Message ID | d39a9325-87a4-4543-b6ec-1c61fca3a6fc@stanley.mountain (mailing list archive) |
---|---|
State | New |
Headers | show |
Series | drm/amdgpu: Fix shift type in amdgpu_debugfs_sdma_sched_mask_set() | expand |
On 1/8/2025 03:41, Dan Carpenter wrote: > The "mask" and "val" variables are type u64. The problem is that the > BIT() macros are type unsigned long which is just 32 bits on 32bit > systems. > > It's unlikely that people will be using this driver on 32bit kernels > and even if they did we only use the lower AMDGPU_MAX_SDMA_INSTANCES (16) > bits. So this bug does not affect anything in real life. > > Still, for correctness sake, u64 bit masks should use BIT_ULL(). > > Fixes: d2e3961ae371 ("drm/amdgpu: add amdgpu_sdma_sched_mask debugfs") > Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> > --- Applied, thanks! > drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c > index 632295bf3875..174badca27e7 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c > @@ -362,13 +362,13 @@ static int amdgpu_debugfs_sdma_sched_mask_set(void *data, u64 val) > if (!adev) > return -ENODEV; > > - mask = (1 << adev->sdma.num_instances) - 1; > + mask = BIT_ULL(adev->sdma.num_instances) - 1; > if ((val & mask) == 0) > return -EINVAL; > > for (i = 0; i < adev->sdma.num_instances; ++i) { > ring = &adev->sdma.instance[i].ring; > - if (val & (1 << i)) > + if (val & BIT_ULL(i)) > ring->sched.ready = true; > else > ring->sched.ready = false;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c index 632295bf3875..174badca27e7 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c @@ -362,13 +362,13 @@ static int amdgpu_debugfs_sdma_sched_mask_set(void *data, u64 val) if (!adev) return -ENODEV; - mask = (1 << adev->sdma.num_instances) - 1; + mask = BIT_ULL(adev->sdma.num_instances) - 1; if ((val & mask) == 0) return -EINVAL; for (i = 0; i < adev->sdma.num_instances; ++i) { ring = &adev->sdma.instance[i].ring; - if (val & (1 << i)) + if (val & BIT_ULL(i)) ring->sched.ready = true; else ring->sched.ready = false;
The "mask" and "val" variables are type u64. The problem is that the BIT() macros are type unsigned long which is just 32 bits on 32bit systems. It's unlikely that people will be using this driver on 32bit kernels and even if they did we only use the lower AMDGPU_MAX_SDMA_INSTANCES (16) bits. So this bug does not affect anything in real life. Still, for correctness sake, u64 bit masks should use BIT_ULL(). Fixes: d2e3961ae371 ("drm/amdgpu: add amdgpu_sdma_sched_mask debugfs") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> --- drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)