drm/radeon: fix vm deadlocks on cayman

Locking mutex in different orders just screams for
deadlocks, and some testing showed that it is actually
quite easy to trigger them.

Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Christian König 2012-06-03 16:09:43 +02:00 committed by Dave Airlie
parent 1a8ca7502c
commit bb40915582
1 changed files with 12 additions and 7 deletions

View File

@ -475,14 +475,20 @@ int radeon_vm_bo_add(struct radeon_device *rdev,
}
mutex_lock(&vm->mutex);
if (last_pfn > vm->last_pfn) {
/* release mutex and lock in right order */
mutex_unlock(&vm->mutex);
radeon_mutex_lock(&rdev->cs_mutex);
mutex_lock(&vm->mutex);
/* and check again */
if (last_pfn > vm->last_pfn) {
/* grow va space 32M by 32M */
unsigned align = ((32 << 20) >> 12) - 1;
radeon_mutex_lock(&rdev->cs_mutex);
radeon_vm_unbind_locked(rdev, vm);
radeon_mutex_unlock(&rdev->cs_mutex);
vm->last_pfn = (last_pfn + align) & ~align;
}
radeon_mutex_unlock(&rdev->cs_mutex);
}
head = &vm->va;
last_offset = 0;
list_for_each_entry(tmp, &vm->va, vm_list) {
@ -595,8 +601,8 @@ int radeon_vm_bo_rmv(struct radeon_device *rdev,
if (bo_va == NULL)
return 0;
mutex_lock(&vm->mutex);
radeon_mutex_lock(&rdev->cs_mutex);
mutex_lock(&vm->mutex);
radeon_vm_bo_update_pte(rdev, vm, bo, NULL);
radeon_mutex_unlock(&rdev->cs_mutex);
list_del(&bo_va->vm_list);
@ -641,9 +647,8 @@ void radeon_vm_fini(struct radeon_device *rdev, struct radeon_vm *vm)
struct radeon_bo_va *bo_va, *tmp;
int r;
mutex_lock(&vm->mutex);
radeon_mutex_lock(&rdev->cs_mutex);
mutex_lock(&vm->mutex);
radeon_vm_unbind_locked(rdev, vm);
radeon_mutex_unlock(&rdev->cs_mutex);