From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Tue, 9 Jan 2018 19:18:59 +0100 Subject: drm/amdgpu: fix amdgpu_vm_pasid_fault_credit MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Git-commit: d958939afc39391c0d007a0ca43153856d63ec2a Patch-mainline: v4.16-rc1 References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166 As soon as the lock is dropped the VM pointer can be invalid. Signed-off-by: Christian König Reviewed-by: Chunming Zhou Signed-off-by: Alex Deucher Acked-by: Petr Tesarik --- drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c @@ -2477,17 +2477,21 @@ bool amdgpu_vm_pasid_fault_credit(struct spin_lock(&adev->vm_manager.pasid_lock); vm = idr_find(&adev->vm_manager.pasid_idr, pasid); - spin_unlock(&adev->vm_manager.pasid_lock); - if (!vm) + if (!vm) { /* VM not found, can't track fault credit */ + spin_unlock(&adev->vm_manager.pasid_lock); return true; + } /* No lock needed. only accessed by IRQ handler */ - if (!vm->fault_credit) + if (!vm->fault_credit) { /* Too many faults in this VM */ + spin_unlock(&adev->vm_manager.pasid_lock); return false; + } vm->fault_credit--; + spin_unlock(&adev->vm_manager.pasid_lock); return true; }