INFO: task syz-executor:6973 blocked for more than 143 seconds. Not tainted 6.16.0-rc1-next-20250613-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20808 pid:6973 tgid:6973 ppid:1 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153 kthread_stop+0x194/0x5f0 kernel/kthread.c:791 bch2_copygc_stop+0x4f/0x150 fs/bcachefs/movinggc.c:438 __bch2_fs_read_only+0x47/0x5b0 fs/bcachefs/super.c:281 bch2_fs_read_only+0x42a/0xb00 fs/bcachefs/super.c:367 __bch2_fs_stop+0x100/0x900 fs/bcachefs/super.c:678 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2618 deactivate_locked_super+0xb9/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc778f8fc57 RSP: 002b:00007ffd7c0e3d68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fc779010925 RCX: 00007fc778f8fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd7c0e3e20 RBP: 00007ffd7c0e3e20 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd7c0e4eb0 R13: 00007fc779010925 R14: 0000000000036f52 R15: 00007ffd7c0e4ef0 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967 1 lock held by khungtaskd/31: #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 5 locks held by kworker/u8:3/49: 2 locks held by getty/5594: #0: ffff888034df80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000331b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5839: 1 lock held by syz-executor/5843: 2 locks held by syz-executor/6973: #0: ffff88804db160e0 (&type->s_umount_key#112){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88804db160e0 (&type->s_umount_key#112){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88804db160e0 (&type->s_umount_key#112){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff88804d980278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:677 2 locks held by bch-copygc/loop/7479: #0: ffff88804d984390 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #0: ffff88804d984390 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #0: ffff88804d984390 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3312 #1: ffff88804d9a6710 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x542/0x1dc0 fs/bcachefs/btree_update_interior.c:1202 2 locks held by syz-executor/7665: #0: ffff888079f0c0e0 (&type->s_umount_key#115){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff888079f0c0e0 (&type->s_umount_key#115){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff888079f0c0e0 (&type->s_umount_key#115){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffffffff8e144800 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3792 2 locks held by syz.4.695/9542: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc1-next-20250613-syzkaller #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:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 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: 9542 Comm: syz.4.695 Not tainted 6.16.0-rc1-next-20250613-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x5d/0x70 kernel/kcov.c:235 Code: 18 16 00 00 83 fa 02 75 21 48 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 cc cc cc cc cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 RSP: 0018:ffffc9001c5bf4c8 EFLAGS: 00000246 RAX: ffffffff8b66b42d RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000ca2a000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffff888055950dc0 R08: 0000000000000000 R09: ffffffff81f7f9cd R10: ffffc9001c5bf5a0 R11: fffff520038b7eb7 R12: 0000000000000002 R13: dffffc0000000000 R14: ffff88814d014842 R15: 0000000000000027 FS: 00007fae218d86c0(0000) GS:ffff888125c41000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fae218d7f98 CR3: 0000000029d4e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: xas_descend lib/xarray.c:211 [inline] xas_load+0x44d/0x5b0 lib/xarray.c:246 filemap_get_entry+0x168/0x2f0 mm/filemap.c:1871 shmem_get_folio_gfp+0x237/0x1660 mm/shmem.c:2456 shmem_fault+0x179/0x390 mm/shmem.c:2733 __do_fault+0x135/0x390 mm/memory.c:5187 do_read_fault mm/memory.c:5608 [inline] do_fault mm/memory.c:5742 [inline] do_pte_missing mm/memory.c:4269 [inline] handle_pte_fault mm/memory.c:6087 [inline] __handle_mm_fault+0x37ed/0x5620 mm/memory.c:6230 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399 faultin_page mm/gup.c:1186 [inline] __get_user_pages+0x1aef/0x30b0 mm/gup.c:1488 populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1922 __mm_populate+0x24c/0x380 mm/gup.c:2025 mm_populate include/linux/mm.h:3354 [inline] vm_mmap_pgoff+0x3f0/0x4c0 mm/util.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fae2098e929 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:00007fae218d8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fae20bb5fa0 RCX: 00007fae2098e929 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007fae20a10b39 R08: ffffffffffffffff R09: 000000007be17000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fae20bb5fa0 R15: 00007ffcb7e9fcd8