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Li Nan 8d21155467 blk-iocost: use spin_lock_irqsave in adjust_inuse_and_calc_cost
adjust_inuse_and_calc_cost() use spin_lock_irq() and IRQ will be enabled
when unlock. DEADLOCK might happen if we have held other locks and disabled
IRQ before invoking it.

Fix it by using spin_lock_irqsave() instead, which can keep IRQ state
consistent with before when unlock.

  ================================
  WARNING: inconsistent lock state
  5.10.0-02758-g8e5f91fd772f #26 Not tainted
  --------------------------------
  inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
  kworker/2:3/388 [HC0[0]:SC0[0]:HE0:SE1] takes:
  ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: spin_lock_irq
  ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: bfq_bio_merge+0x141/0x390
  {IN-HARDIRQ-W} state was registered at:
    __lock_acquire+0x3d7/0x1070
    lock_acquire+0x197/0x4a0
    __raw_spin_lock_irqsave
    _raw_spin_lock_irqsave+0x3b/0x60
    bfq_idle_slice_timer_body
    bfq_idle_slice_timer+0x53/0x1d0
    __run_hrtimer+0x477/0xa70
    __hrtimer_run_queues+0x1c6/0x2d0
    hrtimer_interrupt+0x302/0x9e0
    local_apic_timer_interrupt
    __sysvec_apic_timer_interrupt+0xfd/0x420
    run_sysvec_on_irqstack_cond
    sysvec_apic_timer_interrupt+0x46/0xa0
    asm_sysvec_apic_timer_interrupt+0x12/0x20
  irq event stamp: 837522
  hardirqs last  enabled at (837521): [<ffffffff84b9419d>] __raw_spin_unlock_irqrestore
  hardirqs last  enabled at (837521): [<ffffffff84b9419d>] _raw_spin_unlock_irqrestore+0x3d/0x40
  hardirqs last disabled at (837522): [<ffffffff84b93fa3>] __raw_spin_lock_irq
  hardirqs last disabled at (837522): [<ffffffff84b93fa3>] _raw_spin_lock_irq+0x43/0x50
  softirqs last  enabled at (835852): [<ffffffff84e00558>] __do_softirq+0x558/0x8ec
  softirqs last disabled at (835845): [<ffffffff84c010ff>] asm_call_irq_on_stack+0xf/0x20

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(&bfqd->lock);
    <Interrupt>
      lock(&bfqd->lock);

   *** DEADLOCK ***

  3 locks held by kworker/2:3/388:
   #0: ffff888107af0f38 ((wq_completion)kthrotld){+.+.}-{0:0}, at: process_one_work+0x742/0x13f0
   #1: ffff8881176bfdd8 ((work_completion)(&td->dispatch_work)){+.+.}-{0:0}, at: process_one_work+0x777/0x13f0
   #2: ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: spin_lock_irq
   #2: ffff888118c00c28 (&bfqd->lock){?.-.}-{2:2}, at: bfq_bio_merge+0x141/0x390

  stack backtrace:
  CPU: 2 PID: 388 Comm: kworker/2:3 Not tainted 5.10.0-02758-g8e5f91fd772f #26
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  Workqueue: kthrotld blk_throtl_dispatch_work_fn
  Call Trace:
   __dump_stack lib/dump_stack.c:77 [inline]
   dump_stack+0x107/0x167
   print_usage_bug
   valid_state
   mark_lock_irq.cold+0x32/0x3a
   mark_lock+0x693/0xbc0
   mark_held_locks+0x9e/0xe0
   __trace_hardirqs_on_caller
   lockdep_hardirqs_on_prepare.part.0+0x151/0x360
   trace_hardirqs_on+0x5b/0x180
   __raw_spin_unlock_irq
   _raw_spin_unlock_irq+0x24/0x40
   spin_unlock_irq
   adjust_inuse_and_calc_cost+0x4fb/0x970
   ioc_rqos_merge+0x277/0x740
   __rq_qos_merge+0x62/0xb0
   rq_qos_merge
   bio_attempt_back_merge+0x12c/0x4a0
   blk_mq_sched_try_merge+0x1b6/0x4d0
   bfq_bio_merge+0x24a/0x390
   __blk_mq_sched_bio_merge+0xa6/0x460
   blk_mq_sched_bio_merge
   blk_mq_submit_bio+0x2e7/0x1ee0
   __submit_bio_noacct_mq+0x175/0x3b0
   submit_bio_noacct+0x1fb/0x270
   blk_throtl_dispatch_work_fn+0x1ef/0x2b0
   process_one_work+0x83e/0x13f0
   process_scheduled_works
   worker_thread+0x7e3/0xd80
   kthread+0x353/0x470
   ret_from_fork+0x1f/0x30

Fixes: b0853ab4a2 ("blk-iocost: revamp in-period donation snapbacks")
Signed-off-by: Li Nan <linan122@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20230527091904.3001833-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-05 12:08:32 -06:00
Documentation block: move the code to do early boot lookup of block devices to block/ 2023-06-05 10:57:40 -06:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
arch init: remove pointless Root_* values 2023-06-05 10:55:20 -06:00
block blk-iocost: use spin_lock_irqsave in adjust_inuse_and_calc_cost 2023-06-05 12:08:32 -06:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto This push fixes the following problems: 2023-05-07 10:57:14 -07:00
drivers mtd: block2mtd: don't call early_lookup_bdev after the system is running 2023-06-05 11:10:14 -06:00
fs init: improve the name_to_dev_t interface 2023-06-05 10:56:46 -06:00
include block: mark early_lookup_bdev as __init 2023-06-05 11:10:14 -06:00
init block: move the code to do early boot lookup of block devices to block/ 2023-06-05 10:57:40 -06:00
io_uring for-6.4/io_uring-2023-05-07 2023-05-07 10:00:09 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel PM: hibernate: don't use early_lookup_bdev in resume_store 2023-06-05 10:57:40 -06:00
lib iov_iter: Kill ITER_PIPE 2023-05-24 08:42:17 -06:00
mm block: introduce holder ops 2023-06-05 10:53:04 -06:00
net net: Make sock_splice_read() use copy_splice_read() by default 2023-05-24 08:42:16 -06:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples LoongArch changes for v6.4 2023-05-04 12:40:16 -07:00
scripts Locking changes in v6.4: 2023-05-05 12:56:55 -07:00
security integrity-v6.4 2023-04-29 10:11:32 -07:00
sound sound fixes for 6.4-rc1 2023-05-06 08:07:11 -07:00
tools cxl fixes for v6.4-rc2 2023-05-14 12:32:34 -07:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt s390: 2023-05-01 12:06:20 -07:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap for-6.4/block-2023-05-06 2023-05-06 08:28:58 -07:00
.rustfmt.toml rust: add `.rustfmt.toml` 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS A handful of late-arriving documentation fixes, plus one Spanish 2023-05-05 13:16:42 -07:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Devicetree binding fixes for v6.4 2023-05-11 09:01:40 -05:00
Makefile Linux 6.4-rc2 2023-05-14 12:51:40 -07:00
README

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