From: Chris Wilson <chris at chris-wilson.co.uk>
As we recompute the remaining timeout after waiting, there is a
potential for that timeout to be less than zero and so need sanitizing.
The timeout is always returned to userspace and validated, so we should
always perform the sanitation.
v2 [vsyrjala]: Only normalize the timespec if it's invalid
v3: Add a comment to clarify the situation and remove the now
useless WARN_ON() (ickle)
Cc: Ben Widawsky <ben at bwidawsk.net>
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Ville Syrj?l? <ville.syrjala at linux.intel.com>
---
drivers/gpu/drm/i915/i915_gem.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 6be940e..6165535 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1045,6 +1045,8 @@ static int __wait_seqno(struct intel_ring_buffer *ring, u32 seqno,
if (timeout) {
struct timespec sleep_time = timespec_sub(now, before);
*timeout = timespec_sub(*timeout, sleep_time);
+ if (!timespec_valid(timeout)) /* i.e. negative time remains */
+ set_normalized_timespec(timeout, 0, 0);
}
switch (end) {
@@ -1053,8 +1055,6 @@ static int __wait_seqno(struct intel_ring_buffer *ring, u32 seqno,
case -ERESTARTSYS: /* Signal */
return (int)end;
case 0: /* Timeout */
- if (timeout)
- set_normalized_timespec(timeout, 0, 0);
return -ETIME;
default: /* Completed */
WARN_ON(end < 0); /* We're not aware of other errors */
@@ -2377,10 +2377,8 @@ i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
mutex_unlock(&dev->struct_mutex);
ret = __wait_seqno(ring, seqno, reset_counter, true, timeout);
- if (timeout) {
- WARN_ON(!timespec_valid(timeout));
+ if (timeout)
args->timeout_ns = timespec_to_ns(timeout);
- }
return ret;
out:
--
1.8.1.5
