amdgpu_pasid_free() can be called from hardirq context via the fence
signal path:
sdma_v6_0_process_trap_irq
-> amdgpu_fence_process
-> dma_fence_signal
-> drm_sched_job_done
-> dma_fence_signal
-> amdgpu_pasid_free_cb
-> amdgpu_pasid_free
-> spin_lock(&amdgpu_pasid_idr_lock) <- hardirq context
But the lock was originally taken with plain spin_lock() in process
context (amdgpu_pasid_alloc), creating an inconsistent
{HARDIRQ-ON-W} -> {IN-HARDIRQ-W} lock state that can deadlock if an
interrupt arrives while the lock is held on the same CPU.
Use spin_lock_irqsave/spin_unlock_irqrestore for all call sites of
amdgpu_pasid_idr_lock to prevent the deadlock.
This patch applies on top of "drm/amdgpu: fix sleeping allocation
under spinlock in PASID IDR".
Fixes: 8f1de51f49be ("drm/amdgpu: prevent immediate PASID reuse case")
Cc: [email protected]
Signed-off-by: Mikhail Gavrilov <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
index 515775eab2ef..762ceb3c708a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
@@ -62,16 +62,17 @@ struct amdgpu_pasid_cb {
*/
int amdgpu_pasid_alloc(unsigned int bits)
{
+ unsigned long flags;
int pasid;
if (bits == 0)
return -EINVAL;
idr_preload(GFP_KERNEL);
- spin_lock(&amdgpu_pasid_idr_lock);
+ spin_lock_irqsave(&amdgpu_pasid_idr_lock, flags);
pasid = idr_alloc_cyclic(&amdgpu_pasid_idr, NULL, 1,
1U << bits, GFP_NOWAIT);
- spin_unlock(&amdgpu_pasid_idr_lock);
+ spin_unlock_irqrestore(&amdgpu_pasid_idr_lock, flags);
idr_preload_end();
if (pasid >= 0)
@@ -86,11 +87,12 @@ int amdgpu_pasid_alloc(unsigned int bits)
*/
void amdgpu_pasid_free(u32 pasid)
{
+ unsigned long flags;
trace_amdgpu_pasid_freed(pasid);
- spin_lock(&amdgpu_pasid_idr_lock);
+ spin_lock_irqsave(&amdgpu_pasid_idr_lock, flags);
idr_remove(&amdgpu_pasid_idr, pasid);
- spin_unlock(&amdgpu_pasid_idr_lock);
+ spin_unlock_irqrestore(&amdgpu_pasid_idr_lock, flags);
}
static void amdgpu_pasid_free_cb(struct dma_fence *fence,
@@ -633,7 +635,9 @@ void amdgpu_vmid_mgr_fini(struct amdgpu_device *adev)
*/
void amdgpu_pasid_mgr_cleanup(void)
{
- spin_lock(&amdgpu_pasid_idr_lock);
+ unsigned long flags;
+
+ spin_lock_irqsave(&amdgpu_pasid_idr_lock, flags);
idr_destroy(&amdgpu_pasid_idr);
- spin_unlock(&amdgpu_pasid_idr_lock);
+ spin_unlock_irqrestore(&amdgpu_pasid_idr_lock, flags);
}
--
2.53.0
