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INFO: task hung in bch2_rebalance_stop (2)

Status: auto-obsoleted due to no activity on 2025/04/28 01:42
Subsystems: kernel
[Documentation on labels]
First crash: 185d, last: 185d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in bch2_rebalance_stop bcachefs 1 17 354d 420d 0/29 auto-obsoleted due to no activity on 2024/10/07 10:10

Sample crash report:
INFO: task syz-executor:6415 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc7-syzkaller-g1950a0af2d55 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:6415  tgid:6415  ppid:1      flags:0x00000009
Call trace:
 __switch_to+0x414/0x788 arch/arm64/kernel/process.c:701 (T)
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1744/0x27f0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0xbc/0x238 kernel/sched/core.c:6848
 schedule_timeout+0xb4/0x290 kernel/time/sleep_timeout.c:75
 do_wait_for_common+0x30c/0x468 kernel/sched/completion.c:95
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:148
 kthread_stop+0x1b8/0x714 kernel/kthread.c:712
 bch2_rebalance_stop+0xc4/0xf4 fs/bcachefs/rebalance.c:459
 __bch2_fs_read_only+0x54/0x3e4 fs/bcachefs/super.c:264
 bch2_fs_read_only+0x930/0xf00 fs/bcachefs/super.c:356
 __bch2_fs_stop+0x104/0x570 fs/bcachefs/super.c:621
 bch2_put_super+0x40/0x50 fs/bcachefs/fs.c:2050
 generic_shutdown_super+0x12c/0x2bc fs/super.c:642
 bch2_kill_sb+0x40/0x58 fs/bcachefs/fs.c:2278
 deactivate_locked_super+0xc4/0x12c fs/super.c:473
 deactivate_super+0xe0/0x100 fs/super.c:506
 cleanup_mnt+0x34c/0x3dc fs/namespace.c:1373
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1380
 task_work_run+0x230/0x2e0 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 do_notify_resume+0x178/0x1f4 arch/arm64/kernel/entry-common.c:151
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline]
 el0_svc+0xac/0x168 arch/arm64/kernel/entry-common.c:745
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
INFO: task bch-rebalance/l:7488 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc7-syzkaller-g1950a0af2d55 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:bch-rebalance/l state:D stack:0     pid:7488  tgid:7488  ppid:2      flags:0x00000048
Call trace:
 __switch_to+0x414/0x788 arch/arm64/kernel/process.c:701 (T)
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1744/0x27f0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0xbc/0x238 kernel/sched/core.c:6848
 bch2_move_ratelimit+0x8e0/0xbd8 fs/bcachefs/move.c:492
 do_rebalance+0xa44/0xeb4 fs/bcachefs/rebalance.c:340
 bch2_rebalance_thread+0xcc/0x140 fs/bcachefs/rebalance.c:401
 kthread+0x288/0x310 kernel/kthread.c:389
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862

Showing all locks held in the system:
3 locks held by kworker/u8:0/11:
3 locks held by ksoftirqd/0/16:
1 lock held by khungtaskd/31:
 #0: ffff80008fb83160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:336
3 locks held by kworker/u8:2/41:
 #0: ffff0000c0031148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3210
 #1: ffff8000990c7c20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3210
 #2: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
4 locks held by kworker/u8:3/44:
 #0: ffff000103b16148 ((wq_completion)btree_update){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3210
 #1: ffff8000990f7c20 ((work_completion)(&c->btree_interior_update_work)){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3210
 #2: ffff000103604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:157
 #3: ffff0001036266d0 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x588/0x15ac fs/bcachefs/btree_update_interior.c:1197
3 locks held by kworker/u8:5/568:
 #0: ffff0000c32b3148 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3210
 #1: ffff80009ccd7c20 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3210
 #2: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
4 locks held by kworker/u9:1/5984:
 #0: ffff00010391f948 ((wq_completion)bcachefs){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3210
 #1: ffff80009d6f7c20 ((work_completion)(&wp->index_update_work)){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3210
 #2: ffff000103604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:157
 #3: ffff0001036266d0 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x588/0x15ac fs/bcachefs/btree_update_interior.c:1197
1 lock held by klogd/6020:
1 lock held by dhcpcd/6085:
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline]
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xb30/0x1adc net/core/rtnetlink.c:4011
2 locks held by getty/6180:
 #0: ffff0000d25450a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009b9ee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41c/0x1228 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/6415:
 #0: ffff0000fed7a0e0 (&type->s_umount_key#58){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff0000fed7a0e0 (&type->s_umount_key#58){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff0000fed7a0e0 (&type->s_umount_key#58){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:505
 #1: ffff000103600278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xfc/0x570 fs/bcachefs/super.c:620
3 locks held by kworker/u8:7/6483:
 #0: ffff0000c0031948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3210
 #1: ffff8000a0e97c20 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3210
 #2: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
6 locks held by kworker/u8:8/6512:
 #0: ffff0000c1899948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3210
 #1: ffff8000a2c97c20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3210
 #2: ffff8000928c3910 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x13c/0xa34 net/core/net_namespace.c:602
 #3: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
 #4: ffff0000ce970768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: wiphy_lock include/net/cfg80211.h:6019 [inline]
 #4: ffff0000ce970768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x12c/0x5dc net/mac80211/iface.c:2282
 #5: ffff80008fa1fc10 (cpu_hotplug_lock){++++}-{0:0}, at: flush_all_backlogs net/core/dev.c:6063 [inline]
 #5: ffff80008fa1fc10 (cpu_hotplug_lock){++++}-{0:0}, at: unregister_netdevice_many_notify+0x518/0x1c6c net/core/dev.c:11526
3 locks held by kworker/u8:10/6832:
 #0: ffff0000d1dbb148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3210
 #1: ffff8000a07f7c20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3210
 #2: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
4 locks held by bch-reclaim/loo/7486:
 #0: ffff00010364b0a8 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x144/0x4b8 fs/bcachefs/journal_reclaim.c:739
 #1: ffff000103604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:157
 #2: ffff000103604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire+0x18/0x54 include/linux/srcu.h:157
 #3: ffff0001036266d0 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x588/0x15ac fs/bcachefs/btree_update_interior.c:1197
1 lock held by syz-executor/7678:
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
1 lock held by syz-executor/7683:
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
2 locks held by syz-executor/7714:
 #0: ffff8000928c3910 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x290/0x4ac net/core/net_namespace.c:512
 #1: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
2 locks held by syz-executor/7725:
 #0: ffff8000928c3910 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x290/0x4ac net/core/net_namespace.c:512
 #1: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
2 locks held by syz-executor/7726:
 #0: ffff8000928c3910 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x290/0x4ac net/core/net_namespace.c:512
 #1: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79
1 lock held by syz-executor/7762:
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline]
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xb30/0x1adc net/core/rtnetlink.c:4011
1 lock held by syz-executor/7769:
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline]
 #0: ffff8000928cfca8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xb30/0x1adc net/core/rtnetlink.c:4011

=============================================


Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/28 01:36 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 18070896 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in bch2_rebalance_stop
* Struck through repros no longer work on HEAD.