The charging code can encounter a charge size that is bigger than a
regular page in two situations: one is a batched charge to fill the
per-cpu stocks, the other is a huge page charge.

This code is distributed over two functions, however, and only the outer
one is aware of huge pages.  In case the charging fails, the inner
function will tell the outer function to retry if the charge size is
bigger than regular pages--assuming batched charging is the only case.
And the outer function will retry forever charging a huge page.

This patch makes sure the inner function can distinguish between batch
charging and a single huge page charge.  It will only signal another
attempt if batch charging failed, and go into regular reclaim when it is
called on behalf of a huge page.
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: NMinchan Kim <minchan.kim@gmail.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When a tail page of THP is poisoned, memory-failure will do nothing except
setting PG_hwpoison, while the expected behavior is that the process, who
is using the poisoned tail page, should be killed.

The above problem is caused by lru check of the poisoned tail page of THP.
Because PG_lru flag is only set on the head page of THP, the check always
consider the poisoned tail page as NON lru page.

So the lru check for the tail page of THP should be avoided, as like as
hugetlb.

This patch adds !PageTransCompound() before lru check for THP, because of
the check (!PageHuge() && !PageTransCompound()) the whole branch could be
optimized away at build time when both hugetlbfs and THP are set with "N"
(or in archs not supporting either of those).

[akpm@linux-foundation.org: fix unrelated typo in shake_page() comment]
Signed-off-by: NJin Dongming <jin.dongming@np.css.fujitsu.com>
Reviewed-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When the tail page of THP is poisoned, the head page will be poisoned too.
 And the wrong address, address of head page, will be sent with sigbus
always.

So when the poisoned page is used by Guest OS which is running on KVM,
after the address changing(hva->gpa) by qemu, the unexpected process on
Guest OS will be killed by sigbus.

What we expected is that the process using the poisoned tail page could be
killed on Guest OS, but not that the process using the healthy head page
is killed.

Since it is not good to poison the healthy page, avoid poisoning other
than the page which is really poisoned.
  (While we poison all pages in a huge page in case of hugetlb,
   we can do this for THP thanks to split_huge_page().)

Here we fix two parts:
  1. Isolate the poisoned page only to make sure
     the reported address is the address of poisoned page.
  2. make the poisoned page work as the poisoned regular page.

[akpm@linux-foundation.org: fix spello in comment]
Signed-off-by: NJin Dongming <jin.dongming@np.css.fujitsu.com>
Reviewed-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The poisoned THP is now split with split_huge_page() in
collect_procs_anon().  If kmalloc() is failed in collect_procs(),
split_huge_page() could not be called.  And the work after
split_huge_page() for collecting the processes using poisoned page will
not be done, too.  So the processes using the poisoned page could not be
killed.

The condition becomes worse when CONFIG_DEBUG_VM == "Y".  Because the
poisoned THP could not be split, system panic will be caused by
VM_BUG_ON(PageTransHuge(page)) in try_to_unmap().

This patch does:
  1. move split_huge_page() to the place before collect_procs().
     This can be sure the failure of splitting THP is caused by itself.
  2. when splitting THP is failed, stop the operations after it.
     This can avoid unexpected system panic or non sense works.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NJin Dongming <jin.dongming@np.css.fujitsu.com>
Reviewed-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The support@simtec.co.uk address is for direct customer support only, the
EB2410ITX and EB110ATX entries should direct to the Simtec Linux Team
address of linux@simtec.co.uk

Also add correct email address for Vincent Sanders

[akpm@linux-foundation.org: fix Vincent's address]
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Cc: Vincent Sanders <vince@simtec.co.uk>
Cc: Simtec Support <support@simtec.co.uk>
Cc: Simtec Linux Team <linux@simtec.co.uk>
Cc: Jack Stone <jwjstone@fastmail.fm>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add the correct files for the Simtec BAST machine, ensuring the IDE and
IRQ routing are added, and move to the machine specific file instead of
trying to catch all of arch/arm/mach-s3c2410
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Cc: Simtec Linux Team <linux@simtec.co.uk>
Cc: Simtec Support <support@simtec.co.uk>
Cc: Jack Stone <jwjstone@fastmail.fm>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are currently two entries under the "SIMTEC EB2410ITX (BAST)"
machine entry for drivers/*/*s3c2410*, which is catching everything
s3c2410 driver related.

This entry is for a specific S3C2410 based machine, so move these two file
entries to the "ARM/SAMSUNG ARM ARCHITECTURES" entry, where it will reach
a wider audience of interested parties.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Cc: Simtec Linux Team <linux@simtec.co.uk>
Acked-by: NKukjin Kim <kgene.kim@samsung.com>
Cc: Jack Stone <jwjstone@fastmail.fm>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

commit 95aac7b1 ("epoll: make epoll_wait() use the hrtimer range
feature") added a performance regression because it uses timespec_add_ns()
with potential very large 'ns' values.

[akpm@linux-foundation.org: s/epoll_set_mstimeout/ep_set_mstimeout/, per Davide]
Reported-by: NSimon Kirby <sim@hostway.ca>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Shawn Bohrer <shawn.bohrer@gmail.com>
Acked-by: NDavide Libenzi <davidel@xmailserver.org>
Cc: <stable@kernel.org>		[2.6.37.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If migrate_huge_page by memory-failure fails , it calls put_page in itself
to decrease page reference and caller of migrate_huge_page also calls
putback_lru_pages.  It can do double free of page so it can make page
corruption on page holder.

In addtion, clean of pages on caller is consistent behavior with
migrate_pages by cf608ac1 ("mm: compaction: fix COMPACTPAGEFAILED
counting").
Signed-off-by: NMinchan Kim <minchan.kim@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In some cases migrate_pages could return zero while still leaving a few
pages in the pagelist (and some caller wouldn't notice it has to call
putback_lru_pages after commit cf608ac1 ("mm: compaction: fix
COMPACTPAGEFAILED counting")).

Add one missing putback_lru_pages not added by commit cf608ac1 ("mm:
compaction: fix COMPACTPAGEFAILED counting").
Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Signed-off-by: NMinchan Kim <minchan.kim@gmail.com>
Reviewed-by: NMinchan Kim <minchan.kim@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

noswapaccount couldn't be used to control memsw for both on/off cases so
we have added swapaccount[=0|1] parameter.  This way we can turn the
feature in two ways noswapaccount resp.  swapaccount=0.  We have kept the
original noswapaccount but I think we should remove it after some time as
it just makes more command line parameters without any advantages and also
the code to handle parameters is uglier if we want both parameters.
Signed-off-by: NMichal Hocko <mhocko@suse.cz>
Requested-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

__setup based kernel command line parameters handlers which are handled in
obsolete_checksetup are provided with the parameter value including =
(more precisely everything right after the parameter name).

This means that the current implementation of swapaccount[=1|0] doesn't
work at all because if there is a value for the parameter then we are
testing for "0" resp.  "1" but we are getting "=0" resp.  "=1" and if
there is no parameter value we are getting an empty string rather than
NULL.

The original noswapccount parameter, which doesn't care about the value,
works correctly.
Signed-off-by: NMichal Hocko <mhocko@suse.cz>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'next' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: Fix ASM optimized code for LE
  microblaze: Fix unaligned issue on MMU system with BS=0 DIV=1
  microblaze: Fix DTB passing from bootloader

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: fix length checks in checkSMB
  [CIFS] Update cifs minor version
  cifs: No need to check crypto blockcipher allocation
  cifs: clean up some compiler warnings
  cifs: make CIFS depend on CRYPTO_MD4
  cifs: force a reconnect if there are too many MIDs in flight
  cifs: don't pop a printk when sending on a socket is interrupted
  cifs: simplify SMB header check routine
  cifs: send an NT_CANCEL request when a process is signalled
  cifs: handle cancelled requests better
  cifs: fix two compiler warning about uninitialized vars

As Tao Ma noticed, change 5ecfda04 breaks blktrace. This is because
blktrace mmaps a file with PROT_WRITE permissions but without PROT_READ,
so my attempt to not unnecessarity break COW during mlock ended up
causing mlock to fail with a permission problem.

I am proposing to let mlock ignore vma protection in all cases except
PROT_NONE. In particular, mlock should not fail for PROT_WRITE regions
(as in the blktrace case, which broke at 5ecfda04) or for PROT_EXEC
regions (which seem to me like they were always broken).
Signed-off-by: NMichel Lespinasse <walken@google.com>
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The comments under "config STUB_POULSBO" are close to correct,
but they are not being followed.  This patch updates them to reflect
the requirements for THERMAL.

This build error is caused by STUB_POULSBO selecting ACPI_VIDEO
when ACPI_VIDEO's config requirements are not met.

  ERROR: "thermal_cooling_device_register" [drivers/acpi/video.ko] undefined!
  ERROR: "thermal_cooling_device_unregister" [drivers/acpi/video.ko] undefined!
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: NFSv4 readdir loses entries
  NFS: Micro-optimize nfs4_decode_dirent()
  NFS: Fix an NFS client lockdep issue
  NFS construct consistent co_ownerid for v4.1
  NFS: nfs_wcc_update_inode() should set nfsi->attr_gencount
  NFS improve pnfs_put_deviceid_cache debug print
  NFS fix cb_sequence error processing
  NFS do not find client in NFSv4 pg_authenticate
  NLM: Fix "kernel BUG at fs/lockd/host.c:417!" or ".../host.c:283!"
  NFS: Prevent memory allocation failure in nfsacl_encode()
  NFS: nfsacl_{encode,decode} should return signed integer
  NFS: Fix "kernel BUG at fs/nfs/nfs3xdr.c:1338!"
  NFS: Fix "kernel BUG at fs/aio.c:554!"
  NFS4: Avoid potential NULL pointer dereference in decode_and_add_ds().
  NFS: fix handling of malloc failure during nfs_flush_multi()

The cERROR message in checkSMB when the calculated length doesn't match
the RFC1001 length is incorrect in many cases. It always says that the
RFC1001 length is bigger than the SMB, even when it's actually the
reverse.

Fix the error message to say the reverse of what it does now when the
SMB length goes beyond the end of the received data. Also, clarify the
error message when the RFC length is too big. Finally, clarify the
comments to show that the 512 byte limit on extra data at the end of
the packet is arbitrary.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: smp_on_up: allow non-ARM SMP processors
  ARM: io: ensure inb/outb() et.al. are properly ordered on ARMv6+
  ARM: initrd: disable initrd if passed address overlaps reserved region
  ARM: footbridge: fix debug macros
  ARM: mmci: round down the bytes transferred on error
  ARM: mmci: complete the transaction on error
  ARM: 6642/1: mmci: calculate remaining bytes at error correctly

Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6

* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
  arch/arm/mach-omap2/dma.c: Convert IS_ERR result to PTR_ERR
  arm: omap2: mux: fix compile warning
  omap1: Simplify use of omap_irq_flags
  omap2+: Fix unused variable warning for omap_irq_base

Fix kernel-doc warning in kernel.h from commit 7ef88ad5
("BUILD_BUG_ON: make it handle more cases"):

  Warning(include/linux/kernel.h:605): No description found for parameter 'condition'
  Warning(include/linux/kernel.h:605): Excess function parameter 'cond' description in 'BUILD_BUG_ON'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: xfs_bmap_add_extent_delay_real should init br_startblock
  xfs: fix dquot shaker deadlock
  xfs: handle CIl transaction commit failures correctly
  xfs: limit extsize to size of AGs and/or MAXEXTLEN
  xfs: prevent extsize alignment from exceeding maximum extent size
  xfs: limit extent length for allocation to AG size
  xfs: speculative delayed allocation uses rounddown_power_of_2 badly
  xfs: fix efi item leak on forced shutdown
  xfs: fix log ticket leak on forced shutdown.

Patches should keep coming through Rusty but it helps if I'm Cc'd as
well.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'usb-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (42 commits)
  usb: gadget: composite: avoid access beyond array max length
  USB: serial: handle Data Carrier Detect changes
  USB: gadget: Fix endpoint representation in ci13xxx_udc
  USB: gadget: Fix error path in ci13xxx_udc gadget probe function
  usb: pch_udc: Fix the worning log issue at gadget driver remove
  USB: serial: Updated support for ICOM devices
  USB: ehci-mxc: add work-around for efika mx/sb bug
  USB: unbreak ehci-mxc on otg port of i.MX27
  drivers: update to pl2303 usb-serial to support Motorola cables
  USB: adding USB support for Cinterion's HC2x, EU3 and PH8 products
  USB serial: add missing .usb_driver field in serial drivers
  USB: ehci-fsl: Fix 'have_sysif_regs' detection
  USB: g_printer: fix bug in module parameter definitions
  USB: g_printer: fix bug in unregistration
  USB: uss720: remove duplicate USB device
  MAINTAINERS: add ueagle-atm entry
  USB: EHCI: fix DMA deallocation bug
  USB: pch_udc: support new device ML7213 IOH
  usb: pch_udc: Fixed issue which does not work with g_serial
  usb: set ep_dev async suspend should be later than device_initialize
  ...

* 'staging-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6: (26 commits)
  staging: r8712u: Add new device IDs
  staging: brcm80211: fix suspend/resume issue in brcmsmac
  staging: brcm80211: remove assert to avoid panic since 2.6.37 kernel
  Staging: iio: Aditional fixpoint formatted output bugfix
  staging: usbip: vhci: use urb->dev->portnum to find port
  staging: usbip: vhci: handle EAGAIN from SO_RCVTIMEO
  staging: usbip: vhci: friendly log messages for connection errors
  staging: usbip: vhci: refuse to enqueue for dead connections
  staging: usbip: vhci: give back URBs from in-flight unlink requests
  staging: usbip: vhci: update reference count for usb_device
  staging: usbip: stub: update refcounts for devices and interfaces
  staging: tidspbridge: replace mbox callback with notifier_call
  staging: comedi: ni_labpc: Use shared IRQ for PCMCIA card
  Staging: speakup: &&/|| confusion in silent_store()
  iio: Fixpoint formatted output bugfix
  staging: rt2860: Fix incorrect netif_stop_queue usage warning
  staging: r8712u: Fix memory leak in firmware loading
  staging: tidspbridge: configure full L1 MMU range
  staging: rt2870sta: Add ID for Linksys WUSB100v2
  Staging: xgfib: put parenthesis in the right place
  ...

* 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6:
  tty/serial: fix apbuart build
  n_hdlc: fix read and write locking
  serial: unbreak billionton CF card
  tty: use for_each_console() and WARN() on sysfs failures
  vt: fix issue when fbcon wants to takeover a second time.

Fix up trivial conflict in drivers/tty/tty_io.c

Signed-off-by: NSteve French <sfrench@us.ibm.com>

Allow non-ARM SMP processors to use the SMP_ON_UP feature.  CPUs
supporting SMP must have the new CPU ID format, so check for this first.
Then check for ARM11MPCore, which fails the MPIDR check.  Lastly check
the MPIDR reports multiprocessing extensions and that the CPU is part of
a multiprocessing system.

Cc: <stable@kernel.org>
Reported-and-Tested-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Missed one change as per earlier suggestion.
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

New compiler warnings that I noticed when building a patchset based
on recent Fedora kernel:

fs/cifs/cifssmb.c: In function 'CIFSSMBSetFileSize':
fs/cifs/cifssmb.c:4813:8: warning: variable 'data_offset' set but not used
[-Wunused-but-set-variable]

fs/cifs/file.c: In function 'cifs_open':
fs/cifs/file.c:349:24: warning: variable 'pCifsInode' set but not used
[-Wunused-but-set-variable]
fs/cifs/file.c: In function 'cifs_partialpagewrite':
fs/cifs/file.c:1149:23: warning: variable 'cifs_sb' set but not used
[-Wunused-but-set-variable]
fs/cifs/file.c: In function 'cifs_iovec_write':
fs/cifs/file.c:1740:9: warning: passing argument 6 of 'CIFSSMBWrite2' from
incompatible pointer type [enabled by default]
fs/cifs/cifsproto.h:337:12: note: expected 'unsigned int *' but argument is
of type 'size_t *'

fs/cifs/readdir.c: In function 'cifs_readdir':
fs/cifs/readdir.c:767:23: warning: variable 'cifs_sb' set but not used
[-Wunused-but-set-variable]

fs/cifs/cifs_dfs_ref.c: In function 'cifs_dfs_d_automount':
fs/cifs/cifs_dfs_ref.c:342:2: warning: 'rc' may be used uninitialized in
this function [-Wuninitialized]
fs/cifs/cifs_dfs_ref.c:278:6: note: 'rc' was declared here
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Recently CIFS was changed to use the kernel crypto API for MD4 hashes,
but the Kconfig dependencies were not changed to reflect this.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reported-and-Tested-by: NSuresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Ensure that the ISA/PCI IO space accessors are properly ordered on
ARMv6+ architectures.  These should always be ordered with respect to
all other accesses.

This also fixes __iormb() and __iowmb() not being visible to ioread/
iowrite if a platform defines its own MMIO accessors.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Disable the initrd if the passed address already overlaps the reserved
region.  This avoids oopses on Netwinders when NeTTrom tells the kernel
that an initrd is located at mem+4MB, but this overlaps the BSS,
resulting in the kernels in-use BSS being freed.

This should be applied to v2.6.37-stable.

Cc: <stable@kernel.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

0ea12930 (arm: return both physical and virtual addresses from addruart)
changed the way the 'addruart' worked, making it return both the virt
and phys addresses.  Unfortunately, for footbridge, these were reversed.
Fix that.  Tested on Netwinder.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We should not report incomplete blocks on error.  Return the number of
bytes successfully transferred, rounded down to the nearest block.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When we encounter an error, make sure we complete the transaction
otherwise we'll leave the request dangling.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Currently, we allow the pending_mid_q to grow without bound with
SIGKILL'ed processes. This could eventually be a DoS'able problem. An
unprivileged user could a process that does a long-running call and then
SIGKILL it.

If he can also intercept the NT_CANCEL calls or the replies from the
server, then the pending_mid_q could grow very large, possibly even to
2^16 entries which might leave GetNextMid in an infinite loop. Fix this
by imposing a hard limit of 32k calls per server. If we cross that
limit, set the tcpStatus to CifsNeedReconnect to force cifsd to
eventually reconnect the socket and clean out the pending_mid_q.

While we're at it, clean up the function a bit and eliminate an
unnecessary NULL pointer check.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

If we kill the process while it's sending on a socket then the
kernel_sendmsg will return -EINTR. This is normal. No need to spam the
ring buffer with this info.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

...just cleanup. There should be no behavior change.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>