diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2016-04-05 15:00:00 +0100 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2016-06-15 21:29:24 +0100 |
| commit | 646178dc82215c0314d7da4c7b60defdc9a9199a (patch) | |
| tree | 0c5e058dcab5302873c1cec81fcbfa6c0ffc9fa2 /include/linux | |
| parent | f5546371f95f5837ad300c3cafdb891814dee316 (diff) | |
drm/i915/userptr: Hold mmref whilst calling get-user-pages
commit db9f9203e27495b2d151b695504e286eec026e9b upstream.
Holding a reference to the containing task_struct is not sufficient to
prevent the mm_struct from being reaped under memory pressure. If this
happens whilst we are calling get_user_pages(), explosions erupt -
sometimes an immediate GPF, sometimes page flag corruption. To prevent
the target mm from being reaped as we are reading from it, acquire a
reference before we begin.
Testcase: igt/gem_shrink/*userptr
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1459864801-28606-2-git-send-email-chris@chris-wilson.co.uk
(cherry picked from commit 40313f0cd0b711a7a5905e5182422799e157d8aa)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
[bwh: Backported to 3.16:
- s/get_user_pages_remote/get_user_pages/
- s/npages/num_pages/]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'include/linux')
0 files changed, 0 insertions, 0 deletions