regulator: wm831x: Set the new rather than old value for DVS VSEL

commit 13ae633cf729b0ecb677b75b04886ff8fada8fad upstream.

Reported-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ath5k: fix tx path skb leaks

commit 596ab5ec3bf10a22be30d7cb1d903a4b83fd607c upstream.

ieee80211_free_txskb() needs to be used instead of dev_kfree_skb_any for
tx packets passed to the driver from mac80211

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bcma: mips: fix clearing device IRQ

commit cbbc0138efe1dcd5426b8fc5d87741f5057aee72 upstream.

We were using wrong IRQ number so clearing wasn't working at all.
Depending on a platform this could result in a one device having two
interrupts assigned. On BCM4706 this resulted in all IRQs being broken.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc: Fix CONFIG_RELOCATABLE=y CONFIG_CRASH_DUMP=n build

commit 11ee7e99f35ecb15f59b21da6a82d96d2cd3fcc8 upstream.

If we build a kernel with CONFIG_RELOCATABLE=y CONFIG_CRASH_DUMP=n,
the kernel fails when we run at a non zero offset. It turns out
we were incorrectly wrapping some of the relocatable kernel code
with CONFIG_CRASH_DUMP.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc/vdso: Remove redundant locking in update_vsyscall_tz()

commit ce73ec6db47af84d1466402781ae0872a9e7873c upstream.

The locking in update_vsyscall_tz() is not only unnecessary because the vdso
code copies the data unproteced in __kernel_gettimeofday() but also
introduces a hard to reproduce race condition between update_vsyscall()
and update_vsyscall_tz(), which causes user space process to loop
forever in vdso code.

The following patch removes the locking from update_vsyscall_tz().

Locking is not only unnecessary because the vdso code copies the data
unprotected in __kernel_gettimeofday() but also erroneous because updating
the tb_update_count is not atomic and introduces a hard to reproduce race
condition between update_vsyscall() and update_vsyscall_tz(), which further
causes user space process to loop forever in vdso code.

The below scenario describes the race condition,
x==0	Boot CPU			other CPU
	proc_P: x==0
	    timer interrupt
		update_vsyscall
x==1		    x++;sync		settimeofday
					    update_vsyscall_tz
x==2						x++;sync
x==3		    sync;x++
						sync;x++
	proc_P: x==3 (loops until x becomes even)

Because the ++ operator would be implemented as three instructions and not
atomic on powerpc.

A similar change was made for x86 in commit 6c260d58634
("x86: vdso: Remove bogus locking in update_vsyscall_tz")

Signed-off-by: Shan Hai <shan.hai@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc: Add missing NULL terminator to avoid boot panic on PPC40x

commit e6449c9b2d90c1bd9a5985bf05ddebfd1631cd6b upstream.

The missing NULL terminator can cause a panic on
PPC405 boards during boot:

  Linux/PowerPC load: console=ttyS0,115200 root=/dev/mtdblock1 rootfstype=squashfs,jffs2 noinitrd init=/etc/preinit
  Finalizing device tree... flat tree at 0x6a5160
  bootconsole [udbg0] enabled
  Page fault in user mode with in_atomic() = 1 mm = (null)
  NIP = c0275f50  MSR = fffffffe
  Oops: Weird page fault, sig: 11 [#1]
  PowerPC 40x Platform
  Modules linked in:
  NIP: c0275f50 LR: c0275f60 CTR: c0280000
  REGS: c0275eb0 TRAP: 636f7265   Not tainted  (3.7.1)
  MSR: fffffffe <VEC,VSX,EE,PR,FP,ME,SE,BE,IR,DR,PMM,RI> CR: c06a6190  XER: 00000001
  TASK = c02662a8[0] 'swapper' THREAD: c0274000
  GPR00: c0275ec0 c000c658 c027c4bf 00000000 c0275ee0 c000a0ec c020a1a8 c020a1f0
  GPR08: c020f631 c020f404 c025f078 c025f080 c0275f10
   Call Trace:
   ---[ end trace 31fd0ba7d8756001 ]---

  Kernel panic - not syncing: Attempted to kill the idle task!

The panic happens since commit 9597abe00c1bab2aedce6b49866bf6d1e81c9eed
(sections: fix section conflicts in arch/powerpc), however the root
cause of this is that the NULL terminator were not added in commit
a4f740cf33f7f6c164bbde3c0cdbcc77b0c4997c (of/flattree: Add of_flat_dt_match()
helper function).

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
KVM: Fix user memslot overlap check

commit 5419369ed6bd4cf711fdda5e52a5999b940413f5 upstream.

Prior to memory slot sorting this loop compared all of the user memory
slots for overlap with new entries.  With memory slot sorting, we're
just checking some number of entries in the array that may or may not
be user slots.  Instead, walk all the slots with kvm_for_each_memslot,
which has the added benefit of terminating early when we hit the first
empty slot, and skip comparison to private slots.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
s390/cio: fix pgid reserved check

commit d99e79ec5574fc556c988f613ed6175f6de66f4a upstream.

The check to whom a device is reserved is done by checking the path
state of the affected channel paths. If it turns out that one path is
flagged as reserved by someone else the whole device is marked as such.

However the meaning of the RESVD_ELSE bit is that the addressed device
is reserved to a different pathgroup (and not reserved to a different
LPAR). If we do this test on a path which is currently not a member of
the pathgroup we could erroneously mark the device as reserved to
someone else.

To fix this collect the reserved state for all potential members of the
pathgroup and only mark the device as reserved if all of those potential
members have the RESVD_ELSE bit set.

Acked-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MIPS: Fix poweroff failure when HOTPLUG_CPU configured.

commit 8add1ecb81f541ef2fcb0b85a5470ad9ecfb4a84 upstream.

When poweroff machine, kernel_power_off() call disable_nonboot_cpus().
And if we have HOTPLUG_CPU configured, disable_nonboot_cpus() is not an
empty function but attempt to actually disable the nonboot cpus. Since
system state is SYSTEM_POWER_OFF, play_dead() won't be called and thus
disable_nonboot_cpus() hangs. Therefore, we make this patch to avoid
poweroff failure.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Hongliang Tao <taohl@lemote.com>
Signed-off-by: Hua Yan <yanh@lemote.com>
Cc: Yong Zhang <yong.zhang@windriver.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/4211/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm: compaction: fix echo 1 > compact_memory return error issue

commit 7964c06d66c76507d8b6b662bffea770c29ef0ce upstream.

when run the folloing command under shell, it will return error

  sh/$ echo 1 > /proc/sys/vm/compact_memory
  sh/$ sh: write error: Bad address

After strace, I found the following log:

  ...
  write(1, "1\n", 2)               = 3
  write(1, "", 4294967295)         = -1 EFAULT (Bad address)
  write(2, "echo: write error: Bad address\n", 31echo: write error: Bad address
  ) = 31

This tells system return 3(COMPACT_COMPLETE) after write data to
compact_memory.

The fix is to make the system just return 0 instead 3(COMPACT_COMPLETE)
from sysctl_compaction_handler after compaction_nodes finished.

Signed-off-by: Jason Liu <r64343@freescale.com>
Suggested-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm: use aligned zone start for pfn_to_bitidx calculation

commit c060f943d0929f3e429c5d9522290584f6281d6e upstream.

The current calculation in pfn_to_bitidx assumes that (pfn -
zone->zone_start_pfn) >> pageblock_order will return the same bit for
all pfn in a pageblock.  If zone_start_pfn is not aligned to
pageblock_nr_pages, this may not always be correct.

Consider the following with pageblock order = 10, zone start 2MB:

  pfn     | pfn - zone start | (pfn - zone start) >> page block order
  ----------------------------------------------------------------
  0x26000 | 0x25e00	   |  0x97
  0x26100 | 0x25f00	   |  0x97
  0x26200 | 0x26000	   |  0x98
  0x26300 | 0x26100	   |  0x98

This means that calling {get,set}_pageblock_migratetype on a single page
will not set the migratetype for the full block.  Fix this by rounding
down zone_start_pfn when doing the bitidx calculation.

For our use case, the effects of this bug were mostly tied to the fact
that CMA allocations would either take a long time or fail to happen.
Depending on the driver using CMA, this could result in anything from
visual glitches to application failures.

Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "ath9k_hw: Update AR9003 high_power tx gain table"

commit 9c170e068636deb3e3f96114034bb711675f0faa upstream.

This reverts commit f74b9d365ddd33a375802b064f96a5d0e99af7c0.

Turns out reverting commit a240dc7b3c7463bd60cf0a9b2a90f52f78aae0fd
"ath9k_hw: Updated AR9003 tx gain table for 5GHz" was not enough to
bring the tx power back to normal levels on devices like the
Buffalo WZR-HP-G450H, this one needs to be reverted as well.

This revert improves tx power by ~10 db on that device

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: rmanohar@qca.qualcomm.com
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ath9k: ar9003: fix OTP register offsets for AR9340

commit b3cd8021379306c0be6932e4d3b4b01efc681769 upstream.

Trying to access the OTP memory on the AR9340
causes a data bus error like this:

  Data bus error, epc == 86e84164, ra == 86e84164
  Oops[#1]:
  Cpu 0
  $ 0   : 00000000 00000061 deadc0de 00000000
  $ 4   : b8115f18 00015f18 00000007 00000004
  $ 8   : 00000001 7c7c3c7c 7c7c7c7c 7c7c7c7c
  $12   : 7c7c3c7c 001f0041 00000000 7c7c7c3c
  $16   : 86ee0000 00015f18 00000000 00000007
  $20   : 00000004 00000064 00000004 86d71c44
  $24   : 00000000 86e6ca00
  $28   : 86d70000 86d71b20 86ece0c0 86e84164
  Hi    : 00000000
  Lo    : 00000064
  epc   : 86e84164 ath9k_hw_wait+0x58/0xb0 [ath9k_hw]
      Tainted: G           O
  ra    : 86e84164 ath9k_hw_wait+0x58/0xb0 [ath9k_hw]
  Status: 1100d403    KERNEL EXL IE
  Cause : 4080801c
  PrId  : 0001974c (MIPS 74Kc)
  Modules linked in: ath9k(O+) ath9k_common(O) ath9k_hw(O) ath(O) ar934x_nfc
  mac80211(O) usbcore usb_common scsi_mod nls_base nand nand_ecc nand_ids
  crc_ccitt cfg80211(O) compat(O) arc4 aes_generic crypto_blkcipher cryptomgr
  aead crypto_hash crypto_algapi ledtrig_timer ledtrig_default_on leds_gpio
  Process insmod (pid: 459, threadinfo=86d70000, task=87942140, tls=779ac440)
  Stack : 802fb500 000200da 804db150 804e0000 87816130 86ee0000 00010000 86d71b88
          86d71bc0 00000004 00000003 86e9fcd0 80305300 0002c0d0 86e74c50 800b4c20
          000003e8 00000001 00000000 86ee0000 000003ff 86e9fd64 80305300 80123938
          fffffffc 00000004 000058bc 00000000 86ea0000 86ee0000 000001ff 878d6000
          99999999 86e9fdc0 86ee0fcc 86e9e664 0000c0d0 86ee0000 0000700000007000
          ...
  Call Trace:
  [<86e84164>] ath9k_hw_wait+0x58/0xb0 [ath9k_hw]
  [<86e9fcd0>] ath9k_hw_setup_statusring+0x16b8/0x1c7c [ath9k_hw]

  Code: 0000a812  0040f809  00000000 <00531024> 1054000b  24020001  0c05b5dc  2404000a  26520001

The cause of the error is that the OTP register
offsets are different on the AR9340 than the
actually used values.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ath9k_hw: Fix signal strength / channel noise reporting

commit b7c0c238898d200e80487516e2b67aba2a522cc0 upstream.

While AR_PHY_CCA_NOM_VAL_* does contain the expected internal noise floor
for a chip measured in clean air, it refers to the lowest expected reading.

Depending on the frequency, this measurement can vary by about 6db, thus
causing a higher reported channel noise and signal strength.

Factor in the 6db offset when converting internal noisefloor to channel noise.

This patch makes the reported values more accurate for all chips without
affecting NF calibration behavior.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
firewire: net: Fix handling of fragmented multicast/broadcast packets.

commit 9d2373420900a39f5212a3b289331aa3535b1000 upstream.

This patch fixes both the transmit and receive portion of sending
fragmented mutlicast and broadcast packets.

The transmit section was broken because the offset for INTFRAG and
LASTFRAG packets were just miscalculated by IEEE1394_GASP_HDR_SIZE (which
was reserved with skb_push() in fwnet_send_packet).

The receive section was broken because in fwnet_incoming_packet is a call
to fwnet_peer_find_by_node_id(). Called with generation == -1 it will
not find a peer and the partial datagrams are associated to a peer.

[Stefan R:  The fix to use context->card->generation is not perfect.
It relies on the IR tasklet which processes packets from the prior bus
generation to run before the self-ID-complete worklet which sets the
current card generation.  Alas, there is no simple way of a race-free
implementation.  Let's do it this way for now.]

Signed-off-by: Stephan Gatzka <stephan.gatzka@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ASoC: sigmadsp: Fix endianness conversion issue

commit a3adb1432d7a3ad86bb17a1638e44414537e4118 upstream.

The 'addr' field of the sigma_action struct is stored as big endian in the
firmware file.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SCSI: mvsas: Fix oops when ata commond timeout.

commit 95ab000388974d8ffef8257306b4be6e8778b768 upstream.

Kernel message follows:

[  511.712011] sd 11:0:0:0: [sdf] command ffff8800a4e81400 timed out
[  511.712022] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
[  511.712024] sas: trying to find task 0xffff8800a4d24c80
[  511.712026] sas: sas_scsi_find_task: aborting task 0xffff8800a4d24c80
[  511.712029] drivers/scsi/mvsas/mv_sas.c 1631:mvs_abort_task()
mvi=ffff8800b5300000 task=ffff8800a4d24c80 slot=ffff8800b5325038
slot_idx=x0
[  511.712035] BUG: unable to handle kernel NULL pointer dereference at
0000000000000058
[  511.712040] IP: [<ffffffff815f8c0c>] _raw_spin_lock_irqsave+0xc/0x30
[  511.712047] PGD 0
[  511.712049] Oops: 0002 [#1] SMP
[  511.712052] Modules linked in: mvsas libsas scsi_transport_sas
raid456 async_pq async_xor xor async_memcpy async_raid6_recov raid6_pq
async_tx [last unloaded: mvsas]
[  511.712062] CPU 3
[  511.712066] Pid: 7322, comm: scsi_eh_11 Not tainted 3.5.0+ #106 To Be
Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M.
[  511.712068] RIP: 0010:[<ffffffff815f8c0c>]  [<ffffffff815f8c0c>]
_raw_spin_lock_irqsave+0xc/0x30
[  511.712073] RSP: 0018:ffff880098d3bcb0  EFLAGS: 00010086
[  511.712074] RAX: 0000000000000286 RBX: 0000000000000058 RCX:
00000000000000c3
[  511.712076] RDX: 0000000000000100 RSI: 0000000000000046 RDI:
0000000000000058
[  511.712078] RBP: ffff880098d3bcb0 R08: 000000000000000a R09:
0000000000000000
[  511.712080] R10: 00000000000004e8 R11: 00000000000004e7 R12:
ffff8800a4d24c80
[  511.712082] R13: 0000000000000050 R14: ffff8800b5325038 R15:
ffff8800a4eafe00
[  511.712084] FS:  0000000000000000(0000) GS:ffff8800bdb80000(0000)
knlGS:0000000000000000
[  511.712086] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  511.712088] CR2: 0000000000000058 CR3: 00000000a4ce6000 CR4:
00000000000407e0
[  511.712090] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[  511.712091] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
0000000000000400
[  511.712093] Process scsi_eh_11 (pid: 7322, threadinfo
ffff880098d3a000, task ffff8800a61dde40)
[  511.712095] Stack:
[  511.712096]  ffff880098d3bce0 ffffffff81060683 ffff880000000000
0000000000000000
[  511.712099]  ffff8800a4d24c80 ffff8800b5300000 ffff880098d3bcf0
ffffffffa0076a88
[  511.712102]  ffff880098d3bd50 ffffffffa0079bb5 ffff880000000000
ffff880000000018
[  511.712106] Call Trace:
[  511.712110]  [<ffffffff81060683>] complete+0x23/0x60
[  511.712115]  [<ffffffffa0076a88>] mvs_tmf_timedout+0x18/0x20 [mvsas]
[  511.712119]  [<ffffffffa0079bb5>] mvs_slot_complete+0x765/0x7d0
[mvsas]
[  511.712125]  [<ffffffffa005a17d>] sas_scsi_recover_host+0x55d/0xdb0
[libsas]
[  511.712128]  [<ffffffff8106d600>] ? idle_balance+0xe0/0x130
[  511.712133]  [<ffffffff813b150c>] scsi_error_handler+0xcc/0x470
[  511.712136]  [<ffffffff815f7ad0>] ? __schedule+0x370/0x730
[  511.712139]  [<ffffffff8105f728>] ? __wake_up_common+0x58/0x90
[  511.712142]  [<ffffffff813b1440>] ? scsi_eh_get_sense+0x110/0x110
[  511.712146]  [<ffffffff810571be>] kthread+0x8e/0xa0
[  511.712150]  [<ffffffff816015f4>] kernel_thread_helper+0x4/0x10
[  511.712153]  [<ffffffff81057130>] ? flush_kthread_work+0x120/0x120
[  511.712156]  [<ffffffff816015f0>] ? gs_change+0xb/0xb
[  511.712157] Code: 8a 00 01 00 00 89 d0 f0 66 0f b1 0f 66 39 d0 0f 94
c0 0f b6 c0 5d c3 0f 1f 84 00 00 00 00 00 55 48 89 e5 9c 58 fa ba 00 01
00 00 <f0> 66 0f c1 17 0f b6 ce 38 d1 74 11 0f 1f 84 00 00 00 00 00 f3
[  511.712191] RIP  [<ffffffff815f8c0c>] _raw_spin_lock_irqsave+0xc/0x30
[  511.712194]  RSP <ffff880098d3bcb0>
[  511.712196] CR2: 0000000000000058
[  511.712198] ---[ end trace a781c7b1e65db92c ]---

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Cc: CAI Qian <caiqian@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SCSI: mvsas: fix undefined bit shift

commit beecadea1b8d67f591b13f7099559f32f3fd601d upstream.

The macro bit(n) is defined as ((u32)1 << n), and thus it doesn't work
with n >= 32, such as in mvs_94xx_assign_reg_set():

	if (i >= 32) {
		mvi->sata_reg_set |= bit(i);
		...
	}

The shift ((u32)1 << n) with n >= 32 also leads to undefined behavior.
The result varies depending on the architecture.

This patch changes bit(n) to do a 64-bit shift.  It also simplifies
mv_ffc64() using __ffs64(), since invoking ffz() with ~0 is undefined.

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Acked-by: Xiangliang Yu <yuxiangl@marvell.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SCSI: prevent stack buffer overflow in host_reset

commit 072f19b4bea31cdd482d79f805413f2f9ac9e233 upstream.

store_host_reset() has tried to re-invent the wheel to compare sysfs strings.
Unfortunately it did so poorly and never bothered to check the input from
userspace before overwriting stack with it, so something simple as:

echo "WoopsieWoopsie" >
/sys/devices/pseudo_0/adapter0/host0/scsi_host/host0/host_reset

would result in:

[  316.310101] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff81f5bac7
[  316.310101]
[  316.320051] Pid: 6655, comm: sh Tainted: G        W    3.7.0-rc5-next-20121114-sasha-00016-g5c9d68d-dirty #129
[  316.320051] Call Trace:
[  316.340058] pps pps0: PPS event at 1352918752.620355751
[  316.340062] pps pps0: capture assert seq #303
[  316.320051]  [<ffffffff83b3856b>] panic+0xcd/0x1f4
[  316.320051]  [<ffffffff81f5bac7>] ? store_host_reset+0xd7/0x100
[  316.320051]  [<ffffffff8110b996>] __stack_chk_fail+0x16/0x20
[  316.320051]  [<ffffffff81f5bac7>] store_host_reset+0xd7/0x100
[  316.320051]  [<ffffffff81e55bb3>] dev_attr_store+0x13/0x30
[  316.320051]  [<ffffffff812f7db1>] sysfs_write_file+0x101/0x170
[  316.320051]  [<ffffffff8127acc8>] vfs_write+0xb8/0x180
[  316.320051]  [<ffffffff8127ae80>] sys_write+0x50/0xa0
[  316.320051]  [<ffffffff83c03418>] tracesys+0xe1/0xe6

Fix this by uninventing whatever was going on there and just use sysfs_streq.

Bug introduced by 29443691 ("[SCSI] scsi: Added support for adapter and
firmware reset").

[jejb: added necessary const to prevent compile warnings]
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SCSI: qla2xxx: Test and clear FCPORT_UPDATE_NEEDED atomically.

commit a394aac88506159e047630fc90dc2242568382d8 upstream.

When the qla2xxx driver loses access to multiple, remote ports, there is a race
condition which can occur which will keep the request stuck on a scsi request
queue indefinitely.

This bad state occurred do to a race condition with how the FCPORT_UPDATE_NEEDED
bit is set in qla2x00_schedule_rport_del(), and how it is cleared in
qla2x00_do_dpc().  The problem port has its drport pointer set, but it has never
been processed by the driver to inform the fc transport that the port has been
lost.  qla2x00_schedule_rport_del() sets drport, and then sets the
FCPORT_UPDATE_NEEDED bit.  In qla2x00_do_dpc(), the port lists are walked and
any drport pointer is handled and the fc transport informed of the port loss,
then the FCPORT_UPDATE_NEEDED bit is cleared.  This leaves a race where the
dpc thread is processing one port removal, another port removal is marked
with a call to qla2x00_schedule_rport_del(), and the dpc thread clears the
bit for both removals, even though only the first removal was actually
handled.  Until another event occurs to set FCPORT_UPDATE_NEEDED, the later
port removal is never finished and qla2xxx stays in a bad state which causes
requests to become stuck on request queues.

This patch updates the driver to test and clear FCPORT_UPDATE_NEEDED
atomically.  This ensures the port state changes are processed and not lost.

Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>