[ 019/128] drm/i915; Only increment the user-pin-count after successfully pinning the bo

Ben Hutchings
2013-02-03T15:23:45Z

From: Chris Wilson <chris@chris-wilson.co.uk>

commit 93be8788e648817d62fda33e2998eb6ca6ebf3a3 upstream.

As along the error path we do not correct the user pin-count for the
failure, we may end up with userspace believing that it has a pinned
object at offset 0 (when interrupted by a signal for example).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/gpu/drm/i915/i915_gem.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3456,14 +3456,15 @@ i915_gem_pin_ioctl(struct drm_device *de
goto out;
}

- obj->user_pin_count++;
- obj->pin_filp = file;
- if (obj->user_pin_count == 1) {
+ if (obj->user_pin_count == 0) {
ret = i915_gem_object_pin(obj, args->alignment, true);
if (ret)
goto out;
}

+ obj->user_pin_count++;
+ obj->pin_filp = file;
+
/* XXX - flush the CPU caches for pinned objects
* as the X server doesn't manage domains yet
*/