On 2023-05-19 08:02, Ma Jun wrote:
Check and pass the readonly flags when set amdgpu_ttm_tt flags
for readonly ptr pages. Otherwise, there is EPERM error returned
during the KFDExceptionTest.PermissionFaultUserPointer test on
ploaris10.
I remember you asked me about this maybe 2 weeks ago. I'm still not sure
how your test is supposed to work correctly. Someone needs to decide
whether to set KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE when registering the
userptr. How does this happen? I think you need some code that checks
that the VMA is read-only and then clears the WRITABLE flag from
mem->alloc_flags. But I don't see that anywhere. I don't think we ever
added proper support for read-only userptrs in KFD. Your patch is a
partial fix at best, and I don't see how this helps.
Two more nit-picks inline.
Signed-off-by: Ma Jun <Jun.Ma2@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index d426333e865a..85d1087439c0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -1036,10 +1036,17 @@ static int init_user_pages(struct kgd_mem *mem, uint64_t user_addr,
struct ttm_operation_ctx ctx = { true, false };
struct hmm_range *range;
int ret = 0;
+ uint32_t tt_flags = 0;
mutex_lock(&process_info->lock);
- ret = amdgpu_ttm_tt_set_userptr(&bo->tbo, user_addr, 0);
+ if (!(mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE))
+ tt_flags |= AMDGPU_GEM_USERPTR_READONLY;
+ else
+ tt_flags = 0;
This else-branch is unnecessary because you initialized tt_flags to 0 above.
+
+
Double blank lines. One is enough.
Regards,
Felix
+ ret = amdgpu_ttm_tt_set_userptr(&bo->tbo, user_addr, tt_flags);
if (ret) {
pr_err("%s: Failed to set userptr: %d\n", __func__, ret);
goto out;
