Hello, syzbot found the following issue on: HEAD commit: f03359bca01b Merge tag 'for-6.9-rc6-tag' of git://git.kern.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=1298e660980000 kernel config: https://syzkaller.appspot.com/x/.config?x=d2f00edef461175 dashboard link: https://syzkaller.appspot.com/bug?extid=7bf808f7fe4a6549f36e compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12a7c31f180000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16109450980000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/e3ee5200440e/disk-f03359bc.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c651e70b4ae3/vmlinux-f03359bc.xz kernel image: https://storage.googleapis.com/syzbot-assets/196f43b316ad/bzImage-f03359bc.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/883314a64ffe/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7bf808f7fe4a6549f36e@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task syz-executor334:5078 blocked for more than 143 seconds. Not tainted 6.9.0-rc6-syzkaller-00131-gf03359bca01b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor334 state:D stack:15856 pid:5078 tgid:5078 ppid:5075 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1796/0x4a00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6838 __closure_sync+0x259/0x2f0 lib/closure.c:135 closure_sync include/linux/closure.h:194 [inline] __bch2_write+0x5458/0x5bd0 fs/bcachefs/io_write.c:1486 bch2_write+0x947/0x1590 fs/bcachefs/io_write.c:1610 closure_queue include/linux/closure.h:257 [inline] closure_call include/linux/closure.h:390 [inline] bch2_dio_write_loop fs/bcachefs/fs-io-direct.c:531 [inline] bch2_direct_write+0x1a52/0x3050 fs/bcachefs/fs-io-direct.c:652 bch2_write_iter+0x206/0x2840 fs/bcachefs/fs-io-buffered.c:1143 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa84/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f42713dfdf9 RSP: 002b:00007ffdf34d9c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f42713dfdf9 RDX: 00000000175d9003 RSI: 0000000020000200 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000555500000000 R09: 0000555500000000 R10: 0000555500000000 R11: 0000000000000246 R12: 00000000000f4240 R13: 00007ffdf34d9ec8 R14: 0000000000000001 R15: 00007ffdf34d9c90 </TASK> Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 1 lock held by kworker/u8:3/50: #0: ffff8880b953e658 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 2 locks held by getty/4827: #0: ffff88802aba90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f162f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by syz-executor334/5078: #0: ffff8880730de420 (sb_writers#9){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2855 [inline] #0: ffff8880730de420 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff8880779f88b8 (&sb->s_type->i_mutex_key#16){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:795 [inline] #1: ffff8880779f88b8 (&sb->s_type->i_mutex_key#16){+.+.}-{3:3}, at: bch2_direct_write+0x243/0x3050 fs/bcachefs/fs-io-direct.c:598 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.9.0-rc6-syzkaller-00131-gf03359bca01b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfde/0x1020 kernel/hung_task.c:380 kthread+0x2f0/0x390 kernel/kthread.c:388 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 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112 --- This report is generated by a bot. 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