e14177f197
Since commit e5dadff4b093 ("drm/i915: Protect request retirement with
timeline->mutex"), the request retirement can happen outside of the
struct_mutex serialised only by the timeline->mutex. We drop the
timeline->mutex on submitting the request (i915_request_add) so after
that point, it is liable to be freed. Make sure our local reference is
kept alive until we have finished attaching it to the signalers. (Note
that this erodes the argument that i915_request_add should consume the
reference, but that is a slightly larger patch!)
Fixes: e5dadff4b093 ("drm/i915: Protect request retirement with timeline->mutex")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191217134729.3297818-1-chris@chris-wilson.co.uk
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.