drm/i915: Don't destroy the vma placeholder during execbuffer reservation
authorChris Wilson <chris@chris-wilson.co.uk>
Tue, 20 Aug 2013 11:56:40 +0000 (12:56 +0100)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Wed, 4 Sep 2013 15:34:42 +0000 (17:34 +0200)
commitaaa0566792dc7ae68deb1959663581ea8c75d311
tree40befac8b2ba51f1f78367779f339ec15bae3da5
parente656a6cba0febf12a9838882b891e1c5917c7a8b
drm/i915: Don't destroy the vma placeholder during execbuffer reservation

The execbuffer handle and exec_link were moved from the object into the
vma. As the vma may be unbound and destroyed whilst attempting to
reserve the execbuffer objects (either through a forced unbind to fix up
a misalignment or through an evict-everything call) we need to prevent
the free of the i915_vma itself. Otherwise not only is the list of
objects to reserve corrupt, but we continue to reference stale vma
entries.

Fixes kernel crash with i-g-t/gem_evict_everything

This regression has been introduced in

commit 04038a515d6eda6dd0857c0ade0b3950d372f4c0
Author:     Ben Widawsky <ben@bwidawsk.net>
AuthorDate: Wed Aug 14 11:38:36 2013 +0200

    drm/i915: Convert execbuf code to use vmas

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
References: http://www.spinics.net/lists/intel-gfx/msg32038.html
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=68298
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drivers/gpu/drm/i915/i915_gem.c