| Message ID | 1406101678-2111-1-git-send-email-deathsimple@vodafone.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 23.07.2014 16:47, Christian König wrote: > From: Christian König <christian.koenig@amd.com> > > We must mask out the overflow bit as well, otherwise > the wptr will never match the rptr again and the interrupt > handler will loop forever. > > Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Michel Dänzer <michel.daenzer@amd.com> > Cc: stable@vger.kernel.org Not sure this is justified though. Were you able to reproduce the problem and verify the fix?
Am 23.07.2014 11:07, schrieb Michel Dänzer: > On 23.07.2014 16:47, Christian König wrote: >> From: Christian König <christian.koenig@amd.com> >> >> We must mask out the overflow bit as well, otherwise >> the wptr will never match the rptr again and the interrupt >> handler will loop forever. >> >> Signed-off-by: Christian König <christian.koenig@amd.com> > Reviewed-by: Michel Dänzer <michel.daenzer@amd.com> > > >> Cc: stable@vger.kernel.org > Not sure this is justified though. Were you able to reproduce the > problem and verify the fix? Not yet, reproducing ring buffer overflows aren't easy to do. But I've had that multiple times with CIK and userptr support work and I can try if I can reproduce it once more. From reading the code it looks like a rather fundamental problem to me and because of this I've added the stable Cc. Christian.
On Wed, Jul 23, 2014 at 3:47 AM, Christian König <deathsimple@vodafone.de> wrote: > From: Christian König <christian.koenig@amd.com> > > We must mask out the overflow bit as well, otherwise > the wptr will never match the rptr again and the interrupt > handler will loop forever. > > Signed-off-by: Christian König <christian.koenig@amd.com> > Cc: stable@vger.kernel.org Applied to my 3.16 tree. Thanks! Alex > --- > drivers/gpu/drm/radeon/cik.c | 1 + > drivers/gpu/drm/radeon/evergreen.c | 1 + > drivers/gpu/drm/radeon/r600.c | 1 + > drivers/gpu/drm/radeon/si.c | 1 + > 4 files changed, 4 insertions(+) > > diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c > index 0b24711..cc1f02f 100644 > --- a/drivers/gpu/drm/radeon/cik.c > +++ b/drivers/gpu/drm/radeon/cik.c > @@ -7376,6 +7376,7 @@ static inline u32 cik_get_ih_wptr(struct radeon_device *rdev) > tmp = RREG32(IH_RB_CNTL); > tmp |= IH_WPTR_OVERFLOW_CLEAR; > WREG32(IH_RB_CNTL, tmp); > + wptr &= ~RB_OVERFLOW; > } > return (wptr & rdev->ih.ptr_mask); > } > diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c > index 250bac3..15e4f28 100644 > --- a/drivers/gpu/drm/radeon/evergreen.c > +++ b/drivers/gpu/drm/radeon/evergreen.c > @@ -4756,6 +4756,7 @@ static u32 evergreen_get_ih_wptr(struct radeon_device *rdev) > tmp = RREG32(IH_RB_CNTL); > tmp |= IH_WPTR_OVERFLOW_CLEAR; > WREG32(IH_RB_CNTL, tmp); > + wptr &= ~RB_OVERFLOW; > } > return (wptr & rdev->ih.ptr_mask); > } > diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c > index c66952d..3c69f58 100644 > --- a/drivers/gpu/drm/radeon/r600.c > +++ b/drivers/gpu/drm/radeon/r600.c > @@ -3795,6 +3795,7 @@ static u32 r600_get_ih_wptr(struct radeon_device *rdev) > tmp = RREG32(IH_RB_CNTL); > tmp |= IH_WPTR_OVERFLOW_CLEAR; > WREG32(IH_RB_CNTL, tmp); > + wptr &= ~RB_OVERFLOW; > } > return (wptr & rdev->ih.ptr_mask); > } > diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c > index eba0225..9e854fd 100644 > --- a/drivers/gpu/drm/radeon/si.c > +++ b/drivers/gpu/drm/radeon/si.c > @@ -6103,6 +6103,7 @@ static inline u32 si_get_ih_wptr(struct radeon_device *rdev) > tmp = RREG32(IH_RB_CNTL); > tmp |= IH_WPTR_OVERFLOW_CLEAR; > WREG32(IH_RB_CNTL, tmp); > + wptr &= ~RB_OVERFLOW; > } > return (wptr & rdev->ih.ptr_mask); > } > -- > 1.9.1 >
diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c index 0b24711..cc1f02f 100644 --- a/drivers/gpu/drm/radeon/cik.c +++ b/drivers/gpu/drm/radeon/cik.c @@ -7376,6 +7376,7 @@ static inline u32 cik_get_ih_wptr(struct radeon_device *rdev) tmp = RREG32(IH_RB_CNTL); tmp |= IH_WPTR_OVERFLOW_CLEAR; WREG32(IH_RB_CNTL, tmp); + wptr &= ~RB_OVERFLOW; } return (wptr & rdev->ih.ptr_mask); } diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c index 250bac3..15e4f28 100644 --- a/drivers/gpu/drm/radeon/evergreen.c +++ b/drivers/gpu/drm/radeon/evergreen.c @@ -4756,6 +4756,7 @@ static u32 evergreen_get_ih_wptr(struct radeon_device *rdev) tmp = RREG32(IH_RB_CNTL); tmp |= IH_WPTR_OVERFLOW_CLEAR; WREG32(IH_RB_CNTL, tmp); + wptr &= ~RB_OVERFLOW; } return (wptr & rdev->ih.ptr_mask); } diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c index c66952d..3c69f58 100644 --- a/drivers/gpu/drm/radeon/r600.c +++ b/drivers/gpu/drm/radeon/r600.c @@ -3795,6 +3795,7 @@ static u32 r600_get_ih_wptr(struct radeon_device *rdev) tmp = RREG32(IH_RB_CNTL); tmp |= IH_WPTR_OVERFLOW_CLEAR; WREG32(IH_RB_CNTL, tmp); + wptr &= ~RB_OVERFLOW; } return (wptr & rdev->ih.ptr_mask); } diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c index eba0225..9e854fd 100644 --- a/drivers/gpu/drm/radeon/si.c +++ b/drivers/gpu/drm/radeon/si.c @@ -6103,6 +6103,7 @@ static inline u32 si_get_ih_wptr(struct radeon_device *rdev) tmp = RREG32(IH_RB_CNTL); tmp |= IH_WPTR_OVERFLOW_CLEAR; WREG32(IH_RB_CNTL, tmp); + wptr &= ~RB_OVERFLOW; } return (wptr & rdev->ih.ptr_mask); }