INFO: task syz.0.73:6658 blocked for more than 143 seconds. Not tainted 6.15.0-rc3-syzkaller-00283-gf1a3944c860b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.73 state:D stack:27096 pid:6658 tgid:6592 ppid:5820 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:877 [inline] lookup_slow+0x46/0x70 fs/namei.c:1833 walk_component+0x2d2/0x400 fs/namei.c:2138 lookup_last fs/namei.c:2636 [inline] path_lookupat+0x163/0x430 fs/namei.c:2660 filename_lookup+0x212/0x570 fs/namei.c:2689 user_path_at+0x3a/0x60 fs/namei.c:3120 do_mount fs/namespace.c:4221 [inline] __do_sys_mount fs/namespace.c:4435 [inline] __se_sys_mount+0x2d3/0x410 fs/namespace.c:4412 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe50818e969 RSP: 002b:00007fe509037038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fe5083b6080 RCX: 00007fe50818e969 RDX: 0000200000000300 RSI: 00002000000002c0 RDI: 0000200000000100 RBP: 00007fe508210ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe5083b6080 R15: 00007ffddbce01a8 INFO: task bch-reclaim/loo:6651 blocked for more than 143 seconds. Not tainted 6.15.0-rc3-syzkaller-00283-gf1a3944c860b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:bch-reclaim/loo state:D stack:26856 pid:6651 tgid:6651 ppid:2 task_flags:0x200840 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 btree_write_buffer_flush_seq+0x1829/0x19a0 fs/bcachefs/btree_write_buffer.c:569 bch2_btree_write_buffer_journal_flush+0x69/0xb0 fs/bcachefs/btree_write_buffer.c:586 journal_flush_pins+0x8e0/0xe90 fs/bcachefs/journal_reclaim.c:592 __bch2_journal_reclaim+0x781/0xd10 fs/bcachefs/journal_reclaim.c:723 bch2_journal_reclaim_thread+0x177/0x4f0 fs/bcachefs/journal_reclaim.c:765 kthread+0x70e/0x8a0 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 Showing all locks held in the system: 6 locks held by kworker/u8:0/12: 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/u8:6/1154: #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90004207c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004207c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 1 lock held by dhcpcd/5484: #0: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x323/0x1b50 net/ipv4/devinet.c:1121 2 locks held by getty/5574: #0: ffff88814da930a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 5 locks held by syz.0.73/6593: #0: ffff888054470420 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff888057956400 (&sb->s_type->i_mutex_key#26){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff888057956400 (&sb->s_type->i_mutex_key#26){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline] #1: ffff888057956400 (&sb->s_type->i_mutex_key#26){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036 #2: ffff8880579567e8 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:567 #3: ffff88805a404228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff88805a404228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff88805a404228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3202 #4: ffff88805a426590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179 1 lock held by syz.0.73/6658: #0: ffff888057956400 (&sb->s_type->i_mutex_key#26){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #0: ffff888057956400 (&sb->s_type->i_mutex_key#26){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833 3 locks held by bch-reclaim/loo/6651: #0: ffff88805a44ad28 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x16b/0x4f0 fs/bcachefs/journal_reclaim.c:764 #1: ffff88805a404228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #1: ffff88805a404228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #1: ffff88805a404228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3385 #2: ffff88805a4045d0 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x1829/0x19a0 fs/bcachefs/btree_write_buffer.c:569 3 locks held by bch-copygc/loop/6652: #0: ffff88805a4045d0 (&wb->flushing.lock){+.+.}-{4:4}, at: bch2_btree_write_buffer_flush_nocheck_rw fs/bcachefs/btree_write_buffer.c:620 [inline] #0: ffff88805a4045d0 (&wb->flushing.lock){+.+.}-{4:4}, at: bch2_btree_write_buffer_tryflush+0x130/0x1a0 fs/bcachefs/btree_write_buffer.c:635 #1: ffff88805a404228 (&c->btree_trans_barrier){.+.+}-{0:0} , at: srcu_lock_acquire include/linux/srcu.h:161 [inline] , at: srcu_read_lock include/linux/srcu.h:253 [inline] , at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3202 #2: ffff88805a426590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179 2 locks held by syz-executor/8970: #0: ffffffff8f7ddc20 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8f7ddc20 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8f7ddc20 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064 2 locks held by syz.5.357/9031: 2 locks held by syz.7.359/9034: 5 locks held by syz.7.359/9059: 3 locks held by syz.0.360/9036: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00283-gf1a3944c860b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9059 Comm: syz.7.359 Not tainted 6.15.0-rc3-syzkaller-00283-gf1a3944c860b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409 Code: e8 be 50 89 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ff 1f e9 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07 RSP: 0018:ffffc90003575e30 EFLAGS: 00000002 RAX: 1ffffffff3362900 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 000000000000a2ee RDI: 000000000000a2ef RBP: ffffffff99b14c10 R08: ffff888024358237 R09: 1ffff1100486b046 R10: dffffc0000000000 R11: ffffffff85366ca0 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff99b14980 R15: 0000000000000000 FS: 00007f48f57f66c0(0000) GS:ffff888126103000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f808ff8 CR3: 000000007d2b2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:137 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline] wait_for_lsr+0x19e/0x2f0 drivers/tty/serial/8250/8250_port.c:2098 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline] serial8250_console_write+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3456 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xc4/0x270 kernel/printk/printk.c:3325 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450 _printk+0xcf/0x120 kernel/printk/printk.c:2475 __mlog_printk+0x25e/0x290 fs/ocfs2/cluster/masklog.c:77 ocfs2_block_check_validate+0x49f/0x5f0 fs/ocfs2/blockcheck.c:415 ocfs2_read_blocks+0x1002/0x1540 fs/ocfs2/buffer_head_io.c:382 ocfs2_read_quota_phys_block fs/ocfs2/quota_global.c:157 [inline] ocfs2_quota_read+0x2d8/0x910 fs/ocfs2/quota_global.c:199 read_blk fs/quota/quota_tree.c:61 [inline] find_tree_dqentry+0x1fb/0x1070 fs/quota/quota_tree.c:671 find_tree_dqentry+0x6c4/0x1070 fs/quota/quota_tree.c:698 find_tree_dqentry+0x6c4/0x1070 fs/quota/quota_tree.c:698 find_tree_dqentry+0x6c4/0x1070 fs/quota/quota_tree.c:698 find_tree_dqentry+0x6c4/0x1070 fs/quota/quota_tree.c:698 find_dqentry fs/quota/quota_tree.c:716 [inline] qtree_read_dquot+0x564/0x800 fs/quota/quota_tree.c:736 ocfs2_acquire_dquot+0x2f9/0xb30 fs/ocfs2/quota_global.c:838 dqget+0x7ae/0xf10 fs/quota/dquot.c:977 __dquot_initialize+0x3b3/0xcb0 fs/quota/dquot.c:1505 ocfs2_get_init_inode+0x13b/0x1b0 fs/ocfs2/namei.c:202 ocfs2_mknod+0x863/0x2050 fs/ocfs2/namei.c:310 ocfs2_create+0x1a5/0x440 fs/ocfs2/namei.c:673 lookup_open fs/namei.c:3701 [inline] open_last_lookups fs/namei.c:3800 [inline] path_openat+0x14f1/0x3830 fs/namei.c:4036 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f48f798e969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f48f57f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f48f7bb6160 RCX: 00007f48f798e969 RDX: 0000000000000042 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007f48f7a10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f48f7bb6160 R15: 00007ffd3627f678