mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-07-22 16:17:32 -04:00
amdgpu_vm_lock_by_pasid() looks up a VM by PASID and reserves its root PD with a bare amdgpu_bo_reserve(), returning the still-reserved root to the caller. A caller that then needs to reserve further BOs (for example the devcoredump IB dump) ends up nesting reservation_ww_class_mutex acquires without a ww_acquire_ctx, which lockdep flags as recursive locking. Convert the helper to take a drm_exec context and lock the root PD with drm_exec_lock_obj(). Callers now run it inside a drm_exec_until_all_locked() loop and can lock additional BOs in the same ww ticket, so there is no nested ww_mutex acquire. The drm_exec context holds its own reference on the locked root BO, so the helper no longer hands a root reference back to the caller: the root output parameter is dropped, and the transient reference taken across the PASID lookup is released before returning. The only existing caller, amdgpu_vm_handle_fault(), is updated accordingly. Its is_compute_context path, which previously dropped the root reservation around svm_range_restore_pages() and re-took it, now finalises the drm_exec context and re-initialises a fresh one; behaviour is otherwise unchanged. No functional change intended for the page-fault path. Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 14682de8ad377bf13ea66e47c26dcfea0b19a21d)