Hello Jens, Recently it was reported on the block layer mailing list that suspend does not work reliably neither for the legacy block layer nor for blk-mq. The purpose of this patch series is to make device suspend work reliably without affecting the hot path significantly and without introducing any race conditions between request queue cleanup and blk_get_request().
Please consider this patch series for kernel v4.15. Thanks, Bart. Bart Van Assche (5): percpu-refcount: Introduce percpu_ref_switch_to_atomic_nowait() scsi: Change the type of the second last argument of scsi_execute() block: Introduce REQ_PM and remove RQF_PM block: Make SCSI device suspend work reliably blk-mq: Implement power management support block/blk-core.c | 89 ++++++++++++++++++++++++++--------------- block/blk-mq-debugfs.c | 2 +- block/blk-mq.c | 34 ++++++++++++++++ block/blk.h | 12 ++++++ block/elevator.c | 4 +- drivers/scsi/scsi_lib.c | 15 +++---- drivers/scsi/sd.c | 4 +- drivers/scsi/ufs/ufshcd.c | 11 ++--- include/linux/blk_types.h | 2 + include/linux/blkdev.h | 3 +- include/linux/percpu-refcount.h | 1 + include/scsi/scsi_device.h | 2 +- lib/percpu-refcount.c | 21 ++++++++++ 13 files changed, 147 insertions(+), 53 deletions(-) -- 2.14.1
