mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-13 11:48:58 -04:00
2f588cee24
It seems like when ldsem_down_read() fails with timeout, it misses update for sem->wait_readers. By that reason, when writer finally releases write end of the semaphore __ldsem_wake_readers() does adjust sem->count with wrong value: sem->wait_readers * (LDSEM_ACTIVE_BIAS - LDSEM_WAIT_BIAS) I.e, if update comes with 1 missed wait_readers decrement, sem->count will be 0x100000001 which means that there is active reader and it'll make any further writer to fail in acquiring the semaphore. It looks like, this is a dead-code, because ldsem_down_read() is never called with timeout different than MAX_SCHEDULE_TIMEOUT, so it might be worth to delete timeout parameter and error path fall-back.. Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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.