INFO: task syz-executor336:5838 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-executor336 state:D stack:19384 pid:5838 tgid:5838 ppid:5837 task_flags:0x400140 flags:0x00004006 Call Trace: 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 __closure_sync+0x1c0/0x2a0 lib/closure.c:146 bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:254 [inline] bch2_btree_update_start+0x12bd/0x16c0 fs/bcachefs/btree_update_interior.c:1251 bch2_btree_split_leaf+0x12d/0x8a0 fs/bcachefs/btree_update_interior.c:1864 bch2_trans_commit_error+0x1b3/0x1480 fs/bcachefs/btree_trans_commit.c:904 __bch2_trans_commit+0x8886/0x9da0 fs/bcachefs/btree_trans_commit.c:1069 bch2_trans_commit fs/bcachefs/btree_update.h:195 [inline] __bch2_create+0xa79/0xf40 fs/bcachefs/fs.c:576 bch2_mknod fs/bcachefs/fs.c:728 [inline] bch2_create+0xec/0x1c0 fs/bcachefs/fs.c:742 lookup_open fs/namei.c:3701 [inline] open_last_lookups fs/namei.c:3800 [inline] path_openat+0x194b/0x35d0 fs/namei.c:4036 do_filp_open+0x284/0x4e0 fs/namei.c:4066 do_sys_openat2+0x12b/0x1d0 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+0x249/0x2a0 fs/open.c:1455 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: 0033:0x7f091a492ad9 RSP: 002b:00007ffe19f4e818 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f091a492ad9 RDX: 000000000000275a RSI: 00002000000001c0 RDI: 00000000ffffff9c RBP: 00007f091a5155f0 R08: 000000000000f624 R09: 000055559006d4c0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe19f4e840 R13: 00007ffe19f4ea68 R14: 431bde82d7b634db R15: 00007f091a4db03b 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 2 locks held by getty/5591: #0: ffff888035bb90a0 (&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+0x5bb/0x1700 drivers/tty/n_tty.c:2222 5 locks held by syz-executor336/5838: #0: ffff88807ed90420 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff888072150148 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff888072150148 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline] #1: ffff888072150148 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: path_openat+0x8af/0x35d0 fs/namei.c:4036 #2: ffff888072150530 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x359/0xf40 fs/bcachefs/fs.c:550 #3: ffff888073d84228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff888073d84228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff888073d84228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7ed/0xd40 fs/bcachefs/btree_iter.c:3382 #4: ffff888073da6590 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x68a/0x16c0 fs/bcachefs/btree_update_interior.c:1179 1 lock held by bch-copygc/loop/5848: ============================================= 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: __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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5848 Comm: bch-copygc/loop 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:rcu_is_watching+0x67/0xb0 kernel/rcu/tree.c:737 Code: 89 f7 e8 6c 3d 82 00 48 c7 c3 58 3b 66 93 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 22 8b 03 65 ff 0d a9 e2 bc 11 <74> 10 83 e0 04 c1 e8 02 5b 41 5e 41 5f c3 cc cc cc cc e8 e2 1b 82 RSP: 0018:ffffc90004046ec0 EFLAGS: 00000286 RAX: 000000000002b79c RBX: ffff8880b8632b58 RCX: ffff88807aad1e00 RDX: dffffc0000000000 RSI: ffffffff8ca0e160 RDI: ffffffff8ca0e120 RBP: ffffffff816d9bc8 R08: ffffc90004047070 R09: 0000000000000000 R10: ffffc900040470d0 R11: fffff52000808e1c R12: ffffc90004047090 R13: dffffc0000000000 R14: ffffffff8e786c10 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f274edb5580 CR3: 000000000eb38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x4e/0x3e0 kernel/locking/lockdep.c:5877 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x1a9f/0x23b0 arch/x86/kernel/unwind_orc.c:680 __unwind_start+0x59a/0x740 arch/x86/kernel/unwind_orc.c:758 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 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4341 [inline] __kvmalloc_node_noprof+0x329/0x5a0 mm/slub.c:5026 __bch2_darray_resize_noprof+0xd2/0x290 fs/bcachefs/darray.c:24 bch2_copygc_get_buckets fs/bcachefs/movinggc.c:169 [inline] bch2_copygc+0x23d2/0x4db0 fs/bcachefs/movinggc.c:221 bch2_copygc_thread+0x705/0xc00 fs/bcachefs/movinggc.c:398 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 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.440 msecs