From: Lucas Stach <l.stach@pengutronix.de> stable inclusion from stable-v5.10.121 commit 436cff507f2a41230baacc3e2ef1d3b2d2653f40 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6CQ Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- 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> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Acked-by: Xie XiuQi <xiexiuqi@huawei.com> --- 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 984569a59a90..9ba2fe48228f 100644 --- 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 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); -- 2.20.1