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Saurabh Sengar d957e7ffb2 scsi: storvsc: Remove WQ_MEM_RECLAIM from storvsc_error_wq
storvsc_error_wq workqueue should not be marked as WQ_MEM_RECLAIM as it
doesn't need to make forward progress under memory pressure.  Marking this
workqueue as WQ_MEM_RECLAIM may cause deadlock while flushing a
non-WQ_MEM_RECLAIM workqueue.  In the current state it causes the following
warning:

[   14.506347] ------------[ cut here ]------------
[   14.506354] workqueue: WQ_MEM_RECLAIM storvsc_error_wq_0:storvsc_remove_lun is flushing !WQ_MEM_RECLAIM events_freezable_power_:disk_events_workfn
[   14.506360] WARNING: CPU: 0 PID: 8 at <-snip->kernel/workqueue.c:2623 check_flush_dependency+0xb5/0x130
[   14.506390] CPU: 0 PID: 8 Comm: kworker/u4:0 Not tainted 5.4.0-1086-azure #91~18.04.1-Ubuntu
[   14.506391] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022
[   14.506393] Workqueue: storvsc_error_wq_0 storvsc_remove_lun
[   14.506395] RIP: 0010:check_flush_dependency+0xb5/0x130
		<-snip->
[   14.506408] Call Trace:
[   14.506412]  __flush_work+0xf1/0x1c0
[   14.506414]  __cancel_work_timer+0x12f/0x1b0
[   14.506417]  ? kernfs_put+0xf0/0x190
[   14.506418]  cancel_delayed_work_sync+0x13/0x20
[   14.506420]  disk_block_events+0x78/0x80
[   14.506421]  del_gendisk+0x3d/0x2f0
[   14.506423]  sr_remove+0x28/0x70
[   14.506427]  device_release_driver_internal+0xef/0x1c0
[   14.506428]  device_release_driver+0x12/0x20
[   14.506429]  bus_remove_device+0xe1/0x150
[   14.506431]  device_del+0x167/0x380
[   14.506432]  __scsi_remove_device+0x11d/0x150
[   14.506433]  scsi_remove_device+0x26/0x40
[   14.506434]  storvsc_remove_lun+0x40/0x60
[   14.506436]  process_one_work+0x209/0x400
[   14.506437]  worker_thread+0x34/0x400
[   14.506439]  kthread+0x121/0x140
[   14.506440]  ? process_one_work+0x400/0x400
[   14.506441]  ? kthread_park+0x90/0x90
[   14.506443]  ret_from_fork+0x35/0x40
[   14.506445] ---[ end trace 2d9633159fdc6ee7 ]---

Link: https://lore.kernel.org/r/1659628534-17539-1-git-send-email-ssengar@linux.microsoft.com
Fixes: 436ad94133 ("scsi: storvsc: Allow only one remove lun work item to be issued per lun")
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-08-11 22:25:23 -04:00
Documentation scsi: ufs: dt-bindings: Add SC8280XP binding 2022-07-26 22:13:28 -04:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
arch Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
block scsi: core: bsg: Remove usage of the deprecated ida_simple_xxx() API 2022-06-21 21:22:51 -04:00
certs Kbuild updates for v5.19 2022-05-26 12:09:50 -07:00
crypto This update includes the following changes: 2022-05-27 18:06:49 -07:00
drivers scsi: storvsc: Remove WQ_MEM_RECLAIM from storvsc_error_wq 2022-08-11 22:25:23 -04:00
fs fix for breakage in #work.fd this window 2022-06-05 17:14:03 -07:00
include scsi: ufs: core: Enable link lost interrupt 2022-08-11 22:04:32 -04:00
init This set of changes updates init and user mode helper tasks to be 2022-06-03 16:03:05 -07:00
ipc These changes update the ipc sysctls so that they are fundamentally 2022-06-03 15:54:57 -07:00
kernel A single featurelet for delay accounting. Delayed a bit 2022-06-05 16:58:27 -07:00
lib Bitmap patches for 5.19-rc1 2022-06-04 14:04:27 -07:00
mm Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
net bluetooth: don't use bitmaps for random flag accesses 2022-06-05 16:28:41 -07:00
samples drm for 5.19-rc1 2022-05-25 16:18:27 -07:00
scripts A set of objtool fixes: 2022-06-05 09:45:27 -07:00
security Cleanups (and one fix) around struct mount handling. 2022-06-04 19:00:05 -07:00
sound USB / Thunderbolt changes for 5.19-rc1 2022-06-03 11:17:49 -07:00
tools A single featurelet for delay accounting. Delayed a bit 2022-06-05 16:58:27 -07:00
usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt VFIO updates for v5.19-rc1 2022-06-01 13:49:15 -07:00
.clang-format clang-format: Fix space after for_each macros 2022-05-20 19:27:16 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: split the second line of *.mod into *.usyms 2022-05-08 03:16:59 +09:00
.mailmap Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS scsi: dpt_i2o: Remove obsolete driver 2022-06-27 22:56:21 -04:00
Makefile Linux 5.19-rc1 2022-06-05 17:18:54 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

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.