Am 2021-10-22 um 1:06 p.m. schrieb Philip Yang:
> The userptr can be unmapped by application and still registered to
> driver, restore userptr work return user pages will get -EFAULT bad
> address error. Pretend this error as succeed. GPU access this userptr
> will have VM fault later, it is better than application soft hangs with
> stalled user mode queues.
>
> Signed-off-by: Philip Yang <philip.y...@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehl...@amd.com>
> ---
> .../gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 27 ++++++++++++-------
> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 3 +++
> 2 files changed, 20 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> index cdf46bd0d8d5..6f01c6145a87 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> @@ -2041,19 +2041,26 @@ static int update_invalid_user_pages(struct
> amdkfd_process_info *process_info,
> /* Get updated user pages */
> ret = amdgpu_ttm_tt_get_user_pages(bo, bo->tbo.ttm->pages);
> if (ret) {
> - pr_debug("%s: Failed to get user pages: %d\n",
> - __func__, ret);
> + pr_debug("Failed %d to get user pages\n", ret);
> +
> + /* Return -EFAULT bad address error as success. It will
> + * fail later with a VM fault if the GPU tries to access
> + * it. Better than hanging indefinitely with stalled
> + * user mode queues.
> + *
> + * Return other error -EBUSY or -ENOMEM to retry restore
> + */
> + if (ret != -EFAULT)
> + return ret;
> + } else {
>
> - /* Return error -EBUSY or -ENOMEM, retry restore */
> - return ret;
> + /*
> + * FIXME: Cannot ignore the return code, must hold
> + * notifier_lock
> + */
> + amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
> }
>
> - /*
> - * FIXME: Cannot ignore the return code, must hold
> - * notifier_lock
> - */
> - amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
> -
> /* Mark the BO as valid unless it was invalidated
> * again concurrently.
> */
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index d784f8d3a834..ae6694f2c73d 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -693,6 +693,9 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo,
> struct page **pages)
> r = amdgpu_hmm_range_get_pages(&bo->notifier, mm, pages, start,
> ttm->num_pages, >t->range, readonly,
> false, NULL);
> + if (r)
> + pr_debug("failed %d to get user pages 0x%llx\n", r, start);
> +
> out_putmm:
> mmput(mm);
>
