From: Lucas Stach l.stach@pengutronix.de
commit e168c25526cd0368af098095c2ded4a008007e1b upstream.
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 Tested-by: Guido Günther agx@sigxcpu.org Acked-by: Guido Günther agx@sigxcpu.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/etnaviv/etnaviv_mmu.c | 6 ++++++ 1 file changed, 6 insertions(+)
--- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c @@ -282,6 +282,12 @@ void etnaviv_iommu_unmap_gem(struct etna
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);