| Message ID | 20220630200405.1883897-2-dmitry.osipenko@collabora.com |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | DRM GEM fixes | expand |
On Thu, Jun 30, 2022 at 11:04:04PM +0300, Dmitry Osipenko wrote: > Use ww_acquire_fini() in the error code paths. Otherwise lockdep > thinks that lock is held when lock's memory is freed after the > drm_gem_lock_reservations() error. The ww_acquire_context needs to be > annotated as "released", which fixes the noisy "WARNING: held lock freed!" > splat of VirtIO-GPU driver with CONFIG_DEBUG_MUTEXES=y and enabled lockdep. > > Cc: stable@vger.kernel.org > Fixes: 7edc3e3b975b5 ("drm: Add helpers for locking an array of BO reservations.") > Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> > Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> I merged this one to drm-misc-next-fixes. The other one looks like there's still opens pending, pls resubmit appropriately (and maybe with some analysis in the commit message of how exactly this impacts other drivers). -Daniel > --- > drivers/gpu/drm/drm_gem.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c > index eb0c2d041f13..86d670c71286 100644 > --- a/drivers/gpu/drm/drm_gem.c > +++ b/drivers/gpu/drm/drm_gem.c > @@ -1226,7 +1226,7 @@ drm_gem_lock_reservations(struct drm_gem_object **objs, int count, > ret = dma_resv_lock_slow_interruptible(obj->resv, > acquire_ctx); > if (ret) { > - ww_acquire_done(acquire_ctx); > + ww_acquire_fini(acquire_ctx); > return ret; > } > } > @@ -1251,7 +1251,7 @@ drm_gem_lock_reservations(struct drm_gem_object **objs, int count, > goto retry; > } > > - ww_acquire_done(acquire_ctx); > + ww_acquire_fini(acquire_ctx); > return ret; > } > } > -- > 2.36.1 >
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index eb0c2d041f13..86d670c71286 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1226,7 +1226,7 @@ drm_gem_lock_reservations(struct drm_gem_object **objs, int count, ret = dma_resv_lock_slow_interruptible(obj->resv, acquire_ctx); if (ret) { - ww_acquire_done(acquire_ctx); + ww_acquire_fini(acquire_ctx); return ret; } } @@ -1251,7 +1251,7 @@ drm_gem_lock_reservations(struct drm_gem_object **objs, int count, goto retry; } - ww_acquire_done(acquire_ctx); + ww_acquire_fini(acquire_ctx); return ret; } }
Use ww_acquire_fini() in the error code paths. Otherwise lockdep thinks that lock is held when lock's memory is freed after the drm_gem_lock_reservations() error. The ww_acquire_context needs to be annotated as "released", which fixes the noisy "WARNING: held lock freed!" splat of VirtIO-GPU driver with CONFIG_DEBUG_MUTEXES=y and enabled lockdep. Cc: stable@vger.kernel.org Fixes: 7edc3e3b975b5 ("drm: Add helpers for locking an array of BO reservations.") Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> --- drivers/gpu/drm/drm_gem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)