[PATCH] amdgpu: fix integer overflow on 32-bit architectures

[Arnd Bergmann]

Multiplying 1000000000 by four overruns a 'long' variable, as clang
points out:

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c:4160:53: error: overflow in expression; result is -294967296 with type 'long' [-Werror,-Winteger-overflow]
expires = ktime_get_mono_fast_ns() + NSEC_PER_SEC * 4L;
^
Make this a 'long long' constant instead.

Fixes: 3f12acc8d6d4 ("drm/amdgpu: put the audio codec into suspend state before gpu reset V3")
Signed-off-by: Arnd Bergmann <ar...@arndb.de>
---
I'm not sure the ktime_get_mono_fast_ns() call is necessary here
either. Is it intentional because ktime_get_ns() doesn't work
during a driver suspend, or just a mistake?
---
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 6f93af972b0a..2e07e3e6b036 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -4157,7 +4157,7 @@ static int amdgpu_device_suspend_display_audio(struct amdgpu_device *adev)
* the audio controller default autosuspend delay setting.
* 4S used here is guaranteed to cover that.
*/
- expires = ktime_get_mono_fast_ns() + NSEC_PER_SEC * 4L;
+ expires = ktime_get_mono_fast_ns() + NSEC_PER_SEC * 4LL;

while (!pm_runtime_status_suspended(&(p->dev))) {
if (!pm_runtime_suspend(&(p->dev)))
--
2.26.0

[Christian König]

Am 05.05.20 um 16:15 schrieb Arnd Bergmann:

> Multiplying 1000000000 by four overruns a 'long' variable, as clang
> points out:
>
> drivers/gpu/drm/amd/amdgpu/amdgpu_device.c:4160:53: error: overflow in expression; result is -294967296 with type 'long' [-Werror,-Winteger-overflow]
> expires = ktime_get_mono_fast_ns() + NSEC_PER_SEC * 4L;
> ^
> Make this a 'long long' constant instead.
>
> Fixes: 3f12acc8d6d4 ("drm/amdgpu: put the audio codec into suspend state before gpu reset V3")
> Signed-off-by: Arnd Bergmann <ar...@arndb.de>

Reviewed-by: Christian König <christia...@amd.com>

[Nick Desaulniers]

See also https://lore.kernel.org/lkml/CADnq5_NdtZh5_RGDWKJ9c_42...@mail.gmail.com/T/#me707e09e92c6e487285e8bb382a607e4e782c249

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--
Thanks,
~Nick Desaulniers