On 8/15/22 20:15, Dong, Ruijing wrote:
[AMD Official Use Only - General]
Sorry, which "r" value was overwritten? I didn't see the point of making this change.
Thanks
Ruijing
-----Original Message-----
From: Khalid Masum <khalid.masum.92@xxxxxxxxx>
Sent: Monday, August 15, 2022 3:01 AM
To: amd-gfx@xxxxxxxxxxxxxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-kernel-mentees@xxxxxxxxxxxxxxxxxxxxxxxxx
Cc: Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Koenig, Christian <Christian.Koenig@xxxxxxx>; Pan, Xinhui <Xinhui.Pan@xxxxxxx>; David Airlie <airlied@xxxxxxxx>; Daniel Vetter <daniel@xxxxxxxx>; Zhu, James <James.Zhu@xxxxxxx>; Jiang, Sonny <Sonny.Jiang@xxxxxxx>; Dong, Ruijing <Ruijing.Dong@xxxxxxx>; Wan Jiabing <wanjiabing@xxxxxxxx>; Liu, Leo <Leo.Liu@xxxxxxx>; Khalid Masum <khalid.masum.92@xxxxxxxxx>
Subject: [PATCH linux-next] drm/amdgpu/vcn: Remove unused assignment in vcn_v4_0_stop
The value assigned from vcn_v4_0_stop_dbg_mode to r is overwritten before it can be used. Remove this assignment.
Addresses-Coverity: 1504988 ("Unused value")
Fixes: 8da1170a16e4 ("drm/amdgpu: add VCN4 ip block support")
Signed-off-by: Khalid Masum <khalid.masum.92@xxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c b/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c
index ca14c3ef742e..80b8a2c66b36 100644
--- a/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c
@@ -1154,7 +1154,7 @@ static int vcn_v4_0_stop(struct amdgpu_device *adev)
fw_shared->sq.queue_mode |= FW_QUEUE_DPG_HOLD_OFF;
if (adev->pg_flags & AMD_PG_SUPPORT_VCN_DPG) {
- r = vcn_v4_0_stop_dpg_mode(adev, i);
+ vcn_v4_0_stop_dpg_mode(adev, i);
continue;
}
--
2.37.1
After value is overwritten soon right after the diff.
See:
drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c
static int vcn_v4_0_stop(struct amdgpu_device *adev)
{
volatile struct amdgpu_vcn4_fw_shared *fw_shared;
...
for (i = 0; i < adev->vcn.num_vcn_inst; ++i) {
fw_shared = adev->vcn.inst[i].fw_shared.cpu_addr;
fw_shared->sq.queue_mode |= FW_QUEUE_DPG_HOLD_OFF;
if (adev->pg_flags & AMD_PG_SUPPORT_VCN_DPG) {
r = vcn_v4_0_stop_dpg_mode(adev, i);
continue;
}
/* wait for vcn idle */
r = SOC15_WAIT_ON_RREG(VCN, i, regUVD_STATUS,
UVD_STATUS__IDLE, 0x7);
Here, any value assigned to r is overwritten before it could
be used. So the assignment in the true branch of the if statement
here can be removed.
Thanks,
-- Khalid Masum
