On Tue, Apr 09, 2013 at 10:13:23AM +0100, Chris Wilson wrote:
> 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.
>
> Cc: Ville Syrj?l? <ville.syrjala at linux.intel.com>
> Cc: Ben Widawsky <ben at bwidawsk.net>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
> drivers/gpu/drm/i915/i915_gem.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 63c05dd..fcf8492 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -1045,6 +1045,7 @@ 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);
> + set_normalized_timespec(timeout, 0, 0);
This will just set timeout = {0,0}, no?
And timespec_sub() should already return a normalized timespec, so I
guess the warning would just trigger when sleep_time > timeout. So we
should maybe just check for that case, and only then set timeout={0,0}?
> }
>
> switch (end) {
> @@ -1053,8 +1054,6 @@ 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 */
> --
> 1.7.10.4
--
Ville Syrj?l?
Intel OTC
