From 415be17fb2f4a70afc827332c936955b801085ad Mon Sep 17 00:00:00 2001
From: "Jiadong.Zhu" <Jiadong.Zhu@amd.com>
Date: Thu, 15 Sep 2022 15:19:20 +0800
Subject: [PATCH] drm/amdgpu: Correct the position in patch_cond_exec
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The current position calulated in gfx_v9_0_ring_emit_patch_cond_exec
underflows when the wptr is divisible by ring->buf_mask + 1.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Jiadong.Zhu <Jiadong.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
index 34428e39649f..0320be4a5fc6 100644
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
@@ -5429,7 +5429,7 @@ static void gfx_v9_0_ring_emit_patch_cond_exec(struct amdgpu_ring *ring, unsigne
 	BUG_ON(offset > ring->buf_mask);
 	BUG_ON(ring->ring[offset] != 0x55aa55aa);
 
-	cur = (ring->wptr & ring->buf_mask) - 1;
+	cur = (ring->wptr - 1) & ring->buf_mask;
 	if (likely(cur > offset))
 		ring->ring[offset] = cur - offset;
 	else
-- 
2.30.9