From 8e0d1edb5c16732b695eaf4bd7096b1569817cf0 Mon Sep 17 00:00:00 2001 From: Yang Wang Date: Thu, 24 Jul 2025 15:16:18 +0800 Subject: [PATCH 4509/5403] drm/amd/amdgpu: fix missing lock for cper.ring->rptr/wptr access Add lock protection for 'ring->wptr'/'ring->rptr' to ensure the correct execution. Fixes: 8652920d2c00 ("drm/amdgpu: add mutex lock for cper ring") Signed-off-by: Yang Wang Reviewed-by: Tao Zhou Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_cper.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cper.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cper.c index 15dde1f50328..25252231a68a 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cper.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cper.c @@ -459,7 +459,7 @@ static u32 amdgpu_cper_ring_get_ent_sz(struct amdgpu_ring *ring, u64 pos) void amdgpu_cper_ring_write(struct amdgpu_ring *ring, void *src, int count) { - u64 pos, wptr_old, rptr = *ring->rptr_cpu_addr & ring->ptr_mask; + u64 pos, wptr_old, rptr; int rec_cnt_dw = count >> 2; u32 chunk, ent_sz; u8 *s = (u8 *)src; @@ -472,9 +472,11 @@ void amdgpu_cper_ring_write(struct amdgpu_ring *ring, void *src, int count) return; } + mutex_lock(&ring->adev->cper.ring_lock); + wptr_old = ring->wptr; + rptr = *ring->rptr_cpu_addr & ring->ptr_mask; - mutex_lock(&ring->adev->cper.ring_lock); while (count) { ent_sz = amdgpu_cper_ring_get_ent_sz(ring, ring->wptr); chunk = umin(ent_sz, count); -- 2.54.0