Messages in this thread | | | Subject | Re: [PATCH 2/3] gpu: drm: dead code elimination | From | Christian König <> | Date | Wed, 18 Dec 2019 10:52:06 +0100 |
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Am 18.12.19 um 04:50 schrieb Pan Zhang: > this set adds support for removal of gpu drm dead code. > > patch2: > `num_entries` is a data of unsigned type(compilers always treat as unsigned int) and SIZE_MAX == ~0, > > so there is a impossible condition: > '(num_entries > ((~0) - 56) / 72) => (max(0-u32) > 256204778801521549)'.
NAK, that calculation is not correct on 32-bit systems.
Christian.
> > Signed-off-by: Pan Zhang <zhangpan26@huawei.com> > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c > index 85b0515..10a7f30 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c > @@ -71,10 +71,6 @@ int amdgpu_bo_list_create(struct amdgpu_device *adev, struct drm_file *filp, > unsigned i; > int r; > > - if (num_entries > (SIZE_MAX - sizeof(struct amdgpu_bo_list)) > - / sizeof(struct amdgpu_bo_list_entry)) > - return -EINVAL; > - > size = sizeof(struct amdgpu_bo_list); > size += num_entries * sizeof(struct amdgpu_bo_list_entry); > list = kvmalloc(size, GFP_KERNEL);
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