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Quinn Tran 3a4b6cc733 scsi: qla2xxx: Fix premature timer expiration
For any qla2xxx async command, the SRB buffer is used to send it. In
setting up the SRB buffer, the timer for this command is started before all
memory allocation has finished.  Under low memory pressure, memory alloc
can go to sleep and not wake up before the timer expires. Once timer has
expired, the timer thread will access uninitialize fields resulting into
NULL pointer crash.

This patch fixes this crash by moving the start of timer after everything
is setup.

backtrace shows following

PID: 3720   TASK: ffff996928401040  CPU: 0   COMMAND: "qla2xxx_1_dpc"
0 [ffff99652751b698] __schedule at ffffffff965676c7
1 [ffff99652751b728] schedule at ffffffff96567bc9
2 [ffff99652751b738] schedule_timeout at ffffffff965655e8
3 [ffff99652751b7e0] io_schedule_timeout at ffffffff9656726d
4 [ffff99652751b810] congestion_wait at ffffffff95fd8d12
5 [ffff99652751b870] isolate_migratepages_range at ffffffff95fddaf3
6 [ffff99652751b930] compact_zone at ffffffff95fdde96
7 [ffff99652751b980] compact_zone_order at ffffffff95fde0bc
8 [ffff99652751ba20] try_to_compact_pages at ffffffff95fde481
9 [ffff99652751ba80] __alloc_pages_direct_compact at ffffffff9655cc31
10 [ffff99652751bae0] __alloc_pages_slowpath at ffffffff9655d101
11 [ffff99652751bbd0] __alloc_pages_nodemask at ffffffff95fc0e95
12 [ffff99652751bc80] dma_generic_alloc_coherent at ffffffff95e3217f
13 [ffff99652751bcc8] x86_swiotlb_alloc_coherent at ffffffff95e6b7a1
14 [ffff99652751bcf8] qla2x00_rft_id at ffffffffc055b5e0 [qla2xxx]
15 [ffff99652751bd50] qla2x00_loop_resync at ffffffffc0533e71 [qla2xxx]
16 [ffff99652751be68] qla2x00_do_dpc at ffffffffc05210ca [qla2xxx]

PID: 0      TASK: ffffffff96a18480  CPU: 0   COMMAND: "swapper/0"
 0 [ffff99652fc03ae0] machine_kexec at ffffffff95e63674
 1 [ffff99652fc03b40] __crash_kexec at ffffffff95f1ce12
 2 [ffff99652fc03c10] crash_kexec at ffffffff95f1cf00
 3 [ffff99652fc03c28] oops_end at ffffffff9656c758
 4 [ffff99652fc03c50] no_context at ffffffff9655aa7e
 5 [ffff99652fc03ca0] __bad_area_nosemaphore at ffffffff9655ab15
 6 [ffff99652fc03cf0] bad_area_nosemaphore at ffffffff9655ac86
 7 [ffff99652fc03d00] __do_page_fault at ffffffff9656f6b0
 8 [ffff99652fc03d70] do_page_fault at ffffffff9656f915
 9 [ffff99652fc03da0] page_fault at ffffffff9656b758
    [exception RIP: unknown or invalid address]
    RIP: 0000000000000000  RSP: ffff99652fc03e50  RFLAGS: 00010202
    RAX: 0000000000000000  RBX: ffff99652b79a600  RCX: ffff99652b79a760
    RDX: ffff99652b79a600  RSI: ffffffffc0525ad0  RDI: ffff99652b79a600
    RBP: ffff99652fc03e60   R8: ffffffff96a18a18   R9: ffffffff96ee3c00
    R10: 0000000000000002  R11: ffff99652fc03de8  R12: ffff99652b79a760
    R13: 0000000000000100  R14: ffffffffc0525ad0  R15: ffff99652b79a600
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
10 [ffff99652fc03e50] qla2x00_sp_timeout at ffffffffc0525af8 [qla2xxx]
11 [ffff99652fc03e68] call_timer_fn at ffffffff95ea7f58
12 [ffff99652fc03ea0] run_timer_softirq at ffffffff95eaa3bd
13 [ffff99652fc03f18] __do_softirq at ffffffff95ea0f05
14 [ffff99652fc03f88] call_softirq at ffffffff9657832c
15 [ffff99652fc03fa0] do_softirq at ffffffff95e2e675
16 [ffff99652fc03fc0] irq_exit at ffffffff95ea1285
17 [ffff99652fc03fd8] smp_apic_timer_interrupt at ffffffff965796c8
18 [ffff99652fc03ff0] apic_timer_interrupt at ffffffff96575df2

Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-08-07 18:08:12 -04:00
arch hexagon: switch to generic version of pte allocation 2019-07-21 09:53:00 -07:00
block docs conversion for v5.3-rc1 2019-07-16 12:21:41 -07:00
certs Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs" 2019-07-10 18:43:43 -07:00
crypto USB / PHY patches for 5.3-rc1 2019-07-11 15:40:06 -07:00
Documentation Devicetree fixes for 5.3: 2019-07-21 10:28:39 -07:00
drivers scsi: qla2xxx: Fix premature timer expiration 2019-08-07 18:08:12 -04:00
fs SMB3 fixes: two fixes for stable, one that had dependency on earlier patch in this merge window and can now go in, and a perf improvement in SMB3 open 2019-07-21 10:01:17 -07:00
include scsi: core: add support for request batching 2019-07-22 16:44:07 -04:00
init Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
ipc Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
kernel dma-mapping fixes for 5.3-rc1 2019-07-20 12:09:52 -07:00
lib Kbuild updates for v5.3 (2nd) 2019-07-20 09:34:55 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
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net Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-07-19 10:06:06 -07:00
scripts Kbuild updates for v5.3 (2nd) 2019-07-20 09:34:55 -07:00
security Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
sound sound fixes for 5.3-rc1 2019-07-18 09:36:51 -07:00
tools New feature to add support for NTB virtual MSI interrupts, the ability 2019-07-21 09:46:59 -07:00
usr Kbuild updates for v5.3 (2nd) 2019-07-20 09:34:55 -07:00
virt KVM: Boost vCPUs that are delivering interrupts 2019-07-20 09:00:45 +02:00
.clang-format Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-04-17 11:26:25 -07:00
.cocciconfig
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.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: create *.mod with full directory path and remove MODVERDIR 2019-07-18 02:19:31 +09:00
.mailmap MAINTAINERS: Update my email address 2019-06-18 14:37:27 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Remove references to dead website. 2019-07-19 12:22:04 -07:00
Kbuild Kbuild updates for v5.1 2019-03-10 17:48:21 -07:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-20 11:24:49 -07:00
Makefile Linus 5.3-rc1 2019-07-21 14:05:38 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.