Muchun Song 6bda857bcb block: fix ordering between checking QUEUE_FLAG_QUIESCED request adding ... Supposing the following scenario. CPU0 CPU1 blk_mq_insert_request() 1) store blk_mq_unquiesce_queue() blk_queue_flag_clear() 3) store blk_mq_run_hw_queues() blk_mq_run_hw_queue() if (!blk_mq_hctx_has_pending()) 4) load return blk_mq_run_hw_queue() if (blk_queue_quiesced()) 2) load return blk_mq_sched_dispatch_requests() The full memory barrier should be inserted between 1) and 2), as well as between 3) and 4) to make sure that either CPU0 sees QUEUE_FLAG_QUIESCED is cleared or CPU1 sees dispatch list or setting of bitmap of software queue. Otherwise, either CPU will not rerun the hardware queue causing starvation. So the first solution is to 1) add a pair of memory barrier to fix the problem, another solution is to 2) use hctx->queue->queue_lock to synchronize QUEUE_FLAG_QUIESCED. Here, we chose 2) to fix it since memory barrier is not easy to be maintained. Fixes: f4560ffe8c ("blk-mq: use QUEUE_FLAG_QUIESCED to quiesce queue") Cc: stable@vger.kernel.org Cc: Muchun Song <muchun.song@linux.dev> Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20241014092934.53630-3-songmuchun@bytedance.com Signed-off-by: Jens Axboe <axboe@kernel.dk>		2024-10-22 08:16:40 -06:00
..
partitions	block: add partition uuid into uevent as "PARTUUID"	2024-10-22 08:15:17 -06:00
badblocks.c	badblocks: avoid checking invalid range in badblocks_check()	2023-12-23 18:38:08 -07:00
bdev.c	for-6.12/block-20240925	2024-09-25 14:56:40 -07:00
bfq-cgroup.c	block, bfq: merge bfq_release_process_ref() into bfq_put_cooperator()	2024-09-10 16:32:09 -06:00
bfq-iosched.c	block, bfq: factor out a helper to split bfqq in bfq_init_rq()	2024-09-10 16:32:09 -06:00
bfq-iosched.h	block, bfq: remove bfq_log_bfqg()	2024-09-10 16:32:09 -06:00
bfq-wf2q.c	block, bfq: inject I/O to underutilized actuators	2023-01-29 15:18:33 -07:00
bio-integrity.c	Linux 6.11	2024-09-17 08:32:53 -06:00
bio.c	block: unpin user pages belonging to a folio at once	2024-09-11 07:24:01 -06:00
blk-cgroup-fc-appid.c	block: Replace all non-returning strlcpy with strscpy	2023-06-01 09:13:31 -06:00
blk-cgroup-rwstat.c	blk-cgroup: use group allocation/free of per-cpu counters API	2024-04-03 09:10:17 -06:00
blk-cgroup-rwstat.h	block: Use the new blk_opf_t type	2022-07-14 12:14:30 -06:00
blk-cgroup.c	blk-ioprio: remove per-disk structure	2024-07-28 16:47:51 -06:00
blk-cgroup.h	blk-cgroup: Remove unused declaration blkg_path()	2024-08-16 15:07:27 -06:00
blk-core.c	scsi: block: Don't check REQ_ATOMIC for reads	2024-08-12 18:03:38 -04:00
blk-crypto-fallback.c	block, fs: Restore the per-bio/request data lifetime fields	2024-02-06 14:31:05 +01:00
blk-crypto-internal.h	blk-crypto: remove blk_crypto_insert_cloned_request()	2023-03-16 09:35:09 -06:00
blk-crypto-profile.c	blk-crypto: use dynamic lock class for blk_crypto_profile::lock	2023-07-05 16:36:12 -06:00
blk-crypto-sysfs.c	block: make kobj_type structures constant	2023-02-09 09:38:16 -07:00
blk-crypto.c	blk-crypto: make blk_crypto_evict_key() more robust	2023-03-16 09:35:09 -06:00
blk-flush.c	for-6.11/block-20240710	2024-07-15 14:20:22 -07:00
blk-ia-ranges.c	block: make kobj_type structures constant	2023-02-09 09:38:16 -07:00
blk-integrity.c	block: fix blk_rq_map_integrity_sg kernel-doc	2024-10-02 07:15:33 -06:00
blk-ioc.c	block: replace call_rcu by kfree_rcu for simple kmem_cache_free callback	2024-10-22 08:16:40 -06:00
blk-iocost.c	blk_iocost: remove some duplicate irq disable/enables	2024-10-02 07:15:43 -06:00
blk-iolatency.c	block: add blk_time_get_ns() and blk_time_get() helpers	2024-02-05 10:07:22 -07:00
blk-ioprio.c	blk-ioprio: remove per-disk structure	2024-07-28 16:47:51 -06:00
blk-ioprio.h	blk-ioprio: remove per-disk structure	2024-07-28 16:47:51 -06:00
blk-lib.c	block: fix detection of unsupported WRITE SAME in blkdev_issue_write_zeroes	2024-08-28 08:49:25 -06:00
blk-map.c	block: don't free the integrity payload in bio_integrity_unmap_free_user	2024-07-03 10:21:16 -06:00
blk-merge.c	block: kill blk_do_io_stat() helper	2024-10-22 08:14:56 -06:00
blk-mq-cpumap.c	blk-mq: include <linux/blk-mq.h> in block/blk-mq.h	2023-04-13 06:52:29 -06:00
blk-mq-debugfs.c	block: Catch possible entries missing from rqf_name[]	2024-07-19 09:32:49 -06:00
blk-mq-debugfs.h	block: Replace zone_wlock debugfs entry with zone_wplugs entry	2024-04-17 08:44:03 -06:00
blk-mq-pci.c	blk-mq: include <linux/blk-mq.h> in block/blk-mq.h	2023-04-13 06:52:29 -06:00
blk-mq-sched.c	blk-mq: Remove the hctx 'run' debugfs attribute	2024-01-17 14:16:34 -07:00
blk-mq-sched.h	blk-mq: make sure elevator callbacks aren't called for passthrough request	2023-05-18 19:42:54 -06:00
blk-mq-sysfs.c	blk-mq: include <linux/blk-mq.h> in block/blk-mq.h	2023-04-13 06:52:29 -06:00
blk-mq-tag.c	block: Fix lockdep warning in blk_mq_mark_tag_wait	2024-08-15 19:25:03 -06:00
blk-mq-virtio.c	blk-mq: include <linux/blk-mq.h> in block/blk-mq.h	2023-04-13 06:52:29 -06:00
blk-mq.c	block: fix ordering between checking QUEUE_FLAG_QUIESCED request adding	2024-10-22 08:16:40 -06:00
blk-mq.h	block: Relocate BLK_MQ_CPU_WORK_BATCH	2024-07-19 09:32:48 -06:00
blk-pm.c	block: Remove blk_set_runtime_active()	2023-11-20 10:22:40 -07:00
blk-pm.h	block: Remove unused blk_pm_*() function definitions	2021-02-22 06:33:48 -07:00
blk-rq-qos.c	blk-rq-qos: fix crash on rq_qos_wait vs. rq_qos_wake_function race	2024-10-16 07:20:14 -06:00
blk-rq-qos.h	block: skip QUEUE_FLAG_STATS and rq-qos for passthrough io	2023-12-01 18:29:18 -07:00
blk-settings.c	block: Remove unused blk_limits_io_{min,opt}	2024-09-20 00:19:48 -06:00
blk-stat.c	blk-throttle: remove CONFIG_BLK_DEV_THROTTLING_LOW	2024-05-09 09:44:55 -06:00
blk-stat.h	block: delete redundant function declaration	2024-05-27 13:58:06 -06:00
blk-sysfs.c	block: enable passthrough command statistics	2024-10-22 08:16:32 -06:00
blk-throttle.c	Revert "blk-throttle: Fix IO hang for a corner case"	2024-10-22 08:16:40 -06:00
blk-throttle.h	blk-throttle: remove last_low_overflow_time	2024-09-10 16:31:41 -06:00
blk-timeout.c	block: blk-timeout: delete duplicated word	2020-07-31 16:29:47 -06:00
blk-wbt.c	blk-wbt: don't throttle swap writes in direct reclaim	2024-07-01 06:51:53 -06:00
blk-wbt.h	blk-wbt: remove the separate write cache tracking	2023-12-26 09:28:10 -07:00
blk-zoned.c	for-6.11/block-20240710	2024-07-15 14:20:22 -07:00
blk.h	block: add support for defining read-only partitions	2024-10-22 08:14:56 -06:00
bounce.c	block: split integrity support out of bio.h	2024-07-03 10:21:15 -06:00
bsg-lib.c	scsi: bsg: Pass dev to blk_mq_alloc_queue()	2024-05-30 20:22:15 -04:00
bsg.c	SCSI misc on 20230629	2023-06-30 11:57:07 -07:00
disk-events.c	block: move bdev_mark_dead out of disk_check_media_change	2023-10-28 13:29:23 +02:00
early-lookup.c	wrapper for access to ->bd_partno	2024-05-02 17:48:09 -04:00
elevator.c	block: return void from the queue_sysfs_entry load_module method	2024-10-22 08:16:22 -06:00
elevator.h	block: return void from the queue_sysfs_entry load_module method	2024-10-22 08:16:22 -06:00
fops.c	vfs-6.12.blocksize	2024-09-20 17:53:17 -07:00
genhd.c	block: introduce add_disk_fwnode()	2024-10-22 08:14:56 -06:00
holder.c	block: fix deadlock between bd_link_disk_holder and partition scan	2024-02-23 07:44:19 -07:00
ioctl.c	block: implement async io_uring discard cmd	2024-09-11 10:45:28 -06:00
ioprio.c	block: move __get_task_ioprio() into header file	2024-01-08 12:27:39 -07:00
Kconfig	block: remove the blk_integrity_profile structure	2024-06-14 10:20:06 -06:00
Kconfig.iosched	block: Default to use cgroup support for BFQ	2023-01-30 09:42:42 -07:00
kyber-iosched.c	blk-mq: pass a flags argument to elevator_type->insert_requests	2023-04-13 06:52:30 -06:00
Makefile	block: remove the blk_integrity_profile structure	2024-06-14 10:20:06 -06:00
mq-deadline.c	block/mq-deadline: Fix the tag reservation code	2024-07-02 08:47:45 -06:00
opal_proto.h	block: sed-opal: handle empty atoms when parsing response	2024-02-16 15:52:45 -07:00
sed-opal.c	block: sed-opal: add ioctl IOC_OPAL_SET_SID_PW	2024-10-22 08:16:40 -06:00
t10-pi.c	move asm/unaligned.h to linux/unaligned.h	2024-10-02 17:23:23 -04:00