Flush and discard requests would previously mess up the accounting.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
This patch creates the character device as long as a device's admin queues
are usable so a user has an opprotunity to perform administration tasks.
A device may be in a state that does not allow IO and setting the queue
count feature in such a state returns an error. Previously the driver
would bail and the controller would be unusable.
Signed-off-by: Keith Busch <keith.busch@intel.com>
The 'Number of Namespaces' read from the device was being treated as
signed, which would cause us to not scan any namespaces for a device
with more than 2 billion namespaces. That led to noticing that the
namespace ID was also being treated as signed, which could lead to the
result from NVME_IOCTL_ID being treated as an error code.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
To build user programs that call the NVMe ioctls, we need to have a
user header file. Catch up to the new way of doing that by splitting
the header file into kernel and uapi portions.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Since we have the queue locked, it makes sense to check if there are
any completion queue entries on the queue before we release the lock.
If there are, it may save an interrupt and reduce latency for the I/Os
that happened to complete. This happens fairly often for some workloads.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
I was originally intending to log the fact that the kthread had done
some work since it might help us find interrupt handling problems, but
that hasn't been done yet, and spamming the logs with this message is
just rude.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
The interrupt handler currently reports whether it found any new
completion queue entries. If the completion queue is primarily being
processed by a method other than the interrupt handler, it may return
IRQ_NONE so often that Linux thinks that the interrupt is being falsely
triggered.
To solve this problem, report whether any completion queue entries have
been seen since the last interrupt was received for this queue.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Add io stats accounting for bio requests so nvme block devices show
useful disk stats.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
The current code copies 'nr_io_queues' into 'q_count', modifies
'nr_io_queues' during MSI-X setup, then resets 'nr_io_queues' for
MSI setup. Instead, copy 'nr_io_queues' into 'vecs' and modify 'vecs'
during both MSI-X and MSI setup.
This lets us simplify the for-loops that set up MSI-X and MSI, and opens
the possibility of using more I/O queues than we have interrupt vectors,
should future benchmarking prove that to be a useful feature.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Use kzalloc instead of kmalloc and a susbsequent memset.
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Pull btrfs fixes from Chris Mason:
"This is an assortment of crash fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: stop all workers before cleaning up roots
Btrfs: fix use-after-free bug during umount
Btrfs: init relocate extent_io_tree with a mapping
btrfs: Drop inode if inode root is NULL
Btrfs: don't delete fs_roots until after we cleanup the transaction
This branch contains the following bug fixes:
- Fix locking vs. interrupts. Bug caught by lockdep checks
- Fix parsing of cpp #line directive output by dtc
- Fix 'make clean' for dtc temporary files.
There is also a commit that regenerates the dtc lexer and parser files
with Bison 2.5. The only purpose of this commit is to separate the
functional change in the dtc bug fix from the code generation change
caused by a different Bison version.
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Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux
Pull device tree bug fixes from Grant Likely:
"This branch contains the following bug fixes:
- Fix locking vs. interrupts. Bug caught by lockdep checks
- Fix parsing of cpp #line directive output by dtc
- Fix 'make clean' for dtc temporary files.
There is also a commit that regenerates the dtc lexer and parser files
with Bison 2.5. The only purpose of this commit is to separate the
functional change in the dtc bug fix from the code generation change
caused by a different Bison version"
* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux:
dtc: ensure #line directives don't consume data from the next line
dtc: Update generated files to output from Bison 2.5
of: Fix locking vs. interrupts
kbuild: make sure we clean up DTB temporary files
Previously, the #line parsing regex ended with ({WS}+[0-9]+)?. The {WS}
could match line-break characters. If the #line directive did not contain
the optional flags field at the end, this could cause any integer data on
the next line to be consumed as part of the #line directive parsing. This
could cause syntax errors (i.e. #line parsing consuming the leading 0
from a hex literal 0x1234, leaving x1234 to be parsed as cell data,
which is a syntax error), or invalid compilation results (i.e. simply
consuming literal 1234 as part of the #line processing, thus removing it
from the cell data).
Fix this by replacing {WS} with [ \t] so that it can't match line-breaks.
Convert all instances of {WS}, even though the other instances should be
irrelevant for any well-formed #line directive. This is done for
consistency and ultimate safety.
[Cherry picked from DTC commit a1ee6f068e1c8dbc62873645037a353d7852d5cc]
Reported-by: Ian Campbell <Ian.Campbell@citrix.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch merely updates the generated dtc parser and lexer files to
the output generated by Bison 2.5. The previous versions were generated
from version 2.4.1. The only reason for this commit is to minimize the
diff on the next commit which fixes a bug in the DTC #line directive
parsing. Otherwise the Bison changes would be intermingled with the
functional changes.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The OF code uses irqsafe locks everywhere except in a handful of functions
for no obvious reasons. Since the conversion from the old rwlocks, this
now triggers lockdep warnings when used at interrupt time. At least one
driver (ibmvscsi) seems to be doing that from softirq context.
This converts the few non-irqsafe locks into irqsafe ones, making them
consistent with the rest of the code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Various temporary files used when building DTB files were not suffixed with
.tmp and therefore were not cleaned up by "make clean".
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
- ACPI fix for an issue causing ACPI video driver to attempt to bind
to devices it shouldn't touch from Rafael J Wysocki.
/
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Merge tag 'acpi-3.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fix from Rafael Wysocki:
"This is an alternative fix for the regression introduced in 3.9 whose
previous fix had to be reverted right before 3.10-rc5, because it
broke one of the Tony's machines.
In this one the check is confined to the ACPI video driver (which is
the only one causing the problem to happen in the first place) and the
Tony's box shouldn't even notice it.
- ACPI fix for an issue causing ACPI video driver to attempt to bind
to devices it shouldn't touch from Rafael J Wysocki."
* tag 'acpi-3.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / video: Do not bind to device objects with a scan handler
Pull x86 fixes from Peter Anvin:
"Another set of fixes, the biggest bit of this is yet another tweak to
the UEFI anti-bricking code; apparently we finally got some feedback
from Samsung as to what makes at least their systems fail. This set
should actually fix the boot regressions that some other systems (e.g.
SGI) have exhibited.
Other than that, there is a patch to avoid a panic with particularly
unhappy memory layouts and two minor protocol fixes which may or may
not be manifest bugs"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Fix typo in kexec register clearing
x86, relocs: Move __vvar_page from S_ABS to S_REL
Modify UEFI anti-bricking code
x86: Fix adjust_range_size_mask calling position
Pull RCU fixes from Paul McKenney:
"I must confess that this past merge window was not RCU's best showing.
This series contains three more fixes for RCU regressions:
1. A fix to __DECLARE_TRACE_RCU() that causes it to act as an
interrupt from idle rather than as a task switch from idle.
This change is needed due to the recent use of _rcuidle()
tracepoints that can be invoked from interrupt handlers as well
as from idle. Without this fix, invoking _rcuidle() tracepoints
from interrupt handlers results in splats and (more seriously)
confusion on RCU's part as to whether a given CPU is idle or not.
This confusion can in turn result in too-short grace periods and
therefore random memory corruption.
2. A fix to a subtle deadlock that could result due to RCU doing
a wakeup while holding one of its rcu_node structure's locks.
Although the probability of occurrence is low, it really
does happen. The fix, courtesy of Steven Rostedt, uses
irq_work_queue() to avoid the deadlock.
3. A fix to a silent deadlock (invisible to lockdep) due to the
interaction of timeouts posted by RCU debug code enabled by
CONFIG_PROVE_RCU_DELAY=y, grace-period initialization, and CPU
hotplug operations. This will not occur in production kernels,
but really does occur in randconfig testing. Diagnosis courtesy
of Steven Rostedt"
* 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
rcu: Fix deadlock with CPU hotplug, RCU GP init, and timer migration
rcu: Don't call wakeup() with rcu_node structure ->lock held
trace: Allow idle-safe tracepoints to be called from irq
Pull s390 fixes from Martin Schwidefsky:
"Three kvm related memory management fixes, a fix for show_trace, a fix
for early console output and a patch from Ben to help prevent compile
errors in regard to irq functions (or our lack thereof)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/pci: Implement IRQ functions if !PCI
s390/sclp: fix new line detection
s390/pgtable: make pgste lock an explicit barrier
s390/pgtable: Save pgste during modify_prot_start/commit
s390/dumpstack: fix address ranges for asynchronous and panic stack
s390/pgtable: Fix guest overindication for change bit
As well as the usual driver specifics we've got a couple of core fixes
here, one fixing capabilities for unidirectional streams and the other
fixing suspend while audio streams are active. The suspend fix is a
little involved but mostly as a result of removing some special casing
that was doing the wrong thing.
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Merge tag 'asoc-v3.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound
Pull ASoC sound updates from Mark Brown:
"Takashi is travelling at the minute and it'd be good to get the
MAINTAINERS update in here merged so sending directly.
As well as the usual driver specifics we've got a couple of core fixes
here, one fixing capabilities for unidirectional streams and the other
fixing suspend while audio streams are active.
The suspend fix is a little involved but mostly as a result of
removing some special casing that was doing the wrong thing."
* tag 'asoc-v3.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound:
ASoC: tlv320aic3x: Remove deadlock from snd_soc_dapm_put_volsw_aic3x()
ASoC: dapm: Treat DAI widgets like AIF widgets for power
ASoC: arizona: Correct AEC loopback enable
ASoC: pcm: Require both CODEC and CPU support when declaring stream caps
MAINTAINERS: Remove myself from Wolfson maintainers
ASoC: wm8994: Ensure microphone detection state is reset on removal
ASoC: wm8994: Avoid leaking pm_runtime reference on removed jack race
ASoC: cs42l52: fix hp_gain_enum shift value.
ASoC: cs42l52: use correct PCM mixer TLV dB scale to match datasheet.
Some tagged for -stable.
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Merge tag 'md-3.10-fixes' of git://neil.brown.name/md
Pull md bugfixes from Neil Brown:
"A few bugfixes for md
Some tagged for -stable"
* tag 'md-3.10-fixes' of git://neil.brown.name/md:
md/raid1,5,10: Disable WRITE SAME until a recovery strategy is in place
md/raid1,raid10: use freeze_array in place of raise_barrier in various places.
md/raid1: consider WRITE as successful only if at least one non-Faulty and non-rebuilding drive completed it.
md: md_stop_writes() should always freeze recovery.
On platforms with C8-C10 support, the additional C-states cause
turbostat to overrun its output buffer of 128 bytes per CPU. Increase
this to 256 bytes per CPU.
[ As a bugfix, this should go into 3.10; however, since the C8-C10
support didn't go in until after 3.9, this need not go into any stable
kernel. ]
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
few users were reporting boot regressions in v3.9. This has now been
fixed with a more accurate "minimum storage requirement to avoid
bricking" value from Samsung (5K instead of 50%) and code to trigger
garbage collection when we near our limit - Matthew Garrett.
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Merge tag 'efi-urgent' into x86/urgent
* More tweaking to the EFI variable anti-bricking algorithm. Quite a
few users were reporting boot regressions in v3.9. This has now been
fixed with a more accurate "minimum storage requirement to avoid
bricking" value from Samsung (5K instead of 50%) and code to trigger
garbage collection when we near our limit - Matthew Garrett.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
There are cases where the kernel will believe that the WRITE SAME
command is supported by a block device which does not, in fact,
support WRITE SAME. This currently happens for SATA drivers behind a
SAS controller, but there are probably a hundred other ways that can
happen, including drive firmware bugs.
After receiving an error for WRITE SAME the block layer will retry the
request as a plain write of zeroes, but mdraid will consider the
failure as fatal and consider the drive failed. This has the effect
that all the mirrors containing a specific set of data are each
offlined in very rapid succession resulting in data loss.
However, just bouncing the request back up to the block layer isn't
ideal either, because the whole initial request-retry sequence should
be inside the write bitmap fence, which probably means that md needs
to do its own conversion of WRITE SAME to write zero.
Until the failure scenario has been sorted out, disable WRITE SAME for
raid1, raid5, and raid10.
[neilb: added raid5]
This patch is appropriate for any -stable since 3.7 when write_same
support was added.
Cc: stable@vger.kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Various places in raid1 and raid10 are calling raise_barrier when they
really should call freeze_array.
The former is only intended to be called from "make_request".
The later has extra checks for 'nr_queued' and makes a call to
flush_pending_writes(), so it is safe to call it from within the
management thread.
Using raise_barrier will sometimes deadlock. Using freeze_array
should not.
As 'freeze_array' currently expects one request to be pending (in
handle_read_error - the only previous caller), we need to pass
it the number of pending requests (extra) to ignore.
The deadlock was made particularly noticeable by commits
050b66152f (raid10) and 6b740b8d79 (raid1) which
appeared in 3.4, so the fix is appropriate for any -stable
kernel since then.
This patch probably won't apply directly to some early kernels and
will need to be applied by hand.
Cc: stable@vger.kernel.org
Reported-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Without that fix, the following scenario could happen:
- RAID1 with drives A and B; drive B was freshly-added and is rebuilding
- Drive A fails
- WRITE request arrives to the array. It is failed by drive A, so
r1_bio is marked as R1BIO_WriteError, but the rebuilding drive B
succeeds in writing it, so the same r1_bio is marked as
R1BIO_Uptodate.
- r1_bio arrives to handle_write_finished, badblocks are disabled,
md_error()->error() does nothing because we don't fail the last drive
of raid1
- raid_end_bio_io() calls call_bio_endio()
- As a result, in call_bio_endio():
if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
clear_bit(BIO_UPTODATE, &bio->bi_flags);
this code doesn't clear the BIO_UPTODATE flag, and the whole master
WRITE succeeds, back to the upper layer.
So we returned success to the upper layer, even though we had written
the data onto the rebuilding drive only. But when we want to read the
data back, we would not read from the rebuilding drive, so this data
is lost.
[neilb - applied identical change to raid10 as well]
This bug can result in lost data, so it is suitable for any
-stable kernel.
Cc: stable@vger.kernel.org
Signed-off-by: Alex Lyakas <alex@zadarastorage.com>
Signed-off-by: NeilBrown <neilb@suse.de>
__md_stop_writes() will currently sometimes freeze recovery.
So any caller must be ready for that to happen, and indeed they are.
However if __md_stop_writes() doesn't freeze_recovery, then
a recovery could start before mddev_suspend() is called, which
could be awkward. This can particularly cause problems or dm-raid.
So change __md_stop_writes() to always freeze recovery. This is safe
and more predicatable.
Reported-by: Brassow Jonathan <jbrassow@redhat.com>
Tested-by: Brassow Jonathan <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Pull networking update from David Miller:
1) Fix dump iterator in nfnl_acct_dump() and ctnl_timeout_dump() to
dump all objects properly, from Pablo Neira Ayuso.
2) xt_TCPMSS must use the default MSS of 536 when no MSS TCP option is
present. Fix from Phil Oester.
3) qdisc_get_rtab() looks for an existing matching rate table and uses
that instead of creating a new one. However, it's key matching is
incomplete, it fails to check to make sure the ->data[] array is
identical too. Fix from Eric Dumazet.
4) ip_vs_dest_entry isn't fully initialized before copying back to
userspace, fix from Dan Carpenter.
5) Fix ubuf reference counting regression in vhost_net, from Jason
Wang.
6) When sock_diag dumps a socket filter back to userspace, we have to
translate it out of the kernel's internal representation first.
From Nicolas Dichtel.
7) davinci_mdio holds a spinlock while calling pm_runtime, which
sleeps. Fix from Sebastian Siewior.
8) Timeout check in sh_eth_check_reset is off by one, from Sergei
Shtylyov.
9) If sctp socket init fails, we can NULL deref during cleanup. Fix
from Daniel Borkmann.
10) netlink_mmap() does not propagate errors properly, from Patrick
McHardy.
11) Disable powersave and use minstrel by default in ath9k. From Sujith
Manoharan.
12) Fix a regression in that SOCK_ZEROCOPY is not set on tuntap sockets
which prevents vhost from being able to use zerocopy. From Jason
Wang.
13) Fix race between port lookup and TX path in team driver, from Jiri
Pirko.
14) Missing length checks in bluetooth L2CAP packet parsing, from Johan
Hedberg.
15) rtlwifi fails to connect to networking using any encryption method
other than WPA2. Fix from Larry Finger.
16) Fix iwlegacy build due to incorrect CONFIG_* ifdeffing for power
management stuff. From Yijing Wang.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (35 commits)
b43: stop format string leaking into error msgs
ath9k: Use minstrel rate control by default
Revert "ath9k_hw: Update rx gain initval to improve rx sensitivity"
ath9k: Disable PowerSave by default
net: wireless: iwlegacy: fix build error for il_pm_ops
rtlwifi: Fix a false leak indication for PCI devices
wl12xx/wl18xx: scan all 5ghz channels
wl12xx: increase minimum singlerole firmware version required
wl12xx: fix minimum required firmware version for wl127x multirole
rtlwifi: rtl8192cu: Fix problem in connecting to WEP or WPA(1) networks
mwifiex: debugfs: Fix out of bounds array access
Bluetooth: Fix mgmt handling of power on failures
Bluetooth: Fix missing length checks for L2CAP signalling PDUs
Bluetooth: btmrvl: support Marvell Bluetooth device SD8897
Bluetooth: Fix checks for LE support on LE-only controllers
team: fix checks in team_get_first_port_txable_rcu()
team: move add to port list before port enablement
team: check return value of team_get_port_by_index_rcu() for NULL
tuntap: set SOCK_ZEROCOPY flag during open
netlink: fix error propagation in netlink_mmap()
...
Pull input layer bugfix from Jiri Kosina:
"Memory leak regression fix from Benjamin Tissoires"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
HID: multitouch: prevent memleak with the allocated name
Pull block layer fixes from Jens Axboe:
"Outside of bcache (which really isn't super big), these are all
few-liners. There are a few important fixes in here:
- Fix blk pm sleeping when holding the queue lock
- A small collection of bcache fixes that have been done and tested
since bcache was included in this merge window.
- A fix for a raid5 regression introduced with the bio changes.
- Two important fixes for mtip32xx, fixing an oops and potential data
corruption (or hang) due to wrong bio iteration on stacked devices."
* 'for-linus' of git://git.kernel.dk/linux-block:
scatterlist: sg_set_buf() argument must be in linear mapping
raid5: Initialize bi_vcnt
pktcdvd: silence static checker warning
block: remove refs to XD disks from documentation
blkpm: avoid sleep when holding queue lock
mtip32xx: Correctly handle bio->bi_idx != 0 conditions
mtip32xx: Fix NULL pointer dereference during module unload
bcache: Fix error handling in init code
bcache: clarify free/available/unused space
bcache: drop "select CLOSURES"
bcache: Fix incompatible pointer type warning
Merge misc fixes from Andrew Morton:
"Bunch of fixes and one little addition to math64.h"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (27 commits)
include/linux/math64.h: add div64_ul()
mm: memcontrol: fix lockless reclaim hierarchy iterator
frontswap: fix incorrect zeroing and allocation size for frontswap_map
kernel/audit_tree.c:audit_add_tree_rule(): protect `rule' from kill_rules()
mm: migration: add migrate_entry_wait_huge()
ocfs2: add missing lockres put in dlm_mig_lockres_handler
mm/page_alloc.c: fix watermark check in __zone_watermark_ok()
drivers/misc/sgi-gru/grufile.c: fix info leak in gru_get_config_info()
aio: fix io_destroy() regression by using call_rcu()
rtc-at91rm9200: use shadow IMR on at91sam9x5
rtc-at91rm9200: add shadow interrupt mask
rtc-at91rm9200: refactor interrupt-register handling
rtc-at91rm9200: add configuration support
rtc-at91rm9200: add match-table compile guard
fs/ocfs2/namei.c: remove unecessary ERROR when removing non-empty directory
swap: avoid read_swap_cache_async() race to deadlock while waiting on discard I/O completion
drivers/rtc/rtc-twl.c: fix missing device_init_wakeup() when booted with device tree
cciss: fix broken mutex usage in ioctl
audit: wait_for_auditd() should use TASK_UNINTERRUPTIBLE
drivers/rtc/rtc-cmos.c: fix accidentally enabling rtc channel
...
There is div64_long() to handle the s64/long division, but no mocro do
u64/ul division. It is necessary in some scenarios, so add this
function.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alex Shi <alex.shi@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The lockless reclaim hierarchy iterator currently has a misplaced
barrier that can lead to use-after-free crashes.
The reclaim hierarchy iterator consist of a sequence count and a
position pointer that are read and written locklessly, with memory
barriers enforcing ordering.
The write side sets the position pointer first, then updates the
sequence count to "publish" the new position. Likewise, the read side
must read the sequence count first, then the position. If the sequence
count is up to date, it's guaranteed that the position is up to date as
well:
writer: reader:
iter->position = position if iter->sequence == expected:
smp_wmb() smp_rmb()
iter->sequence = sequence position = iter->position
However, the read side barrier is currently misplaced, which can lead to
dereferencing stale position pointers that no longer point to valid
memory. Fix this.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: <stable@kernel.org> [3.10+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The bitmap accessed by bitops must have enough size to hold the required
numbers of bits rounded up to a multiple of BITS_PER_LONG. And the
bitmap must not be zeroed by memset() if the number of bits cleared is
not a multiple of BITS_PER_LONG.
This fixes incorrect zeroing and allocation size for frontswap_map. The
incorrect zeroing part doesn't cause any problem because frontswap_map
is freed just after zeroing. But the wrongly calculated allocation size
may cause the problem.
For 32bit systems, the allocation size of frontswap_map is about twice
as large as required size. For 64bit systems, the allocation size is
smaller than requeired if the number of bits is not a multiple of
BITS_PER_LONG.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
audit_add_tree_rule() must set 'rule->tree = NULL;' firstly, to protect
the rule itself freed in kill_rules().
The reason is when it is killed, the 'rule' itself may have already
released, we should not access it. one example: we add a rule to an
inode, just at the same time the other task is deleting this inode.
The work flow for adding a rule:
audit_receive() -> (need audit_cmd_mutex lock)
audit_receive_skb() ->
audit_receive_msg() ->
audit_receive_filter() ->
audit_add_rule() ->
audit_add_tree_rule() -> (need audit_filter_mutex lock)
...
unlock audit_filter_mutex
get_tree()
...
iterate_mounts() -> (iterate all related inodes)
tag_mount() ->
tag_trunk() ->
create_trunk() -> (assume it is 1st rule)
fsnotify_add_mark() ->
fsnotify_add_inode_mark() -> (add mark to inode->i_fsnotify_marks)
...
get_tree(); (each inode will get one)
...
lock audit_filter_mutex
The work flow for deleting an inode:
__destroy_inode() ->
fsnotify_inode_delete() ->
__fsnotify_inode_delete() ->
fsnotify_clear_marks_by_inode() -> (get mark from inode->i_fsnotify_marks)
fsnotify_destroy_mark() ->
fsnotify_destroy_mark_locked() ->
audit_tree_freeing_mark() ->
evict_chunk() ->
...
tree->goner = 1
...
kill_rules() -> (assume current->audit_context == NULL)
call_rcu() -> (rule->tree != NULL)
audit_free_rule_rcu() ->
audit_free_rule()
...
audit_schedule_prune() -> (assume current->audit_context == NULL)
kthread_run() -> (need audit_cmd_mutex and audit_filter_mutex lock)
prune_one() -> (delete it from prue_list)
put_tree(); (match the original get_tree above)
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Eric Paris <eparis@redhat.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>
When we have a page fault for the address which is backed by a hugepage
under migration, the kernel can't wait correctly and do busy looping on
hugepage fault until the migration finishes. As a result, users who try
to kick hugepage migration (via soft offlining, for example) occasionally
experience long delay or soft lockup.
This is because pte_offset_map_lock() can't get a correct migration entry
or a correct page table lock for hugepage. This patch introduces
migration_entry_wait_huge() to solve this.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <stable@vger.kernel.org> [2.6.35+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dlm_mig_lockres_handler() is missing a dlm_lockres_put() on an error path.
Signed-off-by: joyce <xuejiufei@huawei.com>
Reviewed-by: shencanquan <shencanquan@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The watermark check consists of two sub-checks. The first one is:
if (free_pages <= min + lowmem_reserve)
return false;
The check assures that there is minimal amount of RAM in the zone. If
CMA is used then the free_pages is reduced by the number of free pages
in CMA prior to the over-mentioned check.
if (!(alloc_flags & ALLOC_CMA))
free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES);
This prevents the zone from being drained from pages available for
non-movable allocations.
The second check prevents the zone from getting too fragmented.
for (o = 0; o < order; o++) {
free_pages -= z->free_area[o].nr_free << o;
min >>= 1;
if (free_pages <= min)
return false;
}
The field z->free_area[o].nr_free is equal to the number of free pages
including free CMA pages. Therefore the CMA pages are subtracted twice.
This may cause a false positive fail of __zone_watermark_ok() if the CMA
area gets strongly fragmented. In such a case there are many 0-order
free pages located in CMA. Those pages are subtracted twice therefore
they will quickly drain free_pages during the check against
fragmentation. The test fails even though there are many free non-cma
pages in the zone.
This patch fixes this issue by subtracting CMA pages only for a purpose of
(free_pages <= min + lowmem_reserve) check.
Laura said:
We were observing allocation failures of higher order pages (order 5 =
128K typically) under tight memory conditions resulting in driver
failure. The output from the page allocation failure showed plenty of
free pages of the appropriate order/type/zone and mostly CMA pages in
the lower orders.
For full disclosure, we still observed some page allocation failures
even after applying the patch but the number was drastically reduced and
those failures were attributed to fragmentation/other system issues.
Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: <stable@vger.kernel.org> [3.7+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The "info.fill" array isn't initialized so it can leak uninitialized stack
information to user space.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Robin Holt <holt@sgi.com>
Acked-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There was a regression introduced by 36f5588905 ("aio: refcounting
cleanup"), reported by Jens Axboe - the refcounting cleanup switched to
using RCU in the shutdown path, but the synchronize_rcu() was done in
the context of the io_destroy() syscall greatly increasing the time it
could block.
This patch switches it to call_rcu() and makes shutdown asynchronous
(more asynchronous than it was originally; before the refcount changes
io_destroy() would still wait on pending kiocbs).
Note that there's a global quota on the max outstanding kiocbs, and that
quota must be manipulated synchronously; otherwise io_setup() could
return -EAGAIN when there isn't quota available, and userspace won't
have any way of waiting until shutdown of the old kioctxs has finished
(besides busy looping).
So we release our quota before kioctx shutdown has finished, which
should be fine since the quota never corresponded to anything real
anyways.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Reported-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Tested-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for the at91sam9x5-family which must use the shadow
interrupt mask due to a hardware issue (causing RTC_IMR to always be
zero).
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add shadow interrupt-mask register which can be used on SoCs where the
actual hardware register is broken.
Note that some care needs to be taken to make sure the shadow mask
corresponds to the actual hardware state. The added overhead is not an
issue for the non-broken SoCs due to the relatively infrequent
interrupt-mask updates. We do, however, only use the shadow mask value
as a fall-back when it actually needed as there is still a theoretical
possibility that the mask is incorrect (see the code for details).
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add accessors for the interrupt register.
This will allow us to easily add a shadow interrupt-mask register to use
on SoCs where the interrupt-mask register cannot be used.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add configuration support which can be used to implement SoC-specific
workarounds for broken hardware.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The members of Atmel's at91sam9x5 family (9x5) have a broken RTC
interrupt mask register (AT91_RTC_IMR). It does not reflect enabled
interrupts but instead always returns zero.
The kernel's rtc-at91rm9200 driver handles the RTC for the 9x5 family.
Currently when the date/time is set, an interrupt is generated and this
driver neglects to handle the interrupt. The kernel complains about the
un-handled interrupt and disables it henceforth. This not only breaks
the RTC function, but since that interrupt is shared (Atmel's SYS
interrupt) then other things break as well (e.g. the debug port no
longer accepts characters).
Tested on the at91sam9g25. Bug confirmed by Atmel.
This patch (of 5):
Add missing match-table compile guard.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Robert Nelson <Robert.Nelson@digikey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While removing a non-empty directory, the kernel dumps a message:
(rmdir,21743,1):ocfs2_unlink:953 ERROR: status = -39
Suppress the error message from being printed in the dmesg so users
don't panic.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Acked-by: Sunil Mushran <sunil.mushran@gmail.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
read_swap_cache_async() can race against get_swap_page(), and stumble
across a SWAP_HAS_CACHE entry in the swap map whose page wasn't brought
into the swapcache yet.
This transient swap_map state is expected to be transitory, but the
actual placement of discard at scan_swap_map() inserts a wait for I/O
completion thus making the thread at read_swap_cache_async() to loop
around its -EEXIST case, while the other end at get_swap_page() is
scheduled away at scan_swap_map(). This can leave the system deadlocked
if the I/O completion happens to be waiting on the CPU waitqueue where
read_swap_cache_async() is busy looping and !CONFIG_PREEMPT.
This patch introduces a cond_resched() call to make the aforementioned
read_swap_cache_async() busy loop condition to bail out when necessary,
thus avoiding the subtle race window.
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
