2d3d22332b
wake_up_poll() uses nr_exclusive=1, so its not guaranteed to wake up
all exclusive waiters. Yet, POLLFREE *must* wake up all waiters. epoll
and aio poll are fortunately not affected by this, but its very
fragile. Thus, the new function wake_up_pollfree() has been introduced.
Convert signalfd to use wake_up_pollfree().
MTK-Commit-Id: dcf842d697ef618d3a7fc36b466016bd9b70183c
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: d80e731eca ("epoll: introduce POLLFREE to flush ->signalfd_wqh before kfree()")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211209010455.42744-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Light Hsieh <light.hsieh@mediatek.com>
CR-Id: ALPS06649447
Feature: Google Security Patch
Change-Id: I9b25a4974c6333cff47d1c74982f1167d11765e3
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.