drm/amdgpu: fix signed overrun in amdgpu_ctx_get_fence

Otherwise the first 16 fences of a context will always signal immediately.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
index 859a484..144edc9 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
@@ -226,7 +226,7 @@ struct fence *amdgpu_ctx_get_fence(struct amdgpu_ctx *ctx,
                return ERR_PTR(-EINVAL);
        }
 
-       if (seq < cring->sequence - AMDGPU_CTX_MAX_CS_PENDING) {
+       if (seq + AMDGPU_CTX_MAX_CS_PENDING < cring->sequence) {
                spin_unlock(&ctx->ring_lock);
                return NULL;
        }