]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
drm/i915: Prevent a race during I915_GEM_MMAP ioctl with WC set
authorJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Thu, 7 Feb 2019 08:54:53 +0000 (10:54 +0200)
committerJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Thu, 7 Feb 2019 12:10:35 +0000 (14:10 +0200)
commit5c4604e757ba9b193b09768d75a7d2105a5b883f
tree8d3109a412a8bb23a5b53be76d5ba079f296952f
parent6cbb55c086b4f23ad100f34cdeab496c4e99e0a6
drm/i915: Prevent a race during I915_GEM_MMAP ioctl with WC set

Make sure the underlying VMA in the process address space is the
same as it was during vm_mmap to avoid applying WC to wrong VMA.

A more long-term solution would be to have vm_mmap_locked variant
in linux/mmap.h for when caller wants to hold mmap_sem for an
extended duration.

v2:
- Refactor the compare function

Fixes: 1816f9236303 ("drm/i915: Support creation of unbound wc user mappings for objects")
Reported-by: Adam Zabrocki <adamza@microsoft.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: <stable@vger.kernel.org> # v4.0+
Cc: Akash Goel <akash.goel@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Adam Zabrocki <adamza@microsoft.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20190207085454.10598-1-joonas.lahtinen@linux.intel.com
drivers/gpu/drm/i915/i915_gem.c