Message-ID: <680a71ac.050a0220.317436.004e.GAE@google.com>
Date: Thu, 24 Apr 2025 10:15:24 -0700
From: syzbot <syzbot+d05837bec7673c4a18fe@...kaller.appspotmail.com>
To: chao@...nel.org, edumazet@...gle.com, jaegeuk@...nel.org, 
	linux-f2fs-devel@...ts.sourceforge.net, linux-kernel@...r.kernel.org, 
	sven@...fation.org, sw@...onwunderlich.de, syzkaller-bugs@...glegroups.com
Subject: [syzbot] [f2fs?] INFO: task hung in f2fs_fallocate (5)

Hello,

syzbot found the following issue on:

HEAD commit:    119009db2674 Merge tag 'vfs-6.15-rc3.fixes.2' of git://git..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12114c70580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a6bd70427e8b567f
dashboard link: https://syzkaller.appspot.com/bug?extid=d05837bec7673c4a18fe
compiler:       Debian clang version 15.0.6, Debian LLD 15.0.6
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=168cc63f980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17ccfbac580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2c746991d9a8/disk-119009db.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7dc89ed0561e/vmlinux-119009db.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4412f446b5ee/bzImage-119009db.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/ba3c3860bd1a/mount_0.gz
  fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=128cc63f980000)

The issue was bisected to:

commit 00b35530811f2aa3d7ceec2dbada80861c7632a8
Author: Eric Dumazet <edumazet@...gle.com>
Date:   Thu Feb 6 14:04:22 2025 +0000

    batman-adv: adopt netdev_hold() / netdev_put()

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=11aa263f980000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=13aa263f980000
console output: https://syzkaller.appspot.com/x/log.txt?x=15aa263f980000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d05837bec7673c4a18fe@...kaller.appspotmail.com
Fixes: 00b35530811f ("batman-adv: adopt netdev_hold() / netdev_put()")

INFO: task syz-executor529:5852 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor529 state:D stack:27024 pid:5852  tgid:5847  ppid:5846   task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x163/0x360 kernel/sched/core.c:6860
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
 rwsem_down_write_slowpath+0xedd/0x1420 kernel/locking/rwsem.c:1176
 __down_write_common kernel/locking/rwsem.c:1304 [inline]
 __down_write kernel/locking/rwsem.c:1313 [inline]
 down_write+0x1da/0x220 kernel/locking/rwsem.c:1578
 inode_lock include/linux/fs.h:867 [inline]
 f2fs_fallocate+0x26d/0xa10 fs/f2fs/file.c:1940
 vfs_fallocate+0x627/0x7a0 fs/open.c:338
 file_ioctl fs/ioctl.c:-1 [inline]
 do_vfs_ioctl+0x2057/0x2750 fs/ioctl.c:885
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0x80/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55dfb43589
RSP: 002b:00007f55dfad7218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f55dfbcf618 RCX: 00007f55dfb43589
RDX: 0000200000000000 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00007f55dfbcf610 R08: 00007ffec02c2d87 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f55dfb9c6f0
R13: 0000200000000140 R14: 0000200000000020 R15: 0000200000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764
1 lock held by syslogd/5183:
2 locks held by getty/5583:
 #0: ffff88814d6370a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222
5 locks held by syz-executor529/5849:
2 locks held by syz-executor529/5852:
 #0: ffff888036082420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
 #0: ffff888036082420 (sb_writers#8){.+.+}-{0:0}, at: vfs_fallocate+0x5a1/0x7a0 fs/open.c:337
 #1: ffff888079270a38 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #1: ffff888079270a38 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: f2fs_fallocate+0x26d/0xa10 fs/f2fs/file.c:1940

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
 watchdog+0x1058/0x10a0 kernel/hung_task.c:437
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5849 Comm: syz-executor529 Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:check_preemption_disabled+0x6a/0x120 lib/smp_processor_id.c:19
Code: 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 <74> c7 49 89 f6 49 89 ff 65 4c 8b 2c 25 08 10 65 93 41 f6 45 2f 04
RSP: 0018:ffffc90003f5f2d8 EFLAGS: 00000046
RAX: 0000000080000000 RBX: 0000000000000000 RCX: ffff888030afbc00
RDX: 0000000000000000 RSI: ffffffff8e4c7ff1 RDI: ffffffff8ca0e180
RBP: ffffffff93651020 R08: ffff88807c6bc34f R09: 1ffff1100f8d7869
R10: dffffc0000000000 R11: ffffed100f8d786a R12: ffffffff93651020
R13: 0000000000000246 R14: 00000000ffffffff R15: ffffffff8ed3df80
FS:  00007f55dfaf86c0(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff2eb77468 CR3: 0000000027afe000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lockdep_recursion_finish kernel/locking/lockdep.c:472 [inline]
 lock_is_held_type+0x112/0x1a0 kernel/locking/lockdep.c:5939
 lock_is_held include/linux/lockdep.h:249 [inline]
 __might_resched+0xa8/0x6c0 kernel/sched/core.c:8780
 down_read+0x90/0xa50 kernel/locking/rwsem.c:1523
 f2fs_down_read fs/f2fs/f2fs.h:2197 [inline]
 f2fs_allocate_new_section fs/f2fs/segment.c:3293 [inline]
 f2fs_allocate_pinning_section+0xac/0x4e0 fs/f2fs/segment.c:3309
 f2fs_expand_inode_data+0x6ed/0xde0 fs/f2fs/file.c:1865
 f2fs_fallocate+0x537/0xa10 fs/f2fs/file.c:1975
 vfs_fallocate+0x627/0x7a0 fs/open.c:338
 file_ioctl fs/ioctl.c:-1 [inline]
 do_vfs_ioctl+0x2057/0x2750 fs/ioctl.c:885
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0x80/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55dfb43589
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f55dfaf8218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f55dfbcf608 RCX: 00007f55dfb43589
RDX: 0000200000000140 RSI: 0000000040305828 RDI: 0000000000000005
RBP: 00007f55dfbcf600 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f55dfb9c6f0
R13: 0000200000000140 R14: 0000200000000020 R15: 0000200000000000
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.186 msecs


---
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@...glegroups.com.

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

Powered by blists - more mailing lists