From b7ca3f331d5777f0a997e4d3b58ca9248a263705 Mon Sep 17 00:00:00 2001 From: Lucas Stach Date: Tue, 21 May 2019 14:53:40 +0200 Subject: [PATCH] drm/etnaviv: lock MMU while dumping core [ Upstream commit 1396500d673bd027683a0609ff84dca7eb6ea2e7 ] The devcoredump needs to operate on a stable state of the MMU while it is writing the MMU state to the coredump. The missing lock allowed both the userspace submit, as well as the GPU job finish paths to mutate the MMU state while a coredump is under way. Fixes: a8c21a5451d8 (drm/etnaviv: add initial etnaviv DRM driver) Reported-by: David Jander Signed-off-by: Lucas Stach Tested-by: David Jander Reviewed-by: Philipp Zabel Signed-off-by: Sasha Levin --- drivers/gpu/drm/etnaviv/etnaviv_dump.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/etnaviv/etnaviv_dump.c b/drivers/gpu/drm/etnaviv/etnaviv_dump.c index 9146e30e24a6..468dff2f7904 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_dump.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_dump.c @@ -124,6 +124,8 @@ void etnaviv_core_dump(struct etnaviv_gpu *gpu) return; etnaviv_dump_core = false; + mutex_lock(&gpu->mmu->lock); + mmu_size = etnaviv_iommu_dump_size(gpu->mmu); /* We always dump registers, mmu, ring and end marker */ @@ -166,6 +168,7 @@ void etnaviv_core_dump(struct etnaviv_gpu *gpu) iter.start = __vmalloc(file_size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY, PAGE_KERNEL); if (!iter.start) { + mutex_unlock(&gpu->mmu->lock); dev_warn(gpu->dev, "failed to allocate devcoredump file\n"); return; } @@ -233,6 +236,8 @@ void etnaviv_core_dump(struct etnaviv_gpu *gpu) obj->base.size); } + mutex_unlock(&gpu->mmu->lock); + etnaviv_core_dump_header(&iter, ETDUMP_BUF_END, iter.data); dev_coredumpv(gpu->dev, iter.start, iter.data - iter.start, GFP_KERNEL); -- GitLab