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2021-08-27Merge tag 'block-5.14-2021-08-27' of git://git.kernel.dk/linux-blockLinus Torvalds1-42/+16
Pull block fixes from Jens Axboe: - Revert the mq-deadline priority handling, it's causing serious performance regressions. While experimental patches exists to fix this up, it's too late to do so now. Revert it and re-do it properly for 5.15 instead. - Fix a NULL vs IS_ERR() regression in this release (Dan) - Fix a mq-deadline accounting regression in this release (Bart) - Mark cryptoloop as deprecated. It's broken and dm-crypt fully supports it, and it's actively intefering with loop. Plan on removal for 5.16 (Christoph) * tag 'block-5.14-2021-08-27' of git://git.kernel.dk/linux-block: cryptoloop: add a deprecation warning pd: fix a NULL vs IS_ERR() check Revert "block/mq-deadline: Prioritize high-priority requests" mq-deadline: Fix request accounting
2021-08-26Revert "block/mq-deadline: Prioritize high-priority requests"Jens Axboe1-37/+5
This reverts commit fb926032b3209300f9dc454a36b8299582ae545c. Zhen reports that this commit slows down mq-deadline on a 128 thread box, going from 258K IOPS to 170-180K. My testing shows that Optane gen2 IOPS goes from 2.3M IOPS to 1.2M IOPS on a 64 thread box. Looking in detail at the code, the main culprit here is needing to sum percpu counters in the dispatch hot path, leading to very high CPU utilization there. To make matters worse, the code currently needs to sum 2 percpu counters, and it does so in the most naive way of iterating possible CPUs _twice_. Since we're close to release, revert this commit and we can re-do it with regular per-priority counters instead for the 5.15 kernel. Link: https://lore.kernel.org/linux-block/20210826144039.2143-1-thunder.leizhen@huawei.com/ Reported-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-24mq-deadline: Fix request accountingBart Van Assche1-5/+11
The block layer may call the I/O scheduler .finish_request() callback without having called the .insert_requests() callback. Make sure that the mq-deadline I/O statistics are correct if the block layer inserts an I/O request that bypasses the I/O scheduler. This patch prevents that lower priority I/O is delayed longer than necessary for mixed I/O priority workloads. Cc: Niklas Cassel <Niklas.Cassel@wdc.com> Cc: Damien Le Moal <damien.lemoal@wdc.com> Cc: Hannes Reinecke <hare@suse.de> Reported-by: Niklas Cassel <Niklas.Cassel@wdc.com> Fixes: 08a9ad8bf607 ("block/mq-deadline: Add cgroup support") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210824170520.1659173-1-bvanassche@acm.org Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com> Tested-by: Niklas Cassel <niklas.cassel@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-21Merge tag 'block-5.14-2021-08-20' of git://git.kernel.dk/linux-blockLinus Torvalds4-32/+20
Pull block fixes from Jens Axboe: "Three fixes from Ming Lei that should go into 5.14: - Fix for a kernel panic when iterating over tags for some cases where a flush request is present, a regression in this cycle. - Request timeout fix - Fix flush request checking" * tag 'block-5.14-2021-08-20' of git://git.kernel.dk/linux-block: blk-mq: fix is_flush_rq blk-mq: fix kernel panic during iterating over flush request blk-mq: don't grab rq's refcount in blk_mq_check_expired()
2021-08-17blk-mq: fix is_flush_rqMing Lei3-6/+7
is_flush_rq() is called from bt_iter()/bt_tags_iter(), and runs the following check: hctx->fq->flush_rq == req but the passed hctx from bt_iter()/bt_tags_iter() may be NULL because: 1) memory re-order in blk_mq_rq_ctx_init(): rq->mq_hctx = data->hctx; ... refcount_set(&rq->ref, 1); OR 2) tag re-use and ->rqs[] isn't updated with new request. Fix the issue by re-writing is_flush_rq() as: return rq->end_io == flush_end_io; which turns out simpler to follow and immune to data race since we have ordered WRITE rq->end_io and refcount_set(&rq->ref, 1). Fixes: 2e315dc07df0 ("blk-mq: grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter") Cc: "Blank-Burian, Markus, Dr." <blankburian@uni-muenster.de> Cc: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210818010925.607383-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-17blk-mq: fix kernel panic during iterating over flush requestMing Lei2-1/+8
For fixing use-after-free during iterating over requests, we grabbed request's refcount before calling ->fn in commit 2e315dc07df0 ("blk-mq: grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter"). Turns out this way may cause kernel panic when iterating over one flush request: 1) old flush request's tag is just released, and this tag is reused by one new request, but ->rqs[] isn't updated yet 2) the flush request can be re-used for submitting one new flush command, so blk_rq_init() is called at the same time 3) meantime blk_mq_queue_tag_busy_iter() is called, and old flush request is retrieved from ->rqs[tag]; when blk_mq_put_rq_ref() is called, flush_rq->end_io may not be updated yet, so NULL pointer dereference is triggered in blk_mq_put_rq_ref(). Fix the issue by calling refcount_set(&flush_rq->ref, 1) after flush_rq->end_io is set. So far the only other caller of blk_rq_init() is scsi_ioctl_reset() in which the request doesn't enter block IO stack and the request reference count isn't used, so the change is safe. Fixes: 2e315dc07df0 ("blk-mq: grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter") Reported-by: "Blank-Burian, Markus, Dr." <blankburian@uni-muenster.de> Tested-by: "Blank-Burian, Markus, Dr." <blankburian@uni-muenster.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: John Garry <john.garry@huawei.com> Link: https://lore.kernel.org/r/20210811142624.618598-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-17blk-mq: don't grab rq's refcount in blk_mq_check_expired()Ming Lei1-25/+5
Inside blk_mq_queue_tag_busy_iter() we already grabbed request's refcount before calling ->fn(), so needn't to grab it one more time in blk_mq_check_expired(). Meantime remove extra request expire check in blk_mq_check_expired(). Cc: Keith Busch <kbusch@kernel.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: John Garry <john.garry@huawei.com> Link: https://lore.kernel.org/r/20210811155202.629575-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-13Merge tag 'block-5.14-2021-08-13' of git://git.kernel.dk/linux-blockLinus Torvalds7-313/+22
Pull block fixes from Jens Axboe: "A few fixes for block that should go into 5.14: - Revert the mq-deadline cgroup addition. More work is needed on this front, let's revert it for now and get it right before having it in a released kernel (Tejun) - blk-iocost lockdep fix (Ming) - nbd double completion fix (Xie) - Fix for non-idling when clearing the shared tag flag (Yu)" * tag 'block-5.14-2021-08-13' of git://git.kernel.dk/linux-block: nbd: Aovid double completion of a request blk-mq: clear active_queues before clearing BLK_MQ_F_TAG_QUEUE_SHARED Revert "block/mq-deadline: Add cgroup support" blk-iocost: fix lockdep warning on blkcg->lock
2021-08-13blk-mq: clear active_queues before clearing BLK_MQ_F_TAG_QUEUE_SHAREDYu Kuai1-2/+4
We run a test that delete and recover devcies frequently(two devices on the same host), and we found that 'active_queues' is super big after a period of time. If device a and device b share a tag set, and a is deleted, then blk_mq_exit_queue() will clear BLK_MQ_F_TAG_QUEUE_SHARED because there is only one queue that are using the tag set. However, if b is still active, the active_queues of b might never be cleared even if b is deleted. Thus clear active_queues before BLK_MQ_F_TAG_QUEUE_SHARED is cleared. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210731062130.1533893-1-yukuai3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-11Revert "block/mq-deadline: Add cgroup support"Tejun Heo5-307/+14
This reverts commit 08a9ad8bf607 ("block/mq-deadline: Add cgroup support") and a follow-up commit c06bc5a3fb42 ("block/mq-deadline: Remove a WARN_ON_ONCE() call"). The added cgroup support has the following issues: * It breaks cgroup interface file format rule by adding custom elements to a nested key-value file. * It registers mq-deadline as a cgroup-aware policy even though all it's doing is collecting per-cgroup stats. Even if we need these stats, this isn't the right way to add them. * It hasn't been reviewed from cgroup side. Cc: Bart Van Assche <bvanassche@acm.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-09blk-iocost: fix lockdep warning on blkcg->lockMing Lei1-4/+4
blkcg->lock depends on q->queue_lock which may depend on another driver lock required in irq context, one example is dm-thin: Chain exists of: &pool->lock#3 --> &q->queue_lock --> &blkcg->lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&blkcg->lock); local_irq_disable(); lock(&pool->lock#3); lock(&q->queue_lock); <Interrupt> lock(&pool->lock#3); Fix the issue by using spin_lock_irq(&blkcg->lock) in ioc_weight_write(). Cc: Tejun Heo <tj@kernel.org> Reported-by: Bruno Goncalves <bgoncalv@redhat.com> Link: https://lore.kernel.org/linux-block/CA+QYu4rzz6079ighEanS3Qq_Dmnczcf45ZoJoHKVLVATTo1e4Q@mail.gmail.com/T/#u Signed-off-by: Ming Lei <ming.lei@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20210803070608.1766400-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-09Merge branch 'for-5.14-fixes' of ↵Linus Torvalds1-6/+8
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fix from Tejun Heo: "One commit to fix a possible A-A deadlock around u64_stats_sync on 32bit machines caused by updating it without disabling IRQ when it may be read from IRQ context" * 'for-5.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: rstat: fix A-A deadlock on 32bit around u64_stats_sync
2021-08-07Merge tag 'block-5.14-2021-08-07' of git://git.kernel.dk/linux-blockLinus Torvalds3-3/+7
Pull block fixes from Jens Axboe: "A few minor fixes: - Fix ldm kernel-doc warning (Bart) - Fix adding offset twice for DMA address in n64cart (Christoph) - Fix use-after-free in dasd path handling (Stefan) - Order kyber insert trace correctly (Vincent) - raid1 errored write handling fix (Wei) - Fix blk-iolatency queue get failure handling (Yu)" * tag 'block-5.14-2021-08-07' of git://git.kernel.dk/linux-block: kyber: make trace_block_rq call consistent with documentation block/partitions/ldm.c: Fix a kernel-doc warning blk-iolatency: error out if blk_get_queue() failed in iolatency_set_limit() n64cart: fix the dma address in n64cart_do_bvec s390/dasd: fix use after free in dasd path handling md/raid10: properly indicate failure when ending a failed write request
2021-08-06kyber: make trace_block_rq call consistent with documentationVincent Fu1-1/+1
The kyber ioscheduler calls trace_block_rq_insert() *after* the request is added to the queue but the documentation for trace_block_rq_insert() says that the call should be made *before* the request is added to the queue. Move the tracepoint for the kyber ioscheduler so that it is consistent with the documentation. Signed-off-by: Vincent Fu <vincent.fu@samsung.com> Link: https://lore.kernel.org/r/20210804194913.10497-1-vincent.fu@samsung.com Reviewed by: Adam Manzanares <a.manzanares@samsung.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-05block/partitions/ldm.c: Fix a kernel-doc warningBart Van Assche1-1/+1
Fix the following kernel-doc warning that appears when building with W=1: block/partitions/ldm.c:31: warning: expecting prototype for ldm(). Prototype was for ldm_debug() instead Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210805173447.3249906-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-05blk-iolatency: error out if blk_get_queue() failed in iolatency_set_limit()Yu Kuai1-1/+5
If queue is dying while iolatency_set_limit() is in progress, blk_get_queue() won't increment the refcount of the queue. However, blk_put_queue() will still decrement the refcount later, which will cause the refcout to be unbalanced. Thus error out in such case to fix the problem. Fixes: 8c772a9bfc7c ("blk-iolatency: fix IO hang due to negative inflight counter") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20210805124645.543797-1-yukuai3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-30Merge tag 'block-5.14-2021-07-30' of git://git.kernel.dk/linux-blockLinus Torvalds3-20/+11
Pull block fixes from Jens Axboe: - gendisk freeing fix (Christoph) - blk-iocost wake ordering fix (Tejun) - tag allocation error handling fix (John) - loop locking fix. While this isn't the prettiest fix in the world, nobody has any good alternatives for 5.14. Something to likely revisit for 5.15. (Tetsuo) * tag 'block-5.14-2021-07-30' of git://git.kernel.dk/linux-block: block: delay freeing the gendisk blk-iocost: fix operation ordering in iocg_wake_fn() blk-mq-sched: Fix blk_mq_sched_alloc_tags() error handling loop: reintroduce global lock for safe loop_validate_file() traversal
2021-07-27block: delay freeing the gendiskChristoph Hellwig1-2/+1
blkdev_get_no_open acquires a reference to the block_device through the block device inode and then tries to acquire a device model reference to the gendisk. But at this point the disk migh already be freed (although the race is free). Fix this by only freeing the gendisk from the whole device bdevs ->free_inode callback as well. Fixes: 22ae8ce8b892 ("block: simplify bdev/disk lookup in blkdev_get") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210722075402.983367-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-27blk-iocost: fix operation ordering in iocg_wake_fn()Tejun Heo1-5/+6
iocg_wake_fn() open-codes wait_queue_entry removal and wakeup because it wants the wq_entry to be always removed whether it ended up waking the task or not. finish_wait() tests whether wq_entry needs removal without grabbing the wait_queue lock and expects the waker to use list_del_init_careful() after all waking operations are complete, which iocg_wake_fn() didn't do. The operation order was wrong and the regular list_del_init() was used. The result is that if a waiter wakes up racing the waker, it can free pop the wq_entry off stack before the waker is still looking at it, which can lead to a backtrace like the following. [7312084.588951] general protection fault, probably for non-canonical address 0x586bf4005b2b88: 0000 [#1] SMP ... [7312084.647079] RIP: 0010:queued_spin_lock_slowpath+0x171/0x1b0 ... [7312084.858314] Call Trace: [7312084.863548] _raw_spin_lock_irqsave+0x22/0x30 [7312084.872605] try_to_wake_up+0x4c/0x4f0 [7312084.880444] iocg_wake_fn+0x71/0x80 [7312084.887763] __wake_up_common+0x71/0x140 [7312084.895951] iocg_kick_waitq+0xe8/0x2b0 [7312084.903964] ioc_rqos_throttle+0x275/0x650 [7312084.922423] __rq_qos_throttle+0x20/0x30 [7312084.930608] blk_mq_make_request+0x120/0x650 [7312084.939490] generic_make_request+0xca/0x310 [7312084.957600] submit_bio+0x173/0x200 [7312084.981806] swap_readpage+0x15c/0x240 [7312084.989646] read_swap_cache_async+0x58/0x60 [7312084.998527] swap_cluster_readahead+0x201/0x320 [7312085.023432] swapin_readahead+0x2df/0x450 [7312085.040672] do_swap_page+0x52f/0x820 [7312085.058259] handle_mm_fault+0xa16/0x1420 [7312085.066620] do_page_fault+0x2c6/0x5c0 [7312085.074459] page_fault+0x2f/0x40 Fix it by switching to list_del_init_careful() and putting it at the end. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Rik van Riel <riel@surriel.com> Fixes: 7caa47151ab2 ("blkcg: implement blk-iocost") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-27cgroup: rstat: fix A-A deadlock on 32bit around u64_stats_syncTejun Heo1-6/+8
0fa294fb1985 ("cgroup: Replace cgroup_rstat_mutex with a spinlock") added cgroup_rstat_flush_irqsafe() allowing flushing to happen from the irq context. However, rstat paths use u64_stats_sync to synchronize access to 64bit stat counters on 32bit machines. u64_stats_sync is implemented using seq_lock and trying to read from an irq context can lead to A-A deadlock if the irq happens to interrupt the stat update. Fix it by using the irqsafe variants - u64_stats_update_begin_irqsave() and u64_stats_update_end_irqrestore() - in the update paths. Note that none of this matters on 64bit machines. All these are just for 32bit SMP setups. Note that the interface was introduced way back, its first and currently only use was recently added by 2d146aa3aa84 ("mm: memcontrol: switch to rstat"). Stable tagging targets this commit. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Rik van Riel <riel@surriel.com> Fixes: 2d146aa3aa84 ("mm: memcontrol: switch to rstat") Cc: stable@vger.kernel.org # v5.13+
2021-07-27blk-mq-sched: Fix blk_mq_sched_alloc_tags() error handlingJohn Garry1-13/+4
If the blk_mq_sched_alloc_tags() -> blk_mq_alloc_rqs() call fails, then we call blk_mq_sched_free_tags() -> blk_mq_free_rqs(). It is incorrect to do so, as any rqs would have already been freed in the blk_mq_alloc_rqs() call. Fix by calling blk_mq_free_rq_map() only directly. Fixes: 6917ff0b5bd41 ("blk-mq-sched: refactor scheduler initialization") Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/1627378373-148090-1-git-send-email-john.garry@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-09Merge tag 'block-5.14-2021-07-08' of git://git.kernel.dk/linux-blockLinus Torvalds9-27/+63
Pull more block updates from Jens Axboe: "A combination of changes that ended up depending on both the driver and core branch (and/or the IDE removal), and a few late arriving fixes. In detail: - Fix io ticks wrap-around issue (Chunguang) - nvme-tcp sock locking fix (Maurizio) - s390-dasd fixes (Kees, Christoph) - blk_execute_rq polling support (Keith) - blk-cgroup RCU iteration fix (Yu) - nbd backend ID addition (Prasanna) - Partition deletion fix (Yufen) - Use blk_mq_alloc_disk for mmc, mtip32xx, ubd (Christoph) - Removal of now dead block request types due to IDE removal (Christoph) - Loop probing and control device cleanups (Christoph) - Device uevent fix (Christoph) - Misc cleanups/fixes (Tetsuo, Christoph)" * tag 'block-5.14-2021-07-08' of git://git.kernel.dk/linux-block: (34 commits) blk-cgroup: prevent rcu_sched detected stalls warnings while iterating blkgs block: fix the problem of io_ticks becoming smaller nvme-tcp: can't set sk_user_data without write_lock loop: remove unused variable in loop_set_status() block: remove the bdgrab in blk_drop_partitions block: grab a device refcount in disk_uevent s390/dasd: Avoid field over-reading memcpy() dasd: unexport dasd_set_target_state block: check disk exist before trying to add partition ubd: remove dead code in ubd_setup_common nvme: use return value from blk_execute_rq() block: return errors from blk_execute_rq() nvme: use blk_execute_rq() for passthrough commands block: support polling through blk_execute_rq block: remove REQ_OP_SCSI_{IN,OUT} block: mark blk_mq_init_queue_data static loop: rewrite loop_exit using idr_for_each_entry loop: split loop_lookup loop: don't allow deleting an unspecified loop device loop: move loop_ctl_mutex locking into loop_add ...
2021-07-07blk-cgroup: prevent rcu_sched detected stalls warnings while iterating blkgsYu Kuai1-0/+15
We run a test that create millions of cgroups and blkgs, and then trigger blkg_destroy_all(). blkg_destroy_all() will hold spin lock for a long time in such situation. Thus release the lock when a batch of blkgs are destroyed. blkcg_activate_policy() and blkcg_deactivate_policy() might have the same problem, however, as they are basically only called from module init/exit paths, let's leave them alone for now. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20210707015649.1929797-1-yukuai3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-07block: fix the problem of io_ticks becoming smallerChunguang Xu1-1/+1
On the IO submission path, blk_account_io_start() may interrupt the system interruption. When the interruption returns, the value of part->stamp may have been updated by other cores, so the time value collected before the interruption may be less than part-> stamp. So when this happens, we should do nothing to make io_ticks more accurate? For kernels less than 5.0, this may cause io_ticks to become smaller, which in turn may cause abnormal ioutil values. Signed-off-by: Chunguang Xu <brookxu@tencent.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/1625521646-1069-1-git-send-email-brookxu.cn@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-04scsi: blkcg: Fix application ID config optionsMartin K. Petersen1-1/+1
Commit d2bcbeab4200 ("scsi: blkcg: Add app identifier support for blkcg") introduced an FC_APPID config option under SCSI. However, the added config option is not used anywhere. Simply remove it. The block layer BLK_CGROUP_FC_APPID config option is what actually controls whether the application ID code should be built or not. Make this option dependent on NVMe over FC since that is currently the only transport which supports the capability. Fixes: d2bcbeab4200 ("scsi: blkcg: Add app identifier support for blkcg") Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-02Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds4-7/+21
Pull SCSI updates from James Bottomley: "This series consists of the usual driver updates (ufs, ibmvfc, megaraid_sas, lpfc, elx, mpi3mr, qedi, iscsi, storvsc, mpt3sas) with elx and mpi3mr being new drivers. The major core change is a rework to drop the status byte handling macros and the old bit shifted definitions and the rest of the updates are minor fixes" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (287 commits) scsi: aha1740: Avoid over-read of sense buffer scsi: arcmsr: Avoid over-read of sense buffer scsi: ips: Avoid over-read of sense buffer scsi: ufs: ufs-mediatek: Add missing of_node_put() in ufs_mtk_probe() scsi: elx: libefc: Fix IRQ restore in efc_domain_dispatch_frame() scsi: elx: libefc: Fix less than zero comparison of a unsigned int scsi: elx: efct: Fix pointer error checking in debugfs init scsi: elx: efct: Fix is_originator return code type scsi: elx: efct: Fix link error for _bad_cmpxchg scsi: elx: efct: Eliminate unnecessary boolean check in efct_hw_command_cancel() scsi: elx: efct: Do not use id uninitialized in efct_lio_setup_session() scsi: elx: efct: Fix error handling in efct_hw_init() scsi: elx: efct: Remove redundant initialization of variable lun scsi: elx: efct: Fix spelling mistake "Unexected" -> "Unexpected" scsi: lpfc: Fix build error in lpfc_scsi.c scsi: target: iscsi: Remove redundant continue statement scsi: qla4xxx: Remove redundant continue statement scsi: ppa: Switch to use module_parport_driver() scsi: imm: Switch to use module_parport_driver() scsi: mpt3sas: Fix error return value in _scsih_expander_add() ...
2021-07-02Merge tag 'asm-generic-unaligned-5.14' of ↵Linus Torvalds3-17/+12
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm/unaligned.h unification from Arnd Bergmann: "Unify asm/unaligned.h around struct helper The get_unaligned()/put_unaligned() helpers are traditionally architecture specific, with the two main variants being the "access-ok.h" version that assumes unaligned pointer accesses always work on a particular architecture, and the "le-struct.h" version that casts the data to a byte aligned type before dereferencing, for architectures that cannot always do unaligned accesses in hardware. Based on the discussion linked below, it appears that the access-ok version is not realiable on any architecture, but the struct version probably has no downsides. This series changes the code to use the same implementation on all architectures, addressing the few exceptions separately" Link: https://lore.kernel.org/lkml/75d07691-1e4f-741f-9852-38c0b4f520bc@synopsys.com/ Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100363 Link: https://lore.kernel.org/lkml/20210507220813.365382-14-arnd@kernel.org/ Link: git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic.git unaligned-rework-v2 Link: https://lore.kernel.org/lkml/CAHk-=whGObOKruA_bU3aPGZfoDqZM1_9wBkwREp0H0FgR-90uQ@mail.gmail.com/ * tag 'asm-generic-unaligned-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: simplify asm/unaligned.h asm-generic: uaccess: 1-byte access is always aligned netpoll: avoid put_unaligned() on single character mwifiex: re-fix for unaligned accesses apparmor: use get_unaligned() only for multi-byte words partitions: msdos: fix one-byte get_unaligned() asm-generic: unaligned always use struct helpers asm-generic: unaligned: remove byteshift helpers powerpc: use linux/unaligned/le_struct.h on LE power7 m68k: select CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS sh: remove unaligned access for sh4a openrisc: always use unaligned-struct header asm-generic: use asm-generic/unaligned.h for most architectures
2021-07-01block: remove the bdgrab in blk_drop_partitionsChristoph Hellwig1-5/+1
There is no need to hold a bdev reference when removing the partition. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210701081638.246552-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01block: grab a device refcount in disk_ueventChristoph Hellwig1-2/+2
Sending uevents requires the struct device to be alive. To ensure that grab the device refcount instead of just an inode reference. Fixes: bc359d03c7ec ("block: add a disk_uevent helper") Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210701081638.246552-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30block: check disk exist before trying to add partitionYufen Yu1-7/+16
If disk have been deleted, we should return fail for ioctl BLKPG_DEL_PARTITION. Otherwise, the directory /sys/class/block may remain invalid symlinks file. The race as following: blkdev_open del_gendisk disk->flags &= ~GENHD_FL_UP; blk_drop_partitions blkpg_ioctl bdev_add_partition add_partition device_add device_add_class_symlinks ioctl may add_partition after del_gendisk() have tried to delete partitions. Then, symlinks file will be created. Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Yufen Yu <yuyufen@huawei.com> Link: https://lore.kernel.org/r/20210610023241.3646241-1-yuyufen@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30Merge tag 'for-5.14/dm-changes' of ↵Linus Torvalds1-27/+92
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Various DM persistent-data library improvements and fixes that benefit both the DM thinp and cache targets. - A few small DM kcopyd efficiency improvements. - Significant zoned related block core, DM core and DM zoned target changes that culminate with adding zoned append emulation (which is required to properly fix DM crypt's zoned support). - Various DM writecache target changes that improve efficiency. Adds an optional "metadata_only" feature that only promotes bios flagged with REQ_META. But the most significant improvement is writecache's ability to pause writeback, for a confiurable time, if/when the working set is larger than the cache (and the cache is full) -- this ensures performance is no worse than the slower origin device. * tag 'for-5.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits) dm writecache: make writeback pause configurable dm writecache: pause writeback if cache full and origin being written directly dm io tracker: factor out IO tracker dm btree remove: assign new_root only when removal succeeds dm zone: fix dm_revalidate_zones() memory allocation dm ps io affinity: remove redundant continue statement dm writecache: add optional "metadata_only" parameter dm writecache: add "cleaner" and "max_age" to Documentation dm writecache: write at least 4k when committing dm writecache: flush origin device when writing and cache is full dm writecache: have ssd writeback wait if the kcopyd workqueue is busy dm writecache: use list_move instead of list_del/list_add in writecache_writeback() dm writecache: commit just one block, not a full page dm writecache: remove unused gfp_t argument from wc_add_block() dm crypt: Fix zoned block device support dm: introduce zone append emulation dm: rearrange core declarations for extended use from dm-zone.c block: introduce BIO_ZONE_WRITE_LOCKED bio flag block: introduce bio zone helpers block: improve handling of all zones reset operation ...
2021-06-30block: return errors from blk_execute_rq()Keith Busch1-2/+5
The synchronous blk_execute_rq() had not provided a way for its callers to know if its request was successful or not. Return the blk_status_t result of the request. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210610214437.641245-4-kbusch@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30block: support polling through blk_execute_rqKeith Busch1-1/+17
Poll for completions if the request's hctx is a polling type. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210610214437.641245-2-kbusch@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30block: remove REQ_OP_SCSI_{IN,OUT}Christoph Hellwig4-7/+5
With the legacy IDE driver gone drivers now use either REQ_OP_DRV_* or REQ_OP_SCSI_*, so unify the two concepts of passthrough requests into a single one. Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30block: mark blk_mq_init_queue_data staticChristoph Hellwig1-2/+1
All driver uses are gone now. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210624081012.256464-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30Merge tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+1
Pull block driver updates from Jens Axboe: "Pretty calm round, mostly just NVMe and a bit of MD: - NVMe updates (via Christoph) - improve the APST configuration algorithm (Alexey Bogoslavsky) - look for StorageD3Enable on companion ACPI device (Mario Limonciello) - allow selecting the network interface for TCP connections (Martin Belanger) - misc cleanups (Amit Engel, Chaitanya Kulkarni, Colin Ian King, Christoph) - move the ACPI StorageD3 code to drivers/acpi/ and add quirks for certain AMD CPUs (Mario Limonciello) - zoned device support for nvmet (Chaitanya Kulkarni) - fix the rules for changing the serial number in nvmet (Noam Gottlieb) - various small fixes and cleanups (Dan Carpenter, JK Kim, Chaitanya Kulkarni, Hannes Reinecke, Wesley Sheng, Geert Uytterhoeven, Daniel Wagner) - MD updates (Via Song) - iostats rewrite (Guoqing Jiang) - raid5 lock contention optimization (Gal Ofri) - Fall through warning fix (Gustavo) - Misc fixes (Gustavo, Jiapeng)" * tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block: (78 commits) nvmet: use NVMET_MAX_NAMESPACES to set nn value loop: Fix missing discard support when using LOOP_CONFIGURE nvme.h: add missing nvme_lba_range_type endianness annotations nvme: remove zeroout memset call for struct nvme-pci: remove zeroout memset call for struct nvmet: remove zeroout memset call for struct nvmet: add ZBD over ZNS backend support nvmet: add Command Set Identifier support nvmet: add nvmet_req_bio put helper for backends nvmet: add req cns error complete helper block: export blk_next_bio() nvmet: remove local variable nvmet: use nvme status value directly nvmet: use u32 type for the local variable nsid nvmet: use u32 for nvmet_subsys max_nsid nvmet: use req->cmd directly in file-ns fast path nvmet: use req->cmd directly in bdev-ns fast path nvmet: make ver stable once connection established nvmet: allow mn change if subsys not discovered nvmet: make sn stable once connection was established ...
2021-06-30Merge tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds34-1757/+2911
Pull core block updates from Jens Axboe: - disk events cleanup (Christoph) - gendisk and request queue allocation simplifications (Christoph) - bdev_disk_changed cleanups (Christoph) - IO priority improvements (Bart) - Chained bio completion trace fix (Edward) - blk-wbt fixes (Jan) - blk-wbt enable/disable fix (Zhang) - Scheduler dispatch improvements (Jan, Ming) - Shared tagset scheduler improvements (John) - BFQ updates (Paolo, Luca, Pietro) - BFQ lock inversion fix (Jan) - Documentation improvements (Kir) - CLONE_IO block cgroup fix (Tejun) - Remove of ancient and deprecated block dump feature (zhangyi) - Discard merge fix (Ming) - Misc fixes or followup fixes (Colin, Damien, Dan, Long, Max, Thomas, Yang) * tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block: (129 commits) block: fix discard request merge block/mq-deadline: Remove a WARN_ON_ONCE() call blk-mq: update hctx->dispatch_busy in case of real scheduler blk: Fix lock inversion between ioc lock and bfqd lock bfq: Remove merged request already in bfq_requests_merged() block: pass a gendisk to bdev_disk_changed block: move bdev_disk_changed block: add the events* attributes to disk_attrs block: move the disk events code to a separate file block: fix trace completion for chained bio block/partitions/msdos: Fix typo inidicator -> indicator block, bfq: reset waker pointer with shared queues block, bfq: check waker only for queues with no in-flight I/O block, bfq: avoid delayed merge of async queues block, bfq: boost throughput by extending queue-merging times block, bfq: consider also creation time in delayed stable merge block, bfq: fix delayed stable merge check block, bfq: let also stably merged queues enjoy weight raising blk-wbt: make sure throttle is enabled properly blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled() ...
2021-06-29block: fix discard request mergeMing Lei1-2/+6
ll_new_hw_segment() is reached only in case of single range discard merge, and we don't have max discard segment size limit actually, so it is wrong to run the following check: if (req->nr_phys_segments + nr_phys_segs > blk_rq_get_max_segments(req)) it may be always false since req->nr_phys_segments is initialized as one, and bio's segment count is still 1, blk_rq_get_max_segments(reg) is 1 too. Fix the issue by not doing the check and bypassing the calculation of discard request's nr_phys_segments. Based on analysis from Wang Shanker. Cc: Christoph Hellwig <hch@lst.de> Reported-by: Wang Shanker <shankerwangmiao@gmail.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210628023312.1903255-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-27block/mq-deadline: Remove a WARN_ON_ONCE() callBart Van Assche1-1/+0
The purpose of the WARN_ON_ONCE() statement in dd_insert_request() is to verify that dd_prepare_request() cleared rq->elv.priv[0]. Since dd_prepare_request() is called during request initialization but not if a request is requeued, a warning is triggered if a request is requeued. Fix this by removing the WARN_ON_ONCE() statement. This patch suppresses the following kernel warning: WARNING: CPU: 28 PID: 432 at block/mq-deadline-main.c:740 dd_insert_request+0x4d4/0x5b0 Workqueue: kblockd blk_mq_requeue_work Call Trace: dd_insert_requests+0xfa/0x130 blk_mq_sched_insert_request+0x22c/0x240 blk_mq_requeue_work+0x21c/0x2d0 process_one_work+0x4c2/0xa70 worker_thread+0x2e5/0x6d0 kthread+0x21c/0x250 ret_from_fork+0x1f/0x30 Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Fixes: 08a9ad8bf607 ("block/mq-deadline: Add cgroup support") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210627211112.12720-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-25blk-mq: update hctx->dispatch_busy in case of real schedulerMing Lei1-3/+0
Commit 6e6fcbc27e77 ("blk-mq: support batching dispatch in case of io") starts to support io batching submission by using hctx->dispatch_busy. However, blk_mq_update_dispatch_busy() isn't changed to update hctx->dispatch_busy in that commit, so fix the issue by updating hctx->dispatch_busy in case of real scheduler. Reported-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Fixes: 6e6fcbc27e77 ("blk-mq: support batching dispatch in case of io") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210625020248.1630497-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-24blk: Fix lock inversion between ioc lock and bfqd lockJan Kara8-21/+41
Lockdep complains about lock inversion between ioc->lock and bfqd->lock: bfqd -> ioc: put_io_context+0x33/0x90 -> ioc->lock grabbed blk_mq_free_request+0x51/0x140 blk_put_request+0xe/0x10 blk_attempt_req_merge+0x1d/0x30 elv_attempt_insert_merge+0x56/0xa0 blk_mq_sched_try_insert_merge+0x4b/0x60 bfq_insert_requests+0x9e/0x18c0 -> bfqd->lock grabbed blk_mq_sched_insert_requests+0xd6/0x2b0 blk_mq_flush_plug_list+0x154/0x280 blk_finish_plug+0x40/0x60 ext4_writepages+0x696/0x1320 do_writepages+0x1c/0x80 __filemap_fdatawrite_range+0xd7/0x120 sync_file_range+0xac/0xf0 ioc->bfqd: bfq_exit_icq+0xa3/0xe0 -> bfqd->lock grabbed put_io_context_active+0x78/0xb0 -> ioc->lock grabbed exit_io_context+0x48/0x50 do_exit+0x7e9/0xdd0 do_group_exit+0x54/0xc0 To avoid this inversion we change blk_mq_sched_try_insert_merge() to not free the merged request but rather leave that upto the caller similarly to blk_mq_sched_try_merge(). And in bfq_insert_requests() we make sure to free all the merged requests after dropping bfqd->lock. Fixes: aee69d78dec0 ("block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler") Reviewed-by: Ming Lei <ming.lei@redhat.com> Acked-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210623093634.27879-3-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-24bfq: Remove merged request already in bfq_requests_merged()Jan Kara1-28/+13
Currently, bfq does very little in bfq_requests_merged() and handles all the request cleanup in bfq_finish_requeue_request() called from blk_mq_free_request(). That is currently safe only because blk_mq_free_request() is called shortly after bfq_requests_merged() while bfqd->lock is still held. However to fix a lock inversion between bfqd->lock and ioc->lock, we need to call blk_mq_free_request() after dropping bfqd->lock. That would mean that already merged request could be seen by other processes inside bfq queues and possibly dispatched to the device which is wrong. So move cleanup of the request from bfq_finish_requeue_request() to bfq_requests_merged(). Acked-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210623093634.27879-2-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-24block: pass a gendisk to bdev_disk_changedChristoph Hellwig1-12/+10
bdev_disk_changed can only operate on whole devices. Make that clear by passing a gendisk instead of the struct block_device. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210624123240.441814-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-24block: move bdev_disk_changedChristoph Hellwig1-1/+54
Move bdev_disk_changed to block/partitions/core.c, together with the rest of the partition scanning code. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210624123240.441814-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-24block: add the events* attributes to disk_attrsChristoph Hellwig3-19/+10
Add the events attributes to the disk_attrs array, which ensures they are added by the driver core when the device is created rather than adding them after the device has been added, which is racy versus uevents and requires more boilerplate code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20210624073843.251178-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-24block: move the disk events code to a separate fileChristoph Hellwig4-493/+491
Move the code for handling disk events from genhd.c into a new file as it isn't very related to the rest of the file while at the same time requiring lots of forward declarations. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20210624073843.251178-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-24block: fix trace completion for chained bioEdward Hsieh1-7/+6
For chained bio, trace_block_bio_complete in bio_endio is currently called only by the parent bio once upon all chained bio completed. However, the sector and size for the parent bio are modified in bio_split. Therefore, the size and sector of the complete events might not match the queue events in blktrace. The original fix of bio completion trace <fbbaf700e7b1> ("block: trace completion of all bios.") wants multiple complete events to correspond to one queue event but missed this. The issue can be reproduced by md/raid5 read with bio cross chunks. To fix, move trace completion into the loop for every chained bio to call. Fixes: fbbaf700e7b1 ("block: trace completion of all bios.") Reviewed-by: Wade Liang <wadel@synology.com> Reviewed-by: BingJing Chang <bingjingc@synology.com> Signed-off-by: Edward Hsieh <edwardh@synology.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210624123030.27014-1-edwardh@synology.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-21block/partitions/msdos: Fix typo inidicator -> indicatorThomas Bracht Laumann Jespersen1-1/+1
Just a fix for a small typo in msdos_partition(). Signed-off-by: Thomas Bracht Laumann Jespersen <t@laumann.xyz> Link: https://lore.kernel.org/r/20210619195130.19348-1-t@laumann.xyz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-21block, bfq: reset waker pointer with shared queuesPaolo Valente1-2/+4
Commit 85686d0dc194 ("block, bfq: keep shared queues out of the waker mechanism") leaves shared bfq_queues out of the waker-detection mechanism. It attains this goal by not updating the pointer last_completed_rq_bfqq, if the last request completed belongs to a shared bfq_queue (so that the pointer will not point to the shared bfq_queue). Yet this has a side effect: the pointer last_completed_rq_bfqq keeps pointing, deceptively, to a bfq_queue that actually is not the last one to have had a request completed. As a consequence, such a bfq_queue may deceptively be considered as a waker of some bfq_queue, even of some shared bfq_queue. To address this issue, reset last_completed_rq_bfqq if the last request completed belongs to a shared queue. Fixes: 85686d0dc194 ("block, bfq: keep shared queues out of the waker mechanism") Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Link: https://lore.kernel.org/r/20210619140948.98712-8-paolo.valente@linaro.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-21block, bfq: check waker only for queues with no in-flight I/OPaolo Valente1-8/+13
Consider two bfq_queues, say Q1 and Q2, with Q2 empty. If a request of Q1 gets completed shortly before a new request arrives for Q2, then BFQ flags Q1 as a candidate waker for Q2. Yet, the arrival of this new request may have a different cause, in the following case. If also Q2 has requests in flight while waiting for the arrival of a new request, then the completion of its own requests may be the actual cause of the awakening of the process that sends I/O to Q2. So Q1 may be flagged wrongly as a candidate waker. This commit avoids this deceptive flagging, by disabling candidate-waker flagging for Q2, if Q2 has in-flight I/O. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Link: https://lore.kernel.org/r/20210619140948.98712-7-paolo.valente@linaro.org Signed-off-by: Jens Axboe <axboe@kernel.dk>