Hello, syzbot found the following issue on: HEAD commit: ad1b832bf1cf Merge tag 'devicetree-fixes-for-6.14-1' of gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1251a898580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e55cabe422b4fcaf dashboard link: https://syzkaller.appspot.com/bug?extid=5984e31a805252b3b40a 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=170d57df980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12df35a4580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/9de6d97a8d34/disk-ad1b832b.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/258463d6a9b5/vmlinux-ad1b832b.xz kernel image: https://storage.googleapis.com/syzbot-assets/f0449b94f00a/bzImage-ad1b832b.xz The issue was bisected to: commit 7ba167c4c73ed96eb002c98a9d7d49317dfb0191 Author: David Howells <dhowells@xxxxxxxxxx> Date: Mon Mar 18 16:57:31 2024 +0000 netfs: Switch to using unsigned long long rather than loff_t bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=166625b0580000 final oops: https://syzkaller.appspot.com/x/report.txt?x=156625b0580000 console output: https://syzkaller.appspot.com/x/log.txt?x=116625b0580000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+5984e31a805252b3b40a@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 7ba167c4c73e ("netfs: Switch to using unsigned long long rather than loff_t") INFO: task kworker/1:2:837 blocked for more than 143 seconds. Not tainted 6.14.0-rc2-syzkaller-00303-gad1b832bf1cf #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:2 state:D stack:25360 pid:837 tgid:837 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events p9_write_work Call Trace: <TASK> context_switch kernel/sched/core.c:5377 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 pipe_write+0x1c6/0x1a30 fs/pipe.c:456 __kernel_write_iter+0x433/0x950 fs/read_write.c:612 __kernel_write fs/read_write.c:632 [inline] kernel_write+0x214/0x330 fs/read_write.c:653 p9_fd_write net/9p/trans_fd.c:432 [inline] p9_write_work+0x57d/0xd70 net/9p/trans_fd.c:483 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 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: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 3 locks held by kworker/1:2/837: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc90003547c60 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90003547c60 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffff8880233c5468 (&pipe->mutex){+.+.}-{4:4}, at: pipe_write+0x1c6/0x1a30 fs/pipe.c:456 2 locks held by getty/5577: #0: ffff8880354a20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 2 locks held by syz-executor138/5815: #0: ffff8880233c5468 (&pipe->mutex){+.+.}-{4:4}, at: pipe_write+0x1c6/0x1a30 fs/pipe.c:456 #1: ffff888077e802e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:932 [inline] #1: ffff888077e802e8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_unbounded+0x156/0x820 mm/readahead.c:229 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc2-syzkaller-00303-gad1b832bf1cf #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
