Otherwise, "ls -l" will simply show the ownership of the files as
the default mnt_uid/gid. This may make "ls -l" performance on large
directories super-suck in some cases, but that's the cost of cifsacl.
One possibility to make it suck less would be to somehow proactively
dispatch the ACL requests asynchronously from readdir codepath, but
that's non-trivial to implement.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
The option to have a blank "pass=" already exists, and with
a password specified both "pass=%s" and "password=%s" are supported.
Also, both blank "user=" and "username=" are supported, making
"password=" the odd man out.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
This patch enables optional for original SMB2 (SMB2.02) dialect
by specifying vers=2.0 on mount.
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
If we netogiate mandatory locking style, have a read lock and try
to set a write lock we end up with a write lock in vfs cache and
no lock in cifs lock cache - that's wrong. Fix it by returning
from cifs_setlk immediately if a error occurs during setting a lock.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
that reacquires byte-range locks when a file is reopened.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
because the is no difference here. This also adds support of prefixpath
mount option for SMB2.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Error out with a clear error message if there is no unc= option. The
existing code doesn't handle this in a clear fashion, and the check for
a UNCip option with no UNC string is just plain wrong.
Later, we'll fix the code to not require a unc= option, but for now we
need this to at least clarify why people are getting errors about DFS
parsing. With this change we can also get rid of some later NULL pointer
checks since we know the UNC and UNCip will never be NULL there.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
If we're using cifsacl, then we don't want to override the uid/gid with
the current uid/gid, since that would prevent you from being able to
upcall for this info.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
...and make those symbols static in cifsacl.c. Nothing outside
of that file refers to them.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
The format specifiers are for signed values, but these are unsigned.
Given that '-' is a delimiter between fields, I don't think you'd get
what you'd expect if you got a value here that would overflow the sign
bit.
The version and authority fields are 8 bit values so use a "hh" length
modifier there. The subauths are 32 bit values, so there's no need to
use a "l" length modifier there.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
According to several places on the Internet and the samba winbind code,
this is hard limited to 15 in windows, not 5. This does balloon out
the allocation of each by 40 bytes, but I don't see any alternative.
Also, rename it to SID_MAX_SUB_AUTHORITIES to match the alleged name
of this constant in the windows header files
Finally, rename SIDLEN to SID_STRING_MAX, fix the value to reflect
the change to SID_MAX_SUB_AUTHORITIES and document how it was
determined.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
...and lift the restriction in id_to_sid upcall that the size must be
at least as big as a full cifs_sid.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
..nothing outside of cifsacl.c calls it. Also fix the incorrect
comment on the function. It returns 0 when they match.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
...instead of hardcoding in '5' and '6' all over the place.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Add a label we can goto on error, and get rid of some excess indentation.
Also move to kernel-style comments.
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Most of these are unsigned ints, so we should be passing "uint" to
module_param. Also, get rid of the extra "(bool)" in the description
of enable_oplocks.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
We had planned to upgrade to ntlmv2 security a few releases ago,
and have been warning users in dmesg on mount about the impending
upgrade, but had to make a change (to use nltmssp with ntlmv2) due
to testing issues with some non-Windows, non-Samba servers.
The approach in this patch is simpler than earlier patches,
and changes the default authentication mechanism to ntlmv2
password hashes (encapsulated in ntlmssp) from ntlm (ntlm is
too weak for current use and ntlmv2 has been broadly
supported for many, many years).
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
READ is zero so the "rw & READ" test is always false. The intended test
was "((rw & RW_MASK) == READ)".
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull module fixes from Rusty Russell:
"Module signing build fixes for blackfin and metag"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
modsign: add symbol prefix to certificate list
linux/kernel.h: define SYMBOL_PREFIX
code:
1. The UBI background thread got stuck when a bit-flip happened because free
LEBs was not removed from the "free" tree when we started using it.
2. I/O debugging checks did not work because we called a sleeping function in
atomic context.
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Merge tag 'upstream-3.7-rc9' of git://git.infradead.org/linux-ubi
Pull UBI changes from Artem Bityutskiy:
"Fixes for 2 brown-paperbag bugs introduced this merge window by the
fastmap code:
1. The UBI background thread got stuck when a bit-flip happened
because free LEBs was not removed from the "free" tree when we
started using it.
2. I/O debugging checks did not work because we called a sleeping
function in atomic context."
* tag 'upstream-3.7-rc9' of git://git.infradead.org/linux-ubi:
UBI: dont call ubi_self_check_all_ff() in __wl_get_peb()
UBI: remove PEB from free tree in get_peb_for_wl()
Pull workqueue fixes from Tejun Heo:
"So, safe fixes my ass.
Commit 8852aac25e ("workqueue: mod_delayed_work_on() shouldn't queue
timer on 0 delay") had the side-effect of performing delayed_work
sanity checks even when @delay is 0, which should be fine for any sane
use cases.
Unfortunately, megaraid was being overly ingenious. It seemingly
wanted to use cancel_delayed_work_sync() before cancel_work_sync() was
introduced, but didn't want to waste the space for full delayed_work
as it was only going to use 0 @delay. So, it only allocated space for
struct work_struct and then cast it to struct delayed_work and passed
it into delayed_work functions - truly awesome engineering tradeoff to
save some bytes.
Xiaotian fixed it by making megraid allocate full delayed_work for
now. It should be converted to use work_struct and cancel_work_sync()
but I think we better do that after 3.7.
I added another commit to change BUG_ON()s in __queue_delayed_work()
to WARN_ON_ONCE()s so that the kernel doesn't crash even if there are
more such abuses."
* 'for-3.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: convert BUG_ON()s in __queue_delayed_work() to WARN_ON_ONCE()s
megaraid: fix BUG_ON() from incorrect use of delayed work
Pull sparc fixes from David Miller:
"Two small fixes for Sparc, nobody uses sparc, so these are low risk :-)
1) Piggyback is too picky about the symbol types that _start and _end
have in the final kernel image, and it thus breaks with newer
binutils. Future proof by getting rid of the symbol type checks.
2) exit_group() should kill register windows on sparc64 the same way
we do for plain exit(). Thanks to Al Viro for spotting this."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc: Fix piggyback with newer binutils.
sparc64: exit_group should kill register windows just like plain exit.
The block device access simplification that avoided accessing the (racy)
block size information (commit bbec0270bd: "blkdev_max_block: make
private to fs/buffer.c") no longer checks the maximum block size in the
block mapping path.
That was _almost_ as simple as just removing the code entirely, because
the readers and writers all check the size of the device anyway, so
under normal circumstances it "just worked".
However, the block size may be such that the end of the device may
straddle one single buffer_head. At which point we may still want to
access the end of the device, but the buffer we use to access it
partially extends past the end.
The 'bd_set_size()' function intentionally sets the block size to avoid
this, but mounting the device - or setting the block size by hand to
some other value - can modify that block size.
So instead, teach 'submit_bh()' about the special case of the buffer
head straddling the end of the device, and turning such an access into a
smaller IO access, avoiding the problem.
This, btw, also means that unlike before, we can now access the whole
device regardless of device block size setting. So now, even if the
device size is only 512-byte aligned, we can read and write even the
last sector even when having a much bigger block size for accessing the
rest of the device.
So with this, we could now get rid of the 'bd_set_size()' block size
code entirely - resulting in faster IO for the common case - but that
would be a separate patch.
Reported-and-tested-by: Romain Francoise <romain@orebokech.com>
Reporeted-and-tested-by: Meelis Roos <mroos@linux.ee>
Reported-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
8852aac25e ("workqueue: mod_delayed_work_on() shouldn't queue timer on
0 delay") unexpectedly uncovered a very nasty abuse of delayed_work in
megaraid - it allocated work_struct, casted it to delayed_work and
then pass that into queue_delayed_work().
Previously, this was okay because 0 @delay short-circuited to
queue_work() before doing anything with delayed_work. 8852aac25e
moved 0 @delay test into __queue_delayed_work() after sanity check on
delayed_work making megaraid trigger BUG_ON().
Although megaraid is already fixed by c1d390d8e6 ("megaraid: fix
BUG_ON() from incorrect use of delayed work"), this patch converts
BUG_ON()s in __queue_delayed_work() to WARN_ON_ONCE()s so that such
abusers, if there are more, trigger warning but don't crash the
machine.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Xiaotian Feng <xtfeng@gmail.com>
megaraid use INIT_WORK to declare a hotplug_work, but cast the
hotplug_work from work_struct to delayed_work and
schedule_delayed_work on it. This is very dangerous, as other part of
delayed_work might be kernel memories allocated by others.
With commit 8852aac ("workqueue: mod_delayed_work_on() shouldn't queue
timer on 0 delay"), schedule_delayed_work() will check dwork->timer
before queue_work even when @delay is 0, this causes megaraid code to
hit the BUG_ON() in workqueue code. Change megaraid code to use
delayed work.
Signed-off-by: Xiaotian Feng <dannyfeng@tencent.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Neela Syam Kolli <megaraidlinux@lsi.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: linux-scsi@vger.kernel.org
As ubi_self_check_all_ff() might sleep we are not allowed
to call it from atomic context.
For now we call it only from ubi_wl_get_peb().
There are some code paths where it would also make sense,
but these paths are currently atomic and only enabled
when fastmap is used.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
If UBI is built without fastmap, get_peb_for_wl() has to
remove the PEB manially from the free tree.
Otherwise the requested PEB lives in two trees.
Reported-by: Zach Sadecki <zsadecki@itwatchdogs.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Newer versions of binutils mark '_end' as 'B' instead of 'A' for
whatever reason.
To be honest, the piggyback code doesn't actually care what kind
of symbol _start and _end are, it just wants to find them and
record the address.
So remove the type from the match strings.
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull media fixes from Mauro Carvalho Chehab:
"Some driver fixes for s5p/exynos (mostly race fixes)"
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] s5p-mfc: Handle multi-frame input buffer
[media] s5p-mfc: Bug fix of timestamp/timecode copy mechanism
[media] exynos-gsc: Add missing video device vfl_dir flag initialization
[media] exynos-gsc: Fix settings for input and output image RGB type
[media] exynos-gsc: Don't use mutex_lock_interruptible() in device release()
[media] fimc-lite: Don't use mutex_lock_interruptible() in device release()
[media] s5p-fimc: Don't use mutex_lock_interruptible() in device release()
[media] s5p-fimc: Prevent race conditions during subdevs registration
In commit 9d73fc2d64 ("open*(2) compat fixes (s390, arm64)") I said:
>
> The usual rules for open()/openat()/open_by_handle_at() are
> 1) native 32bit - don't force O_LARGEFILE in flags
> 2) native 64bit - force O_LARGEFILE in flags
> 3) compat on 64bit host - as for native 32bit
> 4) native 32bit ABI for 64bit system (mips/n32, x86/x32) - as for native 64bit
>
> There are only two exceptions - s390 compat has open() forcing O_LARGEFILE and
> arm64 compat has open_by_handle_at() doing the same thing. The same binaries
> on native host (s390/31 and arm resp.) will *not* force O_LARGEFILE, so IMO
> both are emulation bugs.
Three exceptions, actually - parisc open() is another case like that.
Native 32bit won't force O_LARGEFILE, the same binary on parisc64 will.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge 'block-dev' branch.
I was going to just mark everything here for stable and leave it to the
3.8 merge window, but having decided on doing another -rc, I migth as
well merge it now.
This removes the bd_block_size_semaphore semaphore that was added in
this release to fix a race condition between block size changes and
block IO, and replaces it with atomicity guaratees in fs/buffer.c
instead, along with simplifying fs/block-dev.c.
This removes more lines than it adds, makes the code generally simpler,
and avoids the latency/rt issues that the block size semaphore
introduced for mount.
I'm not happy with the timing, but it wouldn't be much better doing this
during the merge window and then having some delayed back-port of it
into stable.
* block-dev:
blkdev_max_block: make private to fs/buffer.c
direct-io: don't read inode->i_blkbits multiple times
blockdev: remove bd_block_size_semaphore again
fs/buffer.c: make block-size be per-page and protected by the page lock
Add the arch symbol prefix (if applicable) to the asm definition of
modsign_certificate_list and modsign_certificate_list_end. This uses the
recently defined SYMBOL_PREFIX which is derived from
CONFIG_SYMBOL_PREFIX.
This fixes the build of module signing on the blackfin and metag
architectures.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Define SYMBOL_PREFIX to be the same as CONFIG_SYMBOL_PREFIX if set by
the architecture, or "" otherwise. This avoids the need for ugly #ifdefs
whenever symbols are referenced in asm blocks.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Pull networking fixes from David Miller:
1) 8139cp leaks memory in error paths, from Francois Romieu.
2) do_tcp_sendpages() cannot handle order > 0 pages, but they can
certainly arrive there now, fix from Eric Dumazet.
3) Race condition and sysfs fixes in bonding from Nikolay Aleksandrov.
4) Remain-on-Channel fix in mac80211 from Felix Liao.
5) CCK rate calculation fix in iwlwifi, from Emmanuel Grumbach.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
8139cp: fix coherent mapping leak in error path.
tcp: fix crashes in do_tcp_sendpages()
bonding: fix race condition in bonding_store_slaves_active
bonding: make arp_ip_target parameter checks consistent with sysfs
bonding: fix miimon and arp_interval delayed work race conditions
mac80211: fix remain-on-channel (non-)cancelling
iwlwifi: fix the basic CCK rates calculation
The usual rules for open()/openat()/open_by_handle_at() are
1) native 32bit - don't force O_LARGEFILE in flags
2) native 64bit - force O_LARGEFILE in flags
3) compat on 64bit host - as for native 32bit
4) native 32bit ABI for 64bit system (mips/n32, x86/x32) - as for
native 64bit
There are only two exceptions - s390 compat has open() forcing
O_LARGEFILE and arm64 compat has open_by_handle_at() doing the same
thing. The same binaries on native host (s390/31 and arm resp.) will
*not* force O_LARGEFILE, so IMO both are emulation bugs.
Objections? The fix is obvious...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull late workqueue fixes from Tejun Heo:
"Unfortunately, I have two really late fixes. One was for a
long-standing bug and queued for 3.8 but I found out about a
regression introduced during 3.7-rc1 two days ago, so I'm sending out
the two fixes together.
The first (long-standing) one is rescuer_thread() entering exit path
w/ TASK_INTERRUPTIBLE. It only triggers on workqueue destructions
which isn't very frequent and the exit path can usually survive being
called with TASK_INTERRUPT, so it was hidden pretty well. Apparently,
if you're reiserfs, this could lead to the exiting kthread sleeping
indefinitely holding a mutex, which is never good.
The fix is simple - restoring TASK_RUNNING before returning from the
kthread function.
The second one is introduced by the new mod_delayed_work().
mod_delayed_work() was missing special case handling for 0 delay.
Instead of queueing the work item immediately, it queued the timer
which expires on the closest next tick. Some users of the new
function converted from "[__]cancel_delayed_work() +
queue_delayed_work()" combination became unhappy with the extra delay.
Block unplugging led to noticeably higher number of context switches
and intel 6250 wireless failed to associate with WPA-Enterprise
network. The fix, again, is fairly simple. The 0 delay special case
logic from queue_delayed_work_on() should be moved to
__queue_delayed_work() which is shared by both queue_delayed_work_on()
and mod_delayed_work_on().
The first one is difficult to trigger and the failure mode for the
latter isn't completely catastrophic, so missing these two for 3.7
wouldn't make it a disastrous release, but both bugs are nasty and the
fixes are fairly safe"
* 'for-3.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: mod_delayed_work_on() shouldn't queue timer on 0 delay
workqueue: exit rescuer_thread() as TASK_RUNNING
cp_open
[...]
rc = cp_alloc_rings(cp);
if (rc)
return rc;
cp_alloc_rings
[...]
mem = dma_alloc_coherent(&cp->pdev->dev, CP_RING_BYTES,
&cp->ring_dma, GFP_KERNEL);
- cp_alloc_rings never frees the coherent mapping it allocates
- neither do cp_open when cp_alloc_rings fails
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Recent network changes allowed high order pages being used
for skb fragments.
This uncovered a bug in do_tcp_sendpages() which was assuming its caller
provided an array of order-0 page pointers.
We only have to deal with a single page in this function, and its order
is irrelevant.
Reported-by: Willy Tarreau <w@1wt.eu>
Tested-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
8376fe22c7 ("workqueue: implement mod_delayed_work[_on]()")
implemented mod_delayed_work[_on]() using the improved
try_to_grab_pending(). The function is later used, among others, to
replace [__]candel_delayed_work() + queue_delayed_work() combinations.
Unfortunately, a delayed_work item w/ zero @delay is handled slightly
differently by mod_delayed_work_on() compared to
queue_delayed_work_on(). The latter skips timer altogether and
directly queues it using queue_work_on() while the former schedules
timer which will expire on the closest tick. This means, when @delay
is zero, that [__]cancel_delayed_work() + queue_delayed_work_on()
makes the target item immediately executable while
mod_delayed_work_on() may induce delay of upto a full tick.
This somewhat subtle difference breaks some of the converted users.
e.g. block queue plugging uses delayed_work for deferred processing
and uses mod_delayed_work_on() when the queue needs to be immediately
unplugged. The above problem manifested as noticeably higher number
of context switches under certain circumstances.
The difference in behavior was caused by missing special case handling
for 0 delay in mod_delayed_work_on() compared to
queue_delayed_work_on(). Joonsoo Kim posted a patch to add it -
("workqueue: optimize mod_delayed_work_on() when @delay == 0")[1].
The patch was queued for 3.8 but it was described as optimization and
I missed that it was a correctness issue.
As both queue_delayed_work_on() and mod_delayed_work_on() use
__queue_delayed_work() for queueing, it seems that the better approach
is to move the 0 delay special handling to the function instead of
duplicating it in mod_delayed_work_on().
Fix the problem by moving 0 delay special case handling from
queue_delayed_work_on() to __queue_delayed_work(). This replaces
Joonsoo's patch.
[1] http://thread.gmane.org/gmane.linux.kernel/1379011/focus=1379012
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Anders Kaseorg <andersk@MIT.EDU>
Reported-and-tested-by: Zlatko Calusic <zlatko.calusic@iskon.hr>
LKML-Reference: <alpine.DEB.2.00.1211280953350.26602@dr-wily.mit.edu>
LKML-Reference: <50A78AA9.5040904@iskon.hr>
Cc: Joonsoo Kim <js1304@gmail.com>
A rescue thread exiting TASK_INTERRUPTIBLE can lead to a task scheduling
off, never to be seen again. In the case where this occurred, an exiting
thread hit reiserfs homebrew conditional resched while holding a mutex,
bringing the box to its knees.
PID: 18105 TASK: ffff8807fd412180 CPU: 5 COMMAND: "kdmflush"
#0 [ffff8808157e7670] schedule at ffffffff8143f489
#1 [ffff8808157e77b8] reiserfs_get_block at ffffffffa038ab2d [reiserfs]
#2 [ffff8808157e79a8] __block_write_begin at ffffffff8117fb14
#3 [ffff8808157e7a98] reiserfs_write_begin at ffffffffa0388695 [reiserfs]
#4 [ffff8808157e7ad8] generic_perform_write at ffffffff810ee9e2
#5 [ffff8808157e7b58] generic_file_buffered_write at ffffffff810eeb41
#6 [ffff8808157e7ba8] __generic_file_aio_write at ffffffff810f1a3a
#7 [ffff8808157e7c58] generic_file_aio_write at ffffffff810f1c88
#8 [ffff8808157e7cc8] do_sync_write at ffffffff8114f850
#9 [ffff8808157e7dd8] do_acct_process at ffffffff810a268f
[exception RIP: kernel_thread_helper]
RIP: ffffffff8144a5c0 RSP: ffff8808157e7f58 RFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8107af60 RDI: ffff8803ee491d18
RBP: 0000000000000000 R8: 0000000000000000 R9: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
Signed-off-by: Mike Galbraith <mgalbraith@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Pull vfs fixes from Al Viro:
"A bunch of fixes; the last one is this cycle regression, the rest are
-stable fodder."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fix off-by-one in argument passed by iterate_fd() to callbacks
lookup_one_len: don't accept . and ..
cifs: get rid of blind d_drop() in readdir
nfs_lookup_revalidate(): fix a leak
don't do blind d_drop() in nfs_prime_dcache()
Pull RCU fix from Ingo Molnar:
"Fix leaking RCU extended quiescent state, which might trigger warnings
and mess up the extended quiescent state tracking logic into thinking
that we are in "RCU user mode" while we aren't."
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rcu: Fix unrecovered RCU user mode in syscall_trace_leave()
