| Message ID | 20220323160825.3858619-1-l.stach@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/4] drm/etnaviv: check for reaped mapping in etnaviv_iommu_unmap_gem | expand |
On Mi, 2022-03-23 at 17:08 +0100, Lucas Stach wrote: > When the mapping is already reaped the unmap must be a no-op, as we > would otherwise try to remove the mapping twice, corrupting the > involved > data structures. > > Cc: stable@vger.kernel.org # 5.4 > Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> regards Philipp
Hi Lucas, On Wed, Mar 23, 2022 at 05:08:22PM +0100, Lucas Stach wrote: > When the mapping is already reaped the unmap must be a no-op, as we > would otherwise try to remove the mapping twice, corrupting the involved > data structures. > > Cc: stable@vger.kernel.org # 5.4 > Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Whole series Tested-by: Guido Günther <agx@sigxcpu.org> Acked-by: Guido Günther <agx@sigxcpu.org> The code changes look good to me too but I got some details wrong too many times for a `Reviewed-by:` Cheers, -- Guido > --- > drivers/gpu/drm/etnaviv/etnaviv_mmu.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c > index 9fb1a2aadbcb..aabb997a74eb 100644 > --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c > +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c > @@ -286,6 +286,12 @@ void etnaviv_iommu_unmap_gem(struct etnaviv_iommu_context *context, > > mutex_lock(&context->lock); > > + /* Bail if the mapping has been reaped by another thread */ > + if (!mapping->context) { > + mutex_unlock(&context->lock); > + return; > + } > + > /* If the vram node is on the mm, unmap and remove the node */ > if (mapping->vram_node.mm == &context->mm) > etnaviv_iommu_remove_mapping(context, mapping); > -- > 2.30.2 >
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c index 9fb1a2aadbcb..aabb997a74eb 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c @@ -286,6 +286,12 @@ void etnaviv_iommu_unmap_gem(struct etnaviv_iommu_context *context, mutex_lock(&context->lock); + /* Bail if the mapping has been reaped by another thread */ + if (!mapping->context) { + mutex_unlock(&context->lock); + return; + } + /* If the vram node is on the mm, unmap and remove the node */ if (mapping->vram_node.mm == &context->mm) etnaviv_iommu_remove_mapping(context, mapping);
When the mapping is already reaped the unmap must be a no-op, as we would otherwise try to remove the mapping twice, corrupting the involved data structures. Cc: stable@vger.kernel.org # 5.4 Signed-off-by: Lucas Stach <l.stach@pengutronix.de> --- drivers/gpu/drm/etnaviv/etnaviv_mmu.c | 6 ++++++ 1 file changed, 6 insertions(+)