INFO: task syz.7.250:8079 blocked for more than 143 seconds. Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.250 state:D stack:24744 pid:8079 tgid:8020 ppid:7015 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5366 [inline] __schedule+0x1ac3/0x5090 kernel/sched/core.c:6747 __schedule_loop kernel/sched/core.c:6824 [inline] schedule+0x163/0x360 kernel/sched/core.c:6839 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6896 rwsem_down_read_slowpath kernel/locking/rwsem.c:1084 [inline] __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x74c/0xae0 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:877 [inline] lookup_slow+0x45/0x70 fs/namei.c:1823 walk_component+0x2f4/0x420 fs/namei.c:2128 lookup_last fs/namei.c:2626 [inline] path_lookupat+0x169/0x440 fs/namei.c:2650 filename_lookup+0x290/0x670 fs/namei.c:2679 user_path_at+0x3a/0x60 fs/namei.c:3085 do_mount fs/namespace.c:4215 [inline] __do_sys_mount fs/namespace.c:4429 [inline] __se_sys_mount+0x348/0x400 fs/namespace.c:4406 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0d00b8d169 RSP: 002b:00007f0cfe9d5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f0d00da6080 RCX: 00007f0d00b8d169 RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000200000000540 RBP: 00007f0d00c0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000201008 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0d00da6080 R15: 00007ffcdcb23938 INFO: task syz.7.250:8081 blocked for more than 143 seconds. Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.250 state:D stack:28488 pid:8081 tgid:8020 ppid:7015 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5366 [inline] __schedule+0x1ac3/0x5090 kernel/sched/core.c:6747 __schedule_loop kernel/sched/core.c:6824 [inline] schedule+0x163/0x360 kernel/sched/core.c:6839 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6896 rwsem_down_read_slowpath kernel/locking/rwsem.c:1084 [inline] __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x74c/0xae0 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:877 [inline] lookup_slow+0x45/0x70 fs/namei.c:1823 walk_component+0x2f4/0x420 fs/namei.c:2128 lookup_last fs/namei.c:2626 [inline] path_lookupat+0x169/0x440 fs/namei.c:2650 filename_lookup+0x290/0x670 fs/namei.c:2679 user_path_at+0x3a/0x60 fs/namei.c:3085 do_mount fs/namespace.c:4215 [inline] __do_sys_mount fs/namespace.c:4429 [inline] __se_sys_mount+0x348/0x400 fs/namespace.c:4406 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0d00b8d169 RSP: 002b:00007f0cfe9b4038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f0d00da6160 RCX: 00007f0d00b8d169 RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000200000000540 RBP: 00007f0d00c0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000201008 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f0d00da6160 R15: 00007ffcdcb23938 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8eb3a860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8eb3a860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8eb3a860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6761 2 locks held by getty/5582: #0: ffff888034ff80a0 (&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+0x53d/0x16b0 drivers/tty/n_tty.c:2211 5 locks held by syz.7.250/8021: #0: ffff88802a1fc420 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff888044251810 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff888044251810 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: open_last_lookups fs/namei.c:3762 [inline] #1: ffff888044251810 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: path_openat+0x8af/0x35d0 fs/namei.c:4001 #2: ffff888044251bf8 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x359/0xf40 fs/bcachefs/fs.c:550 #3: ffff88804fd84378 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff88804fd84378 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff88804fd84378 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7ed/0xd40 fs/bcachefs/btree_iter.c:3408 #4: ffff88804fda66d0 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68a/0x1680 fs/bcachefs/btree_update_interior.c:1182 1 lock held by syz.7.250/8079: #0: ffff888044251810 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #0: ffff888044251810 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: lookup_slow+0x45/0x70 fs/namei.c:1823 1 lock held by syz.7.250/8081: #0: ffff888044251810 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #0: ffff888044251810 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: lookup_slow+0x45/0x70 fs/namei.c:1823 2 locks held by syz.3.664/12017: 1 lock held by syz.7.665/12020: #0: ffff8880b8639958 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:595 5 locks held by syz.9.666/12027: 2 locks held by dhcpcd-run-hook/12047: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __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: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:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12017 Comm: syz.3.664 Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:unwind_next_frame+0xa6/0x22f0 arch/x86/kernel/unwind_orc.c:479 Code: 85 00 1a 00 00 41 8b 45 00 85 c0 0f 84 f0 18 00 00 89 84 24 84 00 00 00 48 89 6c 24 78 48 89 8c 24 90 00 00 00 48 89 5c 24 20 01 00 00 00 e8 60 9e 22 00 49 8d 6d 50 48 89 e8 48 c1 e8 03 48 RSP: 0018:ffffc9000487ee30 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 1ffff9200090fdec RCX: ffffc9000487ef60 RDX: dffffc0000000000 RSI: ffffc90004878000 RDI: ffffc9000487ef60 RBP: ffffc9000487ef98 R08: ffffc9000487ef50 R09: 0000000000000000 R10: ffffc9000487efb0 R11: fffff5200090fdf8 R12: dffffc0000000000 R13: ffffc9000487ef60 R14: ffffffff816422f7 R15: ffffc9000487ef68 FS: 00007fb8b69636c0(0000) GS:ffff888125359000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4c8acf4270 CR3: 00000000407a4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __unwind_start+0x59a/0x740 arch/x86/kernel/unwind_orc.c:760 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe7/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122 save_stack+0xfc/0x1f0 mm/page_owner.c:156 __set_page_owner+0x90/0x540 mm/page_owner.c:320 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x368a/0x37d0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x2c5/0x7b0 mm/page_alloc.c:4740 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301 folio_alloc_mpol_noprof+0x36/0x70 mm/mempolicy.c:2320 shmem_alloc_folio mm/shmem.c:1863 [inline] shmem_alloc_and_add_folio+0x490/0x1070 mm/shmem.c:1902 shmem_get_folio_gfp+0x655/0x1800 mm/shmem.c:2545 shmem_get_folio mm/shmem.c:2651 [inline] shmem_write_begin+0x17e/0x3a0 mm/shmem.c:3301 generic_perform_write+0x329/0xa10 mm/filemap.c:4102 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3477 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x70f/0xd10 fs/read_write.c:684 ksys_write+0x19d/0x2d0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb8b5b8bc1f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007fb8b6962df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fb8b5b8bc1f RDX: 0000000001000000 RSI: 00007fb8ab400000 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005598 R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000005 R13: 00007fb8b6962ef0 R14: 00007fb8b6962eb0 R15: 00007fb8ab400000