 3 patches:
o The first one fixes a memory corruptor: a race in which one
process can overwrite the gl_object pointer set by another
process, causing kernel panic and other symptoms.
o The second patch fixes another race that resulted in a
false-positive BUG_ON. This occurred when resource group
reservations were freed by one process while another process
was trying to grab a new reservation in the same resource
group.
o The third patch fixes a problem with doing journal replay when
the journals are not all the same size"
* tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
GFS2: Fix gfs2_replay_incr_blk for multiple journal sizes
GFS2: Check rs_free with rd_rsspin protection
gfs2: writeout truncated pages
fs: export __block_write_full_page
gfs2: Lock holder cleanup
gfs2: Large-filesystem fix for 32-bit systems
gfs2: Get rid of gfs2_ilookup
gfs2: Fix gfs2_lookup_by_inum lock inversion
gfs2: Initialize iopen glock holder for new inodes
GFS2: don't set rgrp gl_object until it's inserted into rgrp tree
that caused misdirected requests, tagged for stable.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iQEcBAABCAAGBQJXk4kSAAoJEEp/3jgCEfOLvpsIAKJTs1ELIQ5RmfvwdvqyqI0N
DoSA6rBYIwQvjqBjevJw72w5HKR7hhJoxaEjXEFrw9zbRmXMNnlk5xZpgD8vy5E3
1iCA8LtscFp4ld4ZNWIus45mUpf6/a5ugPd9Mr3V5C4J05LWqZeXufpAHNHyFbII
++hTu6J/RAg8DddEUhBcDl7c65tQpc8ai0h8ll0pLRYNFLPeCoYO3yTitEYax4fR
i6erB3+7pNWnZIsPnUTrXS4B2NG5kPmflVkD7UH9i14PwdQ4QO85LSXD1o8xYrpa
Occ9EvgFuT8zTJHckCEcT2Y0dINz2uHiE05DUea3Udz82keV9zKeZhZUDwJ95RE=
=P1qk
-----END PGP SIGNATURE-----
Merge tag 'ceph-for-4.7-rc8' of git://github.com/ceph/ceph-client
Pull ceph fix from Ilya Dryomov:
"A fix for a long-standing bug in the incremental osdmap handling code
that caused misdirected requests, tagged for stable"
The tag is signed with a brand new key - Sage is on vacation and I
didn't anticipate this"
* tag 'ceph-for-4.7-rc8' of git://github.com/ceph/ceph-client:
libceph: apply new_state before new_up_client on incrementals
In commit:
21cbc2822aa1 ("x86/mm/cpa: Unbreak populate_pgd(): stop trying to deallocate failed PUDs")
I intended to add this comment, but I failed at using git.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/242baf8612394f4e31216f96d13c4d2e9b90d1b7.1469293159.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Valdis Kletnieks bisected a boot failure back to this recent commit:
360cb4d155 ("x86/mm/cpa: In populate_pgd(), don't set the PGD entry until it's populated")
I broke the case where a PUD table got allocated -- populate_pud()
would wander off a pgd_none entry and get lost. I'm not sure how
this survived my testing.
Fix the original issue in a much simpler way. The problem
was that, if we allocated a PUD table, failed to populate it, and
freed it, another CPU could potentially keep using the PGD entry we
installed (either by copying it via vmalloc_fault or by speculatively
caching it). There's a straightforward fix: simply leave the
top-level entry in place if this happens. This can't waste any
significant amount of memory -- there are at most 256 entries like
this systemwide and, as a practical matter, if we hit this failure
path repeatedly, we're likely to reuse the same page anyway.
For context, this is a reversion with this hunk added in:
if (ret < 0) {
+ /*
+ * Leave the PUD page in place in case some other CPU or thread
+ * already found it, but remove any useless entries we just
+ * added to it.
+ */
- unmap_pgd_range(cpa->pgd, addr,
+ unmap_pud_range(pgd_entry, addr,
addr + (cpa->numpages << PAGE_SHIFT));
return ret;
}
This effectively open-codes what the now-deleted unmap_pgd_range()
function used to do except that unmap_pgd_range() used to try to
free the page as well.
Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Mike Krinkin <krinkin.m.u@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Link: http://lkml.kernel.org/r/21cbc2822aa18aa812c0215f4231dbf5f65afa7f.1469249789.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Garnier