[AMD Official Use Only - AMD Internal Distribution Only] Ping....... Emily Deng Best Wishes >-----Original Message----- >From: Emily Deng <Emily.Deng@xxxxxxx> >Sent: Friday, February 7, 2025 6:28 PM >To: amd-gfx@xxxxxxxxxxxxxxxxxxxxx >Cc: Deng, Emily <Emily.Deng@xxxxxxx> >Subject: [PATCH] drm/amdkfd: Fix the deadlock in svm_range_restore_work > >It will hit deadlock in svm_range_restore_work ramdonly. >Detail as below: >1.svm_range_restore_work > ->svm_range_list_lock_and_flush_work > ->mmap_write_lock >2.svm_range_restore_work > ->svm_range_validate_and_map > ->amdgpu_vm_update_range > ->amdgpu_vm_ptes_update > ->amdgpu_vm_pt_alloc > ->svm_range_evict_svm_bo_worker > ->mmap_read_lock(deadlock here, because already get mmap_write_lock) > >How to fix? >Downgrade the write lock to read lock. > >Signed-off-by: Emily Deng <Emily.Deng@xxxxxxx> >--- > drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > >diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c >b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c >index bd3e20d981e0..c907e2de3dde 100644 >--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c >+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c >@@ -1841,6 +1841,7 @@ static void svm_range_restore_work(struct work_struct >*work) > mutex_lock(&process_info->lock); > svm_range_list_lock_and_flush_work(svms, mm); > mutex_lock(&svms->lock); >+ mmap_write_downgrade(mm); > > evicted_ranges = atomic_read(&svms->evicted_ranges); > >@@ -1890,7 +1891,7 @@ static void svm_range_restore_work(struct work_struct >*work) > > out_reschedule: > mutex_unlock(&svms->lock); >- mmap_write_unlock(mm); >+ mmap_read_unlock(mm); > mutex_unlock(&process_info->lock); > > /* If validation failed, reschedule another attempt */ >-- >2.34.1
