Re: [PATCH 1/1] drm/amdgpu: Flush TLB after mapping for VG20+XGMI

[Tomasz Moń]

On 4/1/22 21:57, Philip Yang wrote:
For VG20 + XGMI bridge, all mappings PTEs cache in TC, this may have
stall invalid PTEs in TC because one cache line has 8 pages. Need always
flush_tlb after updating mapping.
Signed-off-by: Philip Yang <philip.y...@amd.com>
---
  drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 6 ++++++
  1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index f0aec04111a3..687c9a140645 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -837,6 +837,12 @@ int amdgpu_vm_update_range(struct amdgpu_device *adev, 
struct amdgpu_vm *vm,
                goto error_unlock;
        }
  
+	/* Vega20+XGMI where PTEs get inadvertently cached in L2 texture cache,
+        * heavy-weight flush TLB unconditionally.
+        */
+       flush_tlb |= (adev->gmc.xgmi.num_physical_nodes &&
+                     adev->ip_versions[GC_HWIP][0] == IP_VERSION(9, 4, 0));
+
        memset(&params, 0, sizeof(params));
        params.adev = adev;
        params.vm = vm;

On top of what commit does this work?

It does not apply at top of v5.18-rc1.

It does apply, but fails to compile, on top of "drm/amdkfd: Create file 
descriptor after client is added to smi_clients list" that is commit:
  * cbe879c87245ce6272afe6456dbc8ce2c8f38d64 in amd-staging-drm-next
  * e45422695c196dbc665a95526c85ff4b8752aff2 in drm-next
fetched from https://gitlab.freedesktop.org/agd5f/linux.git

The compile error is due to flush_tlb being undeclared.

Best Regards,
Tomasz Mon