INFO: task syz.3.74:6465 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.74 state:D stack:28232 pid:6465 tgid:6454 ppid:5829 task_flags:0x400040 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_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:867 [inline] open_last_lookups fs/namei.c:3797 [inline] path_openat+0x8da/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_creat fs/open.c:1522 [inline] __se_sys_creat fs/open.c:1516 [inline] __x64_sys_creat+0x8f/0xc0 fs/open.c:1516 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: 0033:0x7fa65af8e969 RSP: 002b:00007fa65bd40038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007fa65b1b6080 RCX: 00007fa65af8e969 RDX: 0000000000000000 RSI: 00000000000000b8 RDI: 00002000000067c0 RBP: 00007fa65b010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fa65b1b6080 R15: 00007fff3dd92c18 INFO: task syz.3.74:6468 blocked for more than 144 seconds. Not tainted 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.74 state:D stack:28872 pid:6468 tgid:6454 ppid:5829 task_flags:0x400040 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 fs/namei.c:2138 [inline] link_path_walk+0x925/0xe50 fs/namei.c:2503 path_openat+0x28c/0x3830 fs/namei.c:4035 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_creat fs/open.c:1522 [inline] __se_sys_creat fs/open.c:1516 [inline] __x64_sys_creat+0x8f/0xc0 fs/open.c:1516 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: 0033:0x7fa65af8e969 RSP: 002b:00007fa65bd1f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007fa65b1b6160 RCX: 00007fa65af8e969 RDX: 0000000000000000 RSI: 0000000000000187 RDI: 0000200000006900 RBP: 00007fa65b010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fa65b1b6160 R15: 00007fff3dd92c18 INFO: task syz.3.74:6469 blocked for more than 145 seconds. Not tainted 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.74 state:D stack:28952 pid:6469 tgid:6454 ppid:5829 task_flags:0x400040 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:4218 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount+0x2d3/0x410 fs/namespace.c:4409 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: 0033:0x7fa65af8e969 RSP: 002b:00007fa6589f4038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fa65b1b6240 RCX: 00007fa65af8e969 RDX: 0000200000000080 RSI: 0000200000000040 RDI: 0000000000000000 RBP: 00007fa65b010ab1 R08: 0000200000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa65b1b6240 R15: 00007fff3dd92c18 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: 5 locks held by kworker/u8:0/12: 1 lock held by khungtaskd/31: #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 4 locks held by kworker/u8:4/82: #0: ffff88801e6a4948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801e6a4948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90001557c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90001557c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff88807fdba0e0 (&type->s_umount_key#96){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562 #3: ffff8880574e2fe0 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102 2 locks held by kworker/u8:5/1334: 2 locks held by getty/5578: #0: ffff88814dd780a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900033532f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5819: #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 3 locks held by kworker/1:4/5866: 4 locks held by syz.3.74/6455: 2 locks held by syz.3.74/6465: #0: ffff88807fdba420 (sb_writers#29){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880574e3390 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff8880574e3390 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline] #1: ffff8880574e3390 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036 1 lock held by syz.3.74/6468: #0: ffff8880574e3390 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #0: ffff8880574e3390 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833 1 lock held by syz.3.74/6469: #0: ffff8880574e3390 (&type->i_mutex_dir_key #18){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #18){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833 1 lock held by syz-executor/6569: #0: ffff88805f0e60e0 (&type->s_umount_key#84){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88805f0e60e0 (&type->s_umount_key#84){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88805f0e60e0 (&type->s_umount_key#84){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 3 locks held by kworker/u8:10/7961: 2 locks held by syz.8.274/8441: #0: ffff88807fdba0e0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807fdba0e0 (&type->s_umount_key#96){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 #1: ffff88802508c7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff88802508c7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 1 lock held by udevadm/8684: 1 lock held by sed/8686: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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: 8645 Comm: syz.6.289 Not tainted 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:check_preemption_disabled+0x12/0x120 lib/smp_processor_id.c:13 Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 4e 0e 23 07 <48> 89 44 24 08 65 8b 05 56 0e 23 07 65 8b 0d 4b 0e 23 07 f7 c1 ff RSP: 0018:ffffc900049c7288 EFLAGS: 00000086 RAX: 0e80717f8706fb00 RBX: 0000000000000000 RCX: 0e80717f8706fb00 RDX: 0000000000000001 RSI: ffffffff8d924660 RDI: ffffffff8bc12000 RBP: ffffffff820fbac3 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff820fbac3 R12: 0000000000000002 R13: ffffffff8df3dce0 R14: 0000000000000000 R15: 0000000000000246 FS: 00007f02972c06c0(0000) GS:ffff8881260f6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2a8dc767d0 CR3: 000000007adf0000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:472 [inline] lock_acquire+0x130/0x360 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] mod_memcg_page_state+0xb4/0x750 include/linux/memcontrol.h:928 vfree+0x195/0x330 mm/vmalloc.c:3379 bch2_fs_journal_exit+0x337/0x360 fs/bcachefs/journal.c:1590 __bch2_fs_free fs/bcachefs/super.c:566 [inline] bch2_fs_release+0x254/0x7f0 fs/bcachefs/super.c:618 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 bch2_fs_alloc fs/bcachefs/super.c:981 [inline] bch2_fs_open+0x1a7e/0x2820 fs/bcachefs/super.c:2210 bch2_fs_get_tree+0x45d/0x13b0 fs/bcachefs/fs.c:2491 vfs_get_tree+0x92/0x2b0 fs/super.c:1759 do_new_mount+0x24a/0xa40 fs/namespace.c:3881 do_mount fs/namespace.c:4221 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4409 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: 0033:0x7f029639010a Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f02972bfe68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f02972bfef0 RCX: 00007f029639010a RDX: 0000200000000000 RSI: 0000200000000100 RDI: 00007f02972bfeb0 RBP: 0000200000000000 R08: 00007f02972bfef0 R09: 0000000002000000 R10: 0000000002000000 R11: 0000000000000246 R12: 0000200000000100 R13: 00007f02972bfeb0 R14: 0000000000005a55 R15: 0000200000000080