INFO: task syz-executor.2:29929 blocked for more than 143 seconds.
      Not tainted 6.0.0-rc6-next-20220923-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:25496 pid:29929 ppid:3625   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5194 [inline]
 __schedule+0xbd2/0x55b0 kernel/sched/core.c:6506
 schedule+0xda/0x1b0 kernel/sched/core.c:6582
 wb_wait_for_completion+0x17e/0x240 fs/fs-writeback.c:191
 __writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2607
 try_to_writeback_inodes_sb+0x94/0xc0 fs/fs-writeback.c:2655
 ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2943
 ext4_da_write_begin+0x16c/0xb50 fs/ext4/inode.c:2970
 generic_perform_write+0x252/0x570 mm/filemap.c:3753
 ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:285
 ext4_file_write_iter+0x8b8/0x1740 fs/ext4/file.c:694
 __kernel_write+0x2c6/0x7c0 fs/read_write.c:523
 __dump_emit+0x194/0x280 fs/coredump.c:809
 dump_emit+0x349/0x4b0 fs/coredump.c:846
 dump_user_range+0x8b/0x3c0 fs/coredump.c:883
 elf_core_dump+0x26de/0x3510 fs/binfmt_elf.c:2311
 do_coredump+0x26d7/0x3c20 fs/coredump.c:760
 get_signal+0x1be6/0x2430 kernel/signal.c:2844
 arch_do_signal_or_restart+0x82/0x2300 arch/x86/kernel/signal.c:869
 exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
 exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:309
 asm_exc_general_protection+0x22/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fded788a5b1
RSP: 002b:0000000020000510 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fded79abf80 RCX: 00007fded788a5a9
RDX: 0000000020000540 RSI: 0000000020000510 RDI: 0000000000020000
RBP: 00007fded78e5580 R08: 00000000200005c0 R09: 00000000200005c0
R10: 0000000020000580 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fffa731b61f R14: 00007fded8a82300 R15: 0000000000022000
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.0.0-rc6-next-20220923-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x24/0x18a lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x32f/0x3c0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xc6b/0xfc0 kernel/hung_task.c:369
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 42 Comm: kworker/u4:2 Not tainted 6.0.0-rc6-next-20220923-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:__rb_erase_augmented include/linux/rbtree_augmented.h:201 [inline]
RIP: 0010:rb_erase+0x0/0x1210 lib/rbtree.c:443
Code: 08 4c 8b 04 24 e9 1f f6 ff ff e8 8b 0a 86 f8 48 8b 54 24 08 4c 8b 04 24 e9 f7 f5 ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 <48> b8 00 00 00 00 00 fc ff df 41 57 49 89 f7 41 56 41 55 49 89 fd
RSP: 0018:ffffc90000b37930 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff88801865bb00 RCX: 1ffff11004051009
RDX: dffffc0000000000 RSI: ffff888020288040 RDI: ffff88801865bb10
RBP: ffff888020288000 R08: ffff888020288000 R09: ffffffff8de06717
R10: 0000000000000000 R11: 0000000000000008 R12: ffff88801865bb10
R13: ffff888020288170 R14: ffff888020288048 R15: ffff888020288040
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa88a30b803 CR3: 000000000bc8e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rb_erase_cached include/linux/rbtree.h:126 [inline]
 __dequeue_entity kernel/sched/fair.c:635 [inline]
 set_next_entity+0x32d/0x5d0 kernel/sched/fair.c:4799
 pick_next_task_fair+0x8c5/0x12e0 kernel/sched/fair.c:7604
 __pick_next_task kernel/sched/core.c:5816 [inline]
 pick_next_task kernel/sched/core.c:5891 [inline]
 __schedule+0x468/0x55b0 kernel/sched/core.c:6470
 schedule+0xda/0x1b0 kernel/sched/core.c:6582
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1935
 toggle_allocation_gate mm/kfence/core.c:807 [inline]
 toggle_allocation_gate+0x305/0x390 mm/kfence/core.c:792
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>