e3da6be3d7
Function gfs2_withdraw() tries to synchronize concurrent callers by atomically setting the SDF_WITHDRAWN flag in the first caller, setting the SDF_WITHDRAW_IN_PROG flag to indicate that a withdraw is in progress, performing the actual withdraw, and clearing the SDF_WITHDRAW_IN_PROG flag when done. All other callers wait for the SDF_WITHDRAW_IN_PROG flag to be cleared before returning. This leaves a small window in which callers can find the SDF_WITHDRAWN flag set before the SDF_WITHDRAW_IN_PROG flag has been set, causing them to return prematurely, before the withdraw has been completed. Fix that by setting the SDF_WITHDRAWN and SDF_WITHDRAW_IN_PROG flags atomically. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
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.