If we had to fall back to read/write through MDS, then assume that we should
retry pNFS after a suitable timeout period.
The following patch sets a timeout of 2 minutes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Dereferencing nfsi->layout in order to read plh_flags without holding
a spin lock is bug prone. Furthermore, the dprintk() tells you nothing
about whether or not the call succeeded.
Replace it with something that tells you about whether or not a valid
layout segment was returned for the inode in question.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that we do return errors from nfs4_proc_layoutget() and that we
don't mark the layout as having failed if the error was due to a
signal or resource problem on the client side.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is only set after everyone has dereferenced the transport,
and serves no useful purpose: setting it is racy, so all the
socket code, etc still needs to be able to cope with the cases
where they miss reading it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is to ensure that we don't clear the NFS_CONTEXT_RESEND_WRITES
flag while there are still writes that haven't been resent.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the server reboots before it can commit the unstable writes to disk,
then nfs_commit_release_pages() will detect this when it compares the
verifier returned by COMMIT to the one returned by WRITE. When this
happens, the client needs to resend those writes in order to guarantee
that they make it to stable storage.
This patch adds a signalling mechanism to notify fsync() that it
needs to retry all writes before it can exit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to be able to pass on the information that the page was not
dirtied under a lock. Instead of adding a flag parameter, do this
by passing a pointer to a 'struct nfs_lock_owner' that may be NULL.
Also reuse this structure in struct nfs_lock_context to carry the
fl_owner_t and pid_t.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to be able to distinguish between allocation failures, and
the case where the lock context is not needed (because there are no
locks).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We only have to call xdr_shrink_pagelen() if the remaining RPC
message does not fit in the page buffer length that we supplied
to xdr_align_pages().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The callers of xdr_align_pages() expect it to return the number of bytes
of actual XDR data remaining in the pages.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In nfs4_create_sec_client, 'flavor' can hold a negative error
code (returned from nfs4_negotiate_security), even though it
is an 'enum' and hence unsigned.
The code is careful to cast it to an (int) before testing if it
is negative, however it doesn't cast to an (int) before calling
ERR_PTR.
On a machine where "void*" is larger than "int", this results in
the unsigned equivalent of -1 (e.g. 0xffffffff) being converted
to a pointer. Subsequent code determines that this is not
negative, and so dereferences it with predictable results.
So: cast 'flavor' to a (signed) int before passing to ERR_PTR.
cc: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In case of error, the function rpcauth_create() returns ERR_PTR()
and never returns NULL pointer. The NULL test in the return value
check should be replaced with IS_ERR().
dpatch engine is used to auto generated this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Instead of doing a shutdown() call, we need to do an actual close().
Ditto if/when the server is sending us junk RPC headers.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Simon Kirby <sim@hostway.ca>
Cc: stable@vger.kernel.org
Pull block fixes from Jens Axboe:
"A small collection of driver fixes/updates and a core fix for 3.6. It
contains:
- Bug fixes for mtip32xx, and support for new hardware (just addition
of IDs). They have been queued up for 3.7 for a few weeks as well.
- rate-limit a failing command error message in block core.
- A fix for an old cciss bug from Stephen.
- Prevent overflow of partition count from Alan."
* 'for-linus' of git://git.kernel.dk/linux-block:
cciss: fix handling of protocol error
blk: add an upper sanity check on partition adding
mtip32xx: fix user_buffer check in exec_drive_command
mtip32xx: Remove dead code
mtip32xx: Change printk to pr_xxxx
mtip32xx: Proper reporting of write protect status on big-endian
mtip32xx: Increase timeout for standby command
mtip32xx: Handle NCQ commands during the security locked state
mtip32xx: Add support for new devices
block: rate-limit the error message from failing commands
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Merge tag 'sh-for-linus' of git://github.com/pmundt/linux-sh
Pull SuperH fixes from Paul Mundt.
* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
sh: Fix up TIF_NOTIFY_RESUME sans TIF_SIGPENDING handling.
sh: pfc: Release spinlock in sh_pfc_gpio_request_enable() error path
sh: intc: Fix up multi-evt irq association.
One reverts a recent patch which turns out to not be such a good
idea.
Other two fix minor bugs with the new (since 3.3) 'replacement' code
and have been tagged for -stable.
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Merge tag 'md-3.6-fixes' of git://neil.brown.name/md
Pull md fixes from NeilBrown:
"3 fixes for md in 3.6.
One reverts a recent patch which turns out to not be such a good idea.
Other two fix minor bugs with the new (since 3.3) 'replacement' code
and have been tagged for -stable."
* tag 'md-3.6-fixes' of git://neil.brown.name/md:
md: make sure metadata is updated when spares are activated or removed.
md/raid5: fix calculate of 'degraded' when a replacement becomes active.
Revert "md/raid5: For odirect-write performance, do not set STRIPE_PREREAD_ACTIVE."
Pull workqueue / powernow-k8 fix from Tejun Heo:
"This is the fix for the bug where cpufreq/powernow-k8 was tripping
BUG_ON() in try_to_wake_up_local() by migrating workqueue worker to a
different CPU.
https://bugzilla.kernel.org/show_bug.cgi?id=47301
As discussed, the fix is now two parts - one to reimplement
work_on_cpu() so that it doesn't create a new kthread each time and
the actual fix which makes powernow-k8 use work_on_cpu() instead of
performing manual migration.
While pretty late in the merge cycle, both changes are on the safer
side. Jiri and I verified two existing users of work_on_cpu() and
Duncan confirmed that the powernow-k8 fix survived about 18 hours of
testing."
* 'for-3.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
cpufreq/powernow-k8: workqueue user shouldn't migrate the kworker to another CPU
workqueue: reimplement work_on_cpu() using system_wq
powernowk8_target() runs off a per-cpu work item and if the
cpufreq_policy->cpu is different from the current one, it migrates the
kworker to the target CPU by manipulating current->cpus_allowed. The
function migrates the kworker back to the original CPU but this is
still broken. Workqueue concurrency management requires the kworkers
to stay on the same CPU and powernowk8_target() ends up triggerring
BUG_ON(rq != this_rq()) in try_to_wake_up_local() if it contends on
fidvid_mutex and sleeps.
It is unclear why this bug is being reported now. Duncan says it
appeared to be a regression of 3.6-rc1 and couldn't reproduce it on
3.5. Bisection seemed to point to 63d95a91 "workqueue: use @pool
instead of @gcwq or @cpu where applicable" which is an non-functional
change. Given that the reproduce case sometimes took upto days to
trigger, it's easy to be misled while bisecting. Maybe something made
contention on fidvid_mutex more likely? I don't know.
This patch fixes the bug by using work_on_cpu() instead if @pol->cpu
isn't the same as the current one. The code assumes that
cpufreq_policy->cpu is kept online by the caller, which Rafael tells
me is the case.
stable: ed48ece27c ("workqueue: reimplement work_on_cpu() using
system_wq") should be applied before this; otherwise, the
behavior could be horrible.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Duncan <1i5t5.duncan@cox.net>
Tested-by: Duncan <1i5t5.duncan@cox.net>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: stable@vger.kernel.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=47301
The existing work_on_cpu() implementation is hugely inefficient. It
creates a new kthread, execute that single function and then let the
kthread die on each invocation.
Now that system_wq can handle concurrent executions, there's no
advantage of doing this. Reimplement work_on_cpu() using system_wq
which makes it simpler and way more efficient.
stable: While this isn't a fix in itself, it's needed to fix a
workqueue related bug in cpufreq/powernow-k8. AFAICS, this
shouldn't break other existing users.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: stable@vger.kernel.org
It isn't always necessary to update the metadata when spares are
removed as the presence-or-not of a spare isn't really important to
the integrity of an array.
Also activating a spare doesn't always require updating the metadata
as the update on 'recovery-completed' is usually sufficient.
However the introduction of 'replacement' devices have made these
transitions sometimes more important. For example the 'Replacement'
flag isn't cleared until the original device is removed, so we need
to ensure a metadata update after that 'spare' is removed.
So set MD_CHANGE_DEVS whenever a spare is activated or removed, to
complement the current situation where it is set when a spare is added
or a device is failed (or a number of other less common situations).
This is suitable for -stable as out-of-data metadata could lead
to data corruption.
This is only relevant for 3.3 and later 9when 'replacement' as
introduced.
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
When a replacement device becomes active, we mark the device that it
replaces as 'faulty' so that it can subsequently get removed.
However 'calc_degraded' only pays attention to the primary device, not
the replacement, so the array appears to become degraded, which is
wrong.
So teach 'calc_degraded' to consider any replacement if a primary
device is faulty.
This is suitable for -stable as an incorrect 'degraded' value can
confuse md and could lead to data corruption.
This is only relevant for 3.3 and later.
Cc: stable@vger.kernel.org
Reported-by: Robin Hill <robin@robinhill.me.uk>
Reported-by: John Drescher <drescherjm@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This reverts commit 895e3c5c58.
While this patch seemed like a good idea and did help some workloads,
it hurts other workloads.
Large sequential O_DIRECT writes were faster,
Small random O_DIRECT writes were slower.
Other changes (batching RAID5 writes) have improved the sequential
writes using a different mechanism, so the net result of this patch
is definitely negative. So revert it.
Reported-by: Shaohua Li <shli@kernel.org>
Tested-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
IBM reported a soft lockup after applying the fix for the rename_lock
deadlock. Commit c83ce989cb ("VFS: Fix the nfs sillyrename regression
in kernel 2.6.38") was found to be the culprit.
The nfs sillyrename fix used DCACHE_DISCONNECTED to indicate that the
dentry was killed. This flag can be set on non-killed dentries too,
which results in infinite retries when trying to traverse the dentry
tree.
This patch introduces a separate flag: DCACHE_DENTRY_KILLED, which is
only set in d_kill() and makes try_to_ascend() test only this flag.
IBM reported successful test results with this patch.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a command completes with a status of CMD_PROTOCOL_ERR, this
information should be conveyed to the SCSI mid layer, not dropped
on the floor. Unlike a similar bug in the hpsa driver, this bug
only affects tape drives and CD and DVD ROM drives in the cciss
driver, and to induce it, you have to disconnect (or damage) a
cable, so it is not a very likely scenario (which would explain
why the bug has gone undetected for the last 10 years.)
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
65536 should be ludicrous anyway but without it we overflow the
memory computation doing the allocation and badness occurs.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
As Al notes, we missed a TIF_NOTIFY_RESUME check which caused any
handlers without TIF_SIGPENDING also set to skip the notification:
Looks like while it is in the relevant masks *and* checked in
do_notify_resume() both on 32bit and 64bit variants since commit
ab99c733ae ("sh: Make syscall tracer
use tracehook notifiers, add TIF_NOTIFY_RESUME.") they are
actually *not* reached without simulataneous SIGPENDING, since
the actual glue in the callers had not been updated back then and
still checks for _TIF_SIGPENDING alone when deciding whether to
hit do_notify_resume() or not.
Reported-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The sh_pfc_gpio_request_enable() function acquires a spinlock but fails
to release it before returning if the requested mux type is not
supported. Fix this.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Pull another workqueue fix from Tejun Heo:
"Unfortunately, yet another late fix. This too is discovered and fixed
by Lai. This bug was introduced during this merge window by commit
25511a4776 ("workqueue: reimplement CPU online rebinding to handle
idle workers") which started using WORKER_REBIND flag for idle rebind
too.
The bug is relatively easy to trigger if the CPU rapidly goes through
off, on and then off (and stay off). The fix is on the safer side.
This hasn't been on linux-next yet but I'm pushing early so that it
can get more exposure before v3.6 release."
* 'for-3.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: always clear WORKER_REBIND in busy_worker_rebind_fn()
Merge fixes from Andrew Morton:
"13 patches. 12 are fixes and one is a little preparatory thing for
Andi."
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (13 commits)
memory hotplug: fix section info double registration bug
mm/page_alloc: fix the page address of higher page's buddy calculation
drivers/rtc/rtc-twl.c: ensure all interrupts are disabled during probe
compiler.h: add __visible
pid-namespace: limit value of ns_last_pid to (0, max_pid)
include/net/sock.h: squelch compiler warning in sk_rmem_schedule()
slub: consider pfmemalloc_match() in get_partial_node()
slab: fix starting index for finding another object
slab: do ClearSlabPfmemalloc() for all pages of slab
nbd: clear waiting_queue on shutdown
MAINTAINERS: fix TXT maintainer list and source repo path
mm/ia64: fix a memory block size bug
memory hotplug: reset pgdat->kswapd to NULL if creating kernel thread fails
There may be a bug when registering section info. For example, on my
Itanium platform, the pfn range of node0 includes the other nodes, so
other nodes' section info will be double registered, and memmap's page
count will equal to 3.
node0: start_pfn=0x100, spanned_pfn=0x20fb00, present_pfn=0x7f8a3, => 0x000100-0x20fc00
node1: start_pfn=0x80000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x080000-0x100000
node2: start_pfn=0x100000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x100000-0x180000
node3: start_pfn=0x180000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x180000-0x200000
free_all_bootmem_node()
register_page_bootmem_info_node()
register_page_bootmem_info_section()
When hot remove memory, we can't free the memmap's page because
page_count() is 2 after put_page_bootmem().
sparse_remove_one_section()
free_section_usemap()
free_map_bootmem()
put_page_bootmem()
[akpm@linux-foundation.org: add code comment]
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The heuristic method for buddy has been introduced since commit
43506fad21 ("mm/page_alloc.c: simplify calculation of combined index
of adjacent buddy lists"). But the page address of higher page's buddy
was wrongly calculated, which will lead page_is_buddy to fail for ever.
IOW, the heuristic method would be disabled with the wrong page address
of higher page's buddy.
Calculating the page address of higher page's buddy should be based
higher_page with the offset between index of higher page and index of
higher page's buddy.
Signed-off-by: Haifeng Li <omycle@gmail.com>
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: KyongHo Cho <pullip.cho@samsung.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: <stable@vger.kernel.org> [2.6.38+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On some platforms, bootloaders are known to do some interesting RTC
programming. Without going into the obscurities as to why this may be
the case, suffice it to say the the driver should not make any
assumptions about the state of the RTC when the driver loads. In
particular, the driver probe should be sure that all interrupts are
disabled until otherwise programmed.
This was discovered when finding bursty I2C traffic every second on
Overo platforms. This I2C overhead was keeping the SoC from hitting
deep power states. The cause was found to be the RTC firing every
second on the I2C-connected TWL PMIC.
Special thanks to Felipe Balbi for suggesting to look for a rogue driver
as the source of the I2C traffic rather than the I2C driver itself.
Special thanks to Steve Sakoman for helping track down the source of the
continuous RTC interrups on the Overo boards.
Signed-off-by: Kevin Hilman <khilman@ti.com>
Cc: Felipe Balbi <balbi@ti.com>
Tested-by: Steve Sakoman <steve@sakoman.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Tested-by: Shubhrajyoti Datta <omaplinuxkernel@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc 4.6+ has support for a externally_visible attribute that prevents the
optimizer from optimizing unused symbols away. Add a __visible macro to
use it with that compiler version or later.
This is used (at least) by the "Link Time Optimization" patchset.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel doesn't check the pid for negative values, so if you try to
write -2 to /proc/sys/kernel/ns_last_pid, you will get a kernel panic.
The crash happens because the next pid is -1, and alloc_pidmap() will
try to access to a nonexistent pidmap.
map = &pid_ns->pidmap[pid/BITS_PER_PAGE];
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This warning:
In file included from linux/include/linux/tcp.h:227:0,
from linux/include/linux/ipv6.h:221,
from linux/include/net/ipv6.h:16,
from linux/include/linux/sunrpc/clnt.h:26,
from linux/net/sunrpc/stats.c:22:
linux/include/net/sock.h: In function `sk_rmem_schedule':
linux/nfs-2.6/include/net/sock.h:1339:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
is seen with gcc (GCC) 4.6.3 20120306 (Red Hat 4.6.3-2) using the
-Wextra option.
Commit c76562b670 ("netvm: prevent a stream-specific deadlock")
accidentally replaced the "size" parameter of sk_rmem_schedule() with an
unsigned int. This changes the semantics of the comparison in the
return statement.
In sk_wmem_schedule we have syntactically the same comparison, but
"size" is a signed integer. In addition, __sk_mem_schedule() takes a
signed integer for its "size" parameter, so there is an implicit type
conversion in sk_rmem_schedule() anyway.
Revert the "size" parameter back to a signed integer so that the
semantics of the expressions in both sk_[rw]mem_schedule() are exactly
the same.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: David Miller <davem@davemloft.net>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
get_partial() is currently not checking pfmemalloc_match() meaning that
it is possible for pfmemalloc pages to leak to non-pfmemalloc users.
This is a problem in the following situation. Assume that there is a
request from normal allocation and there are no objects in the per-cpu
cache and no node-partial slab.
In this case, slab_alloc enters the slow path and new_slab_objects() is
called which may return a PFMEMALLOC page. As the current user is not
allowed to access PFMEMALLOC page, deactivate_slab() is called
([5091b74a: mm: slub: optimise the SLUB fast path to avoid pfmemalloc
checks]) and returns an object from PFMEMALLOC page.
Next time, when we get another request from normal allocation,
slab_alloc() enters the slow-path and calls new_slab_objects(). In
new_slab_objects(), we call get_partial() and get a partial slab which
was just deactivated but is a pfmemalloc page. We extract one object
from it and re-deactivate.
"deactivate -> re-get in get_partial -> re-deactivate" occures repeatedly.
As a result, access to PFMEMALLOC page is not properly restricted and it
can cause a performance degradation due to frequent deactivation.
deactivation frequently.
This patch changes get_partial_node() to take pfmemalloc_match() into
account and prevents the "deactivate -> re-get in get_partial()
scenario. Instead, new_slab() is called.
Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: David Miller <davem@davemloft.net>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In array cache, there is a object at index 0, check it.
Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: David Miller <davem@davemloft.net>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Right now, we call ClearSlabPfmemalloc() for first page of slab when we
clear SlabPfmemalloc flag. This is fine for most swap-over-network use
cases as it is expected that order-0 pages are in use. Unfortunately it
is possible that that __ac_put_obj() checks SlabPfmemalloc on a tail
page and while this is harmless, it is sloppy. This patch ensures that
the head page is always used.
This problem was originally identified by Joonsoo Kim.
[js1304@gmail.com: Original implementation and problem identification]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: David Miller <davem@davemloft.net>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a serious but uncommon bug in nbd which occurs when there is heavy
I/O going to the nbd device while, at the same time, a failure (server,
network) or manual disconnect of the nbd connection occurs.
There is a small window between the time that the nbd_thread is stopped
and the socket is shutdown where requests can continue to be queued to
nbd's internal waiting_queue. When this happens, those requests are
never completed or freed.
The fix is to clear the waiting_queue on shutdown of the nbd device, in
the same way that the nbd request queue (queue_head) is already being
cleared.
Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Trond Myklebust