syzbot

INFO: task bch-copygc/loop:5249 blocked for more than 143 seconds.
      Not tainted 6.11.0-syzkaller-11993-g3efc57369a0c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:bch-copygc/loop state:D stack:20112 pid:5249  tgid:5249  ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5315 [inline]
 __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675
 __schedule_loop kernel/sched/core.c:6752 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6767
 __closure_sync+0x259/0x2f0 lib/closure.c:146
 bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:239 [inline]
 __bch2_write+0x56ad/0x5e30 fs/bcachefs/io_write.c:1504
 bch2_write+0x9b5/0x1760 fs/bcachefs/io_write.c:1634
 closure_queue include/linux/closure.h:270 [inline]
 closure_call include/linux/closure.h:432 [inline]
 bch2_data_update_read_done+0x22e/0x330 fs/bcachefs/data_update.c:423
 move_write fs/bcachefs/move.c:133 [inline]
 bch2_moving_ctxt_do_pending_writes+0x44c/0x8d0 fs/bcachefs/move.c:164
 move_buckets_wait+0x2ba/0x1290 fs/bcachefs/movinggc.c:114
 bch2_copygc_thread+0x83f/0xc20 fs/bcachefs/movinggc.c:386
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701
1 lock held by klogd/4666:
 #0: ffff8880b863ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:593
2 locks held by getty/4981:
 #0: ffff88814bb2c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
1 lock held by syz-executor169/6034:
 #0: ffff8880b863ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:593

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-11993-g3efc57369a0c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xff4/0x1040 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6035 Comm: syz-executor169 Not tainted 6.11.0-syzkaller-11993-g3efc57369a0c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x86/0x290 mm/kasan/generic.c:189
Code: 00 fc ff df 4f 8d 3c 31 4c 89 fd 4c 29 dd 48 83 fd 10 7f 29 48 85 ed 0f 84 3e 01 00 00 4c 89 cd 48 f7 d5 48 01 dd 41 80 3b 00 <0f> 85 c9 01 00 00 49 ff c3 48 ff c5 75 ee e9 1e 01 00 00 45 89 dc
RSP: 0000:ffffc90004aafcd0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffff11005ac1cd9 RCX: ffffffff816f7ac6
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88802d60e6c8
RBP: ffffffffffffffff R08: ffff88802d60e6cf R09: 1ffff11005ac1cd9
R10: dffffc0000000000 R11: ffffed1005ac1cd9 R12: 1ffff11005ac1cd9
R13: dffffc0000000000 R14: dffffc0000000001 R15: ffffed1005ac1cda
FS:  0000555574094380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f71beeb8000 CR3: 00000000295f0000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 instrument_atomic_write include/linux/instrumented.h:82 [inline]
 atomic_long_set include/linux/atomic/atomic-instrumented.h:3223 [inline]
 __rwsem_set_reader_owned kernel/locking/rwsem.c:176 [inline]
 rwsem_set_reader_owned kernel/locking/rwsem.c:181 [inline]
 __down_read_trylock kernel/locking/rwsem.c:1288 [inline]
 down_read_trylock+0x1f6/0x3c0 kernel/locking/rwsem.c:1565
 vma_start_read include/linux/mm.h:704 [inline]
 lock_vma_under_rcu+0x34b/0x790 mm/memory.c:6228
 do_user_addr_fault arch/x86/mm/fault.c:1329 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x17b/0x8c0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f71c6f1fcb6
Code: f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 <47> 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01
RSP: 002b:00007ffffde79600 EFLAGS: 00010206
RAX: 00000000004b8001 RBX: 00007ffffde796a0 RCX: 000000000000007f
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007ffffde79740
RBP: 0000000000000102 R08: 00007f71bea00000 R09: 00000000004b8000
R10: 0000000000000000 R11: 00007ffffde796b0 R12: 0000000000000001
R13: 00007f71c6fa2da0 R14: 0000000000000000 R15: 00007ffffde79740
 </TASK>