763766c057
Before this patch, if function gfs2_inode_lookup encountered an error
after it had locked the iopen glock, it never unlocked it, relying on
the evict code to do the cleanup. The evict code then took the
inode glock while holding the iopen glock, which violates the locking
order. For example,
(1) node A does a gfs2_inode_lookup that fails, leaving the iopen glock
locked.
(2) node B calls delete_work_func -> gfs2_lookup_by_inum ->
gfs2_inode_lookup. It locks the inode glock and blocks trying to
lock the iopen glock, which is held by node A.
(3) node A eventually calls gfs2_evict_inode -> evict_should_delete.
It blocks trying to lock the inode glock, which is now held by
node B.
This patch introduces error handling to function gfs2_inode_lookup
so it properly dequeues held iopen glocks on errors.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
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.