[PATCH] drm/amdgpu/powerplay/smu7: fix unintialized data usage

From: Arnd Bergmann
Date: Tue Nov 08 2016 - 08:53:05 EST


A recent bugfix replaced an out-of-bounds access with direct
use of unintialized data:

drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c: In function 'smu7_patch_limits_vddc':
drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c:2033:6: error: 'vddc' may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c:2146:11: note: 'vddc' was declared here
drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c:2033:6: error: 'vddci' may be used uninitialized in this function [-Werror=maybe-uninitialized]
drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c:2146:17: note: 'vddci' was declared here
uint32_t vddc, vddci;

This initializes the data as before using the correct type.

Fixes: 77f7f71f5be1 ("drm/amdgpu/powerplay/smu7: fix static checker warning")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c b/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c
index 9e49f2777143..b2d61d043d52 100644
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c
@@ -2147,9 +2147,11 @@ static int smu7_patch_limits_vddc(struct pp_hwmgr *hwmgr,
struct smu7_hwmgr *data = (struct smu7_hwmgr *)(hwmgr->backend);

if (tab) {
+ vddc = tab->vddc;
smu7_patch_ppt_v0_with_vdd_leakage(hwmgr, &vddc,
&data->vddc_leakage);
tab->vddc = vddc;
+ vddci = tab->vddci;
smu7_patch_ppt_v0_with_vdd_leakage(hwmgr, &vddci,
&data->vddci_leakage);
tab->vddci = vddci;
--
2.9.0