| Message ID | 20170531000546.30762-1-michel.thierry@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 30/05/17 17:05, Michel Thierry wrote: > We are passing parameters in the wrong order to find next zero bit, and > when it doesn't find anything it returns size (offset in the code), which > is always zero. > > For reference the function is defined as: > find_next_bit( *addr, size, offset ) > > The incorrect parameter order was added by commit abddffdf3620e > ("drm/i915/guc: Sanitize GuC client initialization"). Luckily, currently > we only use a single guc client and a single doorbell, which happens to be > zero; therefore it isn't necessary to backport this fix (which would be for > v4.12). > > Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > Cc: Oscar Mateo <oscar.mateo@intel.com> > Signed-off-by: Michel Thierry <michel.thierry@intel.com> > --- Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Thanks, Daniele > drivers/gpu/drm/i915/i915_guc_submission.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c > index fb936bb5cb93..ec391ef981aa 100644 > --- a/drivers/gpu/drm/i915/i915_guc_submission.c > +++ b/drivers/gpu/drm/i915/i915_guc_submission.c > @@ -105,7 +105,7 @@ static int __reserve_doorbell(struct i915_guc_client *client) > end += offset; > } > > - id = find_next_zero_bit(client->guc->doorbell_bitmap, offset, end); > + id = find_next_zero_bit(client->guc->doorbell_bitmap, end, offset); > if (id == end) > return -ENOSPC; > >
On ti, 2017-05-30 at 17:19 -0700, Daniele Ceraolo Spurio wrote: > > On 30/05/17 17:05, Michel Thierry wrote: > > > > We are passing parameters in the wrong order to find next zero bit, and > > when it doesn't find anything it returns size (offset in the code), which > > is always zero. > > > > For reference the function is defined as: > > find_next_bit( *addr, size, offset ) > > > > The incorrect parameter order was added by commit abddffdf3620e > > ("drm/i915/guc: Sanitize GuC client initialization"). Luckily, currently > > we only use a single guc client and a single doorbell, which happens to be > > zero; therefore it isn't necessary to backport this fix (which would be for > > v4.12). Whoops, a good catch. Regards, Joonas
On ke, 2017-05-31 at 00:21 +0000, Patchwork wrote: > == Series Details == > > Series: drm/i915/guc: Fix doorbell id selection > URL : https://patchwork.freedesktop.org/series/25076/ > State : success Merged. Thanks for the patch and review. Regards, Joonas
diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c index fb936bb5cb93..ec391ef981aa 100644 --- a/drivers/gpu/drm/i915/i915_guc_submission.c +++ b/drivers/gpu/drm/i915/i915_guc_submission.c @@ -105,7 +105,7 @@ static int __reserve_doorbell(struct i915_guc_client *client) end += offset; } - id = find_next_zero_bit(client->guc->doorbell_bitmap, offset, end); + id = find_next_zero_bit(client->guc->doorbell_bitmap, end, offset); if (id == end) return -ENOSPC;
We are passing parameters in the wrong order to find next zero bit, and when it doesn't find anything it returns size (offset in the code), which is always zero. For reference the function is defined as: find_next_bit( *addr, size, offset ) The incorrect parameter order was added by commit abddffdf3620e ("drm/i915/guc: Sanitize GuC client initialization"). Luckily, currently we only use a single guc client and a single doorbell, which happens to be zero; therefore it isn't necessary to backport this fix (which would be for v4.12). Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Oscar Mateo <oscar.mateo@intel.com> Signed-off-by: Michel Thierry <michel.thierry@intel.com> --- drivers/gpu/drm/i915/i915_guc_submission.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)