From d7b1eeb2ca039d04f1a1fcb241920cb112b4b52a Mon Sep 17 00:00:00 2001 From: Monk Liu Date: Fri, 7 Apr 2017 18:39:07 +0800 Subject: [PATCH] drm/amdgpu:fix race condition MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit sequence is protected by spinlock so don't access sequence in paramter seq when invoking this function. ~0 means to get the latest sequence number and 0 means none to get. Change-Id: Ib7a03f3cf5594deeb4ad333cc59b47a6bddfd1ad Signed-off-by: Monk Liu Reviewed-by: Christian König Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c | 3 +++ include/uapi/drm/amdgpu_drm.h | 5 ++++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c index cf0500671353..90d1ac8a80f8 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c @@ -273,6 +273,9 @@ struct dma_fence *amdgpu_ctx_get_fence(struct amdgpu_ctx *ctx, spin_lock(&ctx->ring_lock); + if (seq == ~0ull) + seq = ctx->rings[ring->idx].sequence - 1; + if (seq >= cring->sequence) { spin_unlock(&ctx->ring_lock); return ERR_PTR(-EINVAL); diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h index 516a9f285730..92262d81d41e 100644 --- a/include/uapi/drm/amdgpu_drm.h +++ b/include/uapi/drm/amdgpu_drm.h @@ -295,7 +295,10 @@ union drm_amdgpu_gem_wait_idle { }; struct drm_amdgpu_wait_cs_in { - /** Command submission handle */ + /* Command submission handle + * handle equals 0 means none to wait for + * handle equal ~0ull meanas wait for the latest sequence number + */ __u64 handle; /** Absolute timeout to wait */ __u64 timeout; -- 2.39.5