[PATCH 4.14 01/94] drm/amd/pp: initialize result to before oring in data

From: Greg Kroah-Hartman
Date: Mon Oct 08 2018 - 14:41:10 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

commit c4ff91dd40e2253ab6dd028011469c2c694e1e19 upstream.

The current use of result is or'ing in values and checking for
a non-zero result, however, result is not initialized to zero
so it potentially contains garbage to start with. Fix this by
initializing it to the first return from the call to
vega10_program_didt_config_registers.

Detected by cppcheck:
"(error) Uninitialized variable: result"

Fixes: 9b7b8154cdb8 ("drm/amd/powerplay: added didt support for vega10")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Acked-by: Huang Rui <ray.huang@xxxxxxx>
[Fix the subject as Colin's comment]
Signed-off-by: Huang Rui <ray.huang@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/powerplay/hwmgr/vega10_powertune.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/amd/powerplay/hwmgr/vega10_powertune.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/vega10_powertune.c
@@ -1142,7 +1142,7 @@ static int vega10_enable_psm_gc_edc_conf
for (count = 0; count < num_se; count++) {
data = GRBM_GFX_INDEX__INSTANCE_BROADCAST_WRITES_MASK | GRBM_GFX_INDEX__SH_BROADCAST_WRITES_MASK | ( count << GRBM_GFX_INDEX__SE_INDEX__SHIFT);
cgs_write_register(hwmgr->device, reg, data);
- result |= vega10_program_didt_config_registers(hwmgr, PSMSEEDCStallPatternConfig_Vega10, VEGA10_CONFIGREG_DIDT);
+ result = vega10_program_didt_config_registers(hwmgr, PSMSEEDCStallPatternConfig_Vega10, VEGA10_CONFIGREG_DIDT);
result |= vega10_program_didt_config_registers(hwmgr, PSMSEEDCStallDelayConfig_Vega10, VEGA10_CONFIGREG_DIDT);
result |= vega10_program_didt_config_registers(hwmgr, PSMSEEDCCtrlResetConfig_Vega10, VEGA10_CONFIGREG_DIDT);
result |= vega10_program_didt_config_registers(hwmgr, PSMSEEDCCtrlConfig_Vega10, VEGA10_CONFIGREG_DIDT);