[PATCH] drm/amdgpu: Need to set moved to true when evict bo

[Deng, Emily]

>-----Original Message-----
>From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> On Behalf Of
>zhoucm1
>Sent: Wednesday, August 29, 2018 10:12 AM
>To: Koenig, Christian <Christian.Koenig at amd.com>; Deng, Emily
><Emily.Deng at amd.com>; amd-gfx at lists.freedesktop.org
>Subject: Re: [PATCH] drm/amdgpu: Need to set moved to true when evict bo
>
>
>
>On 2018年08月28日 20:47, Christian König wrote:
>> Am 28.08.2018 um 14:40 schrieb Emily Deng:
>>> Fix the VMC page fault when the running sequence is as below:
>>> 1.amdgpu_gem_create_ioctl
>>> 2.ttm_bo_swapout->amdgpu_vm_bo_invalidate, as not called
>>> amdgpu_vm_bo_base_init, so won't called list_add_tail(&base->bo_list,
>>> &bo->va). Even the bo was evicted, it won't set the bo_base->moved.
>>> 3.drm_gem_open_ioctl->amdgpu_vm_bo_base_init, here only called
>>> list_move_tail(&base->vm_status, &vm->evicted), but not set the
>>> bo_base->moved.
>>> 4.amdgpu_vm_bo_map->amdgpu_vm_bo_insert_map, as the bo_base-
>>moved is
>>> not set true, the function amdgpu_vm_bo_insert_map will call
>>> list_move(&bo_va->base.vm_status, &vm->moved) 5.amdgpu_cs_ioctl won't
>>> validate the swapout bo, as it is only in the moved list, not in the
>>> evict list. So VMC page fault occurs.
>>>
>>> Signed-off-by: Emily Deng <Emily.Deng at amd.com>
>>
>> Good catch, patch is Reviewed-by: Christian König
>> <christian.koenig at amd.com>
>Really good debug, Emily, you can add my Reviewed-by: Chunming Zhou
><david1.zhou at amd.com> as well if you still don't push it yet.
David, thanks you for helping me to find out the root cause, already pushed the patch.
>Regards,
>David Zhou
>>
>>> ---
>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 1 +
>>>   1 file changed, 1 insertion(+)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>>> index 1f4b8df..015e20e 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
>>> @@ -172,6 +172,7 @@ static void amdgpu_vm_bo_base_init(struct
>>> amdgpu_vm_bo_base *base,
>>>        * is validated on next vm use to avoid fault.
>>>        * */
>>>       list_move_tail(&base->vm_status, &vm->evicted);
>>> +    base->moved = true;
>>>   }
>>>     /**
>>
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