From f342a72e0cd39404072688aa3601df7278505ef0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Tue, 9 Jan 2018 19:18:59 +0100 Subject: [PATCH 3134/4131] drm/amdgpu: fix amdgpu_vm_pasid_fault_credit MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As soon as the lock is dropped the VM pointer can be invalid. Signed-off-by: Christian König Reviewed-by: Chunming Zhou --- drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c index e1d56f6..5c629dd 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c @@ -2549,17 +2549,21 @@ bool amdgpu_vm_pasid_fault_credit(struct amdgpu_device *adev, 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; } -- 2.7.4