drm/amdkfd: Move dma unmapping after TLB flush

Otherwise GPU may access the stale mapping and generate IOMMU
IO_PAGE_FAULT.

Move this to inside p->mutex to prevent multiple threads mapping and
unmapping concurrently race condition.

After kfd_mem_dmaunmap_attachment is removed from unmap_bo_from_gpuvm,
kfd_mem_dmaunmap_attachment is called if failed to map to GPUs, and
before free the mem attachment in case failed to unmap from GPUs.

Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 22 insertions, 4 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index c48ca5adad8a..839abd8425da 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -733,7 +733,7 @@ kfd_mem_dmaunmap_sg_bo(struct kgd_mem *mem,
 	enum dma_data_direction dir;
 
 	if (unlikely(!ttm->sg)) {
-		pr_err("SG Table of BO is UNEXPECTEDLY NULL");
+		pr_debug("SG Table of BO is NULL");
 		return;
 	}
 
@@ -1202,8 +1202,6 @@ static void unmap_bo_from_gpuvm(struct kgd_mem *mem,
 	amdgpu_vm_clear_freed(adev, vm, &bo_va->last_pt_update);
 
 	amdgpu_sync_fence(sync, bo_va->last_pt_update);
-
-	kfd_mem_dmaunmap_attachment(mem, entry);
 }
 
 static int update_gpuvm_pte(struct kgd_mem *mem,
@@ -1258,6 +1256,7 @@ static int map_bo_to_gpuvm(struct kgd_mem *mem,
 
 update_gpuvm_pte_failed:
 	unmap_bo_from_gpuvm(mem, entry, sync);
+	kfd_mem_dmaunmap_attachment(mem, entry);
 	return ret;
 }
 
@@ -1863,8 +1862,10 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
 		mem->va + bo_size * (1 + mem->aql_queue));
 
 	/* Remove from VM internal data structures */
-	list_for_each_entry_safe(entry, tmp, &mem->attachments, list)
+	list_for_each_entry_safe(entry, tmp, &mem->attachments, list) {
+		kfd_mem_dmaunmap_attachment(mem, entry);
 		kfd_mem_detach(entry);
+	}
 
 	ret = unreserve_bo_and_vms(&ctx, false, false);
 
@@ -2038,6 +2039,23 @@ out:
 	return ret;
 }
 
+void amdgpu_amdkfd_gpuvm_dmaunmap_mem(struct kgd_mem *mem, void *drm_priv)
+{
+	struct kfd_mem_attachment *entry;
+	struct amdgpu_vm *vm;
+
+	vm = drm_priv_to_vm(drm_priv);
+
+	mutex_lock(&mem->lock);
+
+	list_for_each_entry(entry, &mem->attachments, list) {
+		if (entry->bo_va->base.vm == vm)
+			kfd_mem_dmaunmap_attachment(mem, entry);
+	}
+
+	mutex_unlock(&mem->lock);
+}
+
 int amdgpu_amdkfd_gpuvm_unmap_memory_from_gpu(
 		struct amdgpu_device *adev, struct kgd_mem *mem, void *drm_priv)
 {