| Message ID | 20170402050328.9511-1-kilobyte@angband.pl (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gpio/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/gpio/base.c index 77c649723ad7..4a57defc99b3 100644 --- a/drivers/gpu/drm/nouveau/nvkm/subdev/gpio/base.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gpio/base.c @@ -164,7 +164,7 @@ static int nvkm_gpio_fini(struct nvkm_subdev *subdev, bool suspend) { struct nvkm_gpio *gpio = nvkm_gpio(subdev); - u32 mask = (1 << gpio->func->lines) - 1; + u32 mask = (1ULL << gpio->func->lines) - 1; gpio->func->intr_mask(gpio, NVKM_GPIO_TOGGLED, mask, 0); gpio->func->intr_stat(gpio, &mask, &mask);
The code attempts to enable them, but hits an undefined behaviour by shifting by the entire register's width: int lines = 32; u32 mask = (1 << lines) - 1; // 00000000 on x86 u32 mask = (1 << lines) - 1; // ffffffff on arm (32) u32 mask = (1 << lines) - 1; // 00000000 on arm64 u32 mask = (1ULL << lines) - 1; // ffffffff everywhere Signed-off-by: Adam Borowski <kilobyte@angband.pl> --- To be honest, I can't tell the difference other than UBSAN stopping its complaints, but the current code is obviously wrong. drivers/gpu/drm/nouveau/nvkm/subdev/gpio/base.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)