Go to file
Ioanna Alifieraki 1d49eb91e8 ipmi: Move remove_work to dedicated workqueue
Currently when removing an ipmi_user the removal is deferred as a work on
the system's workqueue. Although this guarantees the free operation will
occur in non atomic context, it can race with the ipmi_msghandler module
removal (see [1]) . In case a remove_user work is scheduled for removal
and shortly after ipmi_msghandler module is removed we can end up in a
situation where the module is removed fist and when the work is executed
the system crashes with :
BUG: unable to handle page fault for address: ffffffffc05c3450
PF: supervisor instruction fetch in kernel mode
PF: error_code(0x0010) - not-present page
because the pages of the module are gone. In cleanup_ipmi() there is no
easy way to detect if there are any pending works to flush them before
removing the module. This patch creates a separate workqueue and schedules
the remove_work works on it. When removing the module the workqueue is
drained when destroyed to avoid the race.

[1] https://bugs.launchpad.net/bugs/1950666

Cc: stable@vger.kernel.org # 5.1
Fixes: 3b9a907223 (ipmi: fix sleep-in-atomic in free_user at cleanup SRCU user->release_barrier)
Signed-off-by: Ioanna Alifieraki <ioanna-maria.alifieraki@canonical.com>
Message-Id: <20211115131645.25116-1-ioanna-maria.alifieraki@canonical.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
2021-11-15 08:45:14 -06:00
arch Merge branch 'akpm' (patches from Andrew) 2021-11-11 14:31:47 -08:00
block for-5.16/drivers-2021-11-09 2021-11-09 11:24:08 -08:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto Kbuild updates for v5.16 2021-11-08 09:15:45 -08:00
Documentation Merge branch 'akpm' (patches from Andrew) 2021-11-11 14:31:47 -08:00
drivers ipmi: Move remove_work to dedicated workqueue 2021-11-15 08:45:14 -06:00
fs Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
include pci-v5.16-fixes-1 2021-11-11 15:10:18 -08:00
init mm: allow only SLUB on PREEMPT_RT 2021-11-11 09:34:35 -08:00
ipc ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL 2021-11-09 10:02:53 -08:00
kernel KCSAN pull request for v5.16 2021-11-11 15:00:04 -08:00
lib mm/migrate.c: remove MIGRATE_PFN_LOCKED 2021-11-11 09:34:35 -08:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm Merge branch 'akpm' (patches from Andrew) 2021-11-11 14:31:47 -08:00
net Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
samples Add gitignore file for samples/fanotify/ subdirectory 2021-11-07 11:19:24 -08:00
scripts Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
security + Features 2021-11-11 14:47:32 -08:00
sound TTY / Serial driver update for 5.16-rc1 2021-11-04 09:09:37 -07:00
tools Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
usr initramfs: Check timestamp to prevent broken cpio archive 2021-10-24 13:48:40 +09:00
virt kvm: irqfd: avoid update unmodified entries of the routing 2021-09-30 04:27:10 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +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 .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
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 Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
Makefile Kbuild updates for v5.16 2021-11-08 09:15:45 -08:00
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.