On Sun, Nov 15, 2020 at 07:04:51PM -0800, Bart Van Assche wrote: > With the current implementation the following race can happen: > * blk_pre_runtime_suspend() calls blk_freeze_queue_start() and > blk_mq_unfreeze_queue(). > * blk_queue_enter() calls blk_queue_pm_only() and that function returns > true. > * blk_queue_enter() calls blk_pm_request_resume() and that function does > not call pm_request_resume() because the queue runtime status is > RPM_ACTIVE. > * blk_pre_runtime_suspend() changes the queue status into RPM_SUSPENDING. > > Fix this race by changing the queue runtime status into RPM_SUSPENDING > before switching q_usage_counter to atomic mode. Looks good, Reviewed-by: Christoph Hellwig <hch@xxxxxx>