From c1a66c3bc425ff93774fb2f6eefa67b83170dd7e Mon Sep 17 00:00:00 2001 From: Qiang Yu Date: Mon, 21 Feb 2022 17:53:56 +0800 Subject: [PATCH] drm/amdgpu: check vm ready by amdgpu_vm->evicting flag MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Workstation application ANSA/META v21.1.4 get this error dmesg when running CI test suite provided by ANSA/META: [drm:amdgpu_gem_va_ioctl [amdgpu]] *ERROR* Couldn't update BO_VA (-16) This is caused by: 1. create a 256MB buffer in invisible VRAM 2. CPU map the buffer and access it causes vm_fault and try to move it to visible VRAM 3. force visible VRAM space and traverse all VRAM bos to check if evicting this bo is valuable 4. when checking a VM bo (in invisible VRAM), amdgpu_vm_evictable() will set amdgpu_vm->evicting, but latter due to not in visible VRAM, won't really evict it so not add it to amdgpu_vm->evicted 5. before next CS to clear the amdgpu_vm->evicting, user VM ops ioctl will pass amdgpu_vm_ready() (check amdgpu_vm->evicted) but fail in amdgpu_vm_bo_update_mapping() (check amdgpu_vm->evicting) and get this error log This error won't affect functionality as next CS will finish the waiting VM ops. But we'd better clear the error log by checking the amdgpu_vm->evicting flag in amdgpu_vm_ready() to stop calling amdgpu_vm_bo_update_mapping() later. Another reason is amdgpu_vm->evicted list holds all BOs (both user buffer and page table), but only page table BOs' eviction prevent VM ops. amdgpu_vm->evicting flag is set only for page table BOs, so we should use evicting flag instead of evicted list in amdgpu_vm_ready(). The side effect of this change is: previously blocked VM op (user buffer in "evicted" list but no page table in it) gets done immediately. v2: update commit comments. Acked-by: Paul Menzel Reviewed-by: Christian König Signed-off-by: Qiang Yu Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c index b37fc7d7d2c7..d62190b3dd9b 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c @@ -768,11 +768,16 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm, * Check if all VM PDs/PTs are ready for updates * * Returns: - * True if eviction list is empty. + * True if VM is not evicting. */ bool amdgpu_vm_ready(struct amdgpu_vm *vm) { - return list_empty(&vm->evicted); + bool ret; + + amdgpu_vm_eviction_lock(vm); + ret = !vm->evicting; + amdgpu_vm_eviction_unlock(vm); + return ret; } /** -- 2.20.1