a3aab894d9
[ Upstream commit d71ba1649fa3c464c51ec7163e4b817345bff2c7 ] kthread_mod_delayed_work() might race with kthread_cancel_delayed_work_sync() or another kthread_mod_delayed_work() call. The function lets the other operation win when it sees work->canceling counter set. And it returns @false. But it should return @true as it is done by the related workqueue API, see mod_delayed_work_on(). The reason is that the return value might be used for reference counting. It has to distinguish the case when the number of queued works has changed or stayed the same. The change is safe. kthread_mod_delayed_work() return value is not checked anywhere at the moment. Link: https://lore.kernel.org/r/20210521163526.GA17916@redhat.com Link: https://lkml.kernel.org/r/20210610133051.15337-4-pmladek@suse.com Signed-off-by: Petr Mladek <pmladek@suse.com> Reported-by: Oleg Nesterov <oleg@redhat.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Minchan Kim <minchan@google.com> Cc: <jenhaochen@google.com> Cc: Martin Liu <liumartin@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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.