| Message ID | 1463656317-13828-1-git-send-email-falakreyaz@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, May 19, 2016 at 01:18:10PM +0200, Christian König wrote: > Am 19.05.2016 um 13:11 schrieb Muhammad Falak R Wani: > >Use kmemdup when some other buffer is immediately copied into allocated > >region. It replaces call to allocation followed by memcpy, by a single > >call to kmemdup. > > > >Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com> > > NAK, actually using memcpy() is wrong in the first place. > > The UVD BO is in VRAM so the pointer is pointing to IO memory here, > so this should be memcpy_fromio() instead of memcpy(). > > Christian. > Should I send V2 with the required changes, and I had a query, If memcpy was wrong, did it still work or it just got un-noticed ?
Am 19.05.2016 um 13:49 schrieb Muhammad Falak R Wani: > On Thu, May 19, 2016 at 01:18:10PM +0200, Christian König wrote: >> Am 19.05.2016 um 13:11 schrieb Muhammad Falak R Wani: >>> Use kmemdup when some other buffer is immediately copied into allocated >>> region. It replaces call to allocation followed by memcpy, by a single >>> call to kmemdup. >>> >>> Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com> >> NAK, actually using memcpy() is wrong in the first place. >> >> The UVD BO is in VRAM so the pointer is pointing to IO memory here, >> so this should be memcpy_fromio() instead of memcpy(). >> >> Christian. >> > Should I send V2 with the required changes, and I had a query, I can take care of fixing this. > If memcpy was wrong, did it still work or it just got un-noticed ? Both, on X86 memcpy from IO memory works fine. Only on other architectures you run into problems with that. Regards, Christian.
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c index 01abfc2..c977ab6 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c @@ -295,12 +295,10 @@ int amdgpu_uvd_suspend(struct amdgpu_device *adev) size = amdgpu_bo_size(adev->uvd.vcpu_bo); ptr = adev->uvd.cpu_addr; - adev->uvd.saved_bo = kmalloc(size, GFP_KERNEL); + adev->uvd.saved_bo = kmemdup(ptr, size, GFP_KERNEL); if (!adev->uvd.saved_bo) return -ENOMEM; - memcpy(adev->uvd.saved_bo, ptr, size); - return 0; }
Use kmemdup when some other buffer is immediately copied into allocated region. It replaces call to allocation followed by memcpy, by a single call to kmemdup. Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)