INFO: task kworker/u8:4:63 blocked for more than 143 seconds. Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:4 state:D stack:19856 pid:63 tgid:63 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-bcachefs-5) Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 io_schedule+0x8d/0x110 kernel/sched/core.c:7681 folio_wait_bit_common+0x839/0xee0 mm/filemap.c:1308 folio_lock include/linux/pagemap.h:1151 [inline] writeback_get_folio mm/page-writeback.c:2515 [inline] writeback_iter+0x8ad/0x12b0 mm/page-writeback.c:2609 write_cache_pages+0xb1/0x230 mm/page-writeback.c:2658 bch2_writepages+0x156/0x390 fs/bcachefs/fs-io-buffered.c:639 do_writepages+0x35f/0x880 mm/page-writeback.c:2702 __writeback_single_inode+0x14f/0x10d0 fs/fs-writeback.c:1680 writeback_sb_inodes+0x820/0x1360 fs/fs-writeback.c:1976 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2047 wb_writeback+0x427/0xb80 fs/fs-writeback.c:2158 wb_check_background_flush fs/fs-writeback.c:2228 [inline] wb_do_writeback fs/fs-writeback.c:2316 [inline] wb_workfn+0xc4b/0x1080 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz.2.38:6308 blocked for more than 143 seconds. Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.38 state:D stack:19792 pid:6308 tgid:6266 ppid:5817 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 io_schedule+0x8d/0x110 kernel/sched/core.c:7681 folio_wait_bit_common+0x839/0xee0 mm/filemap.c:1308 folio_wait_writeback+0xb0/0x100 mm/page-writeback.c:3194 truncate_inode_partial_folio+0x169/0x5e0 mm/truncate.c:192 truncate_inode_pages_range+0x6f3/0x10e0 mm/truncate.c:338 bchfs_fpunch+0x1c1/0x780 fs/bcachefs/fs-io.c:514 bch2_fallocate_dispatch+0x3e4/0x540 fs/bcachefs/fs-io.c:782 vfs_fallocate+0x569/0x6e0 fs/open.c:327 ksys_fallocate fs/open.c:351 [inline] __do_sys_fallocate fs/open.c:356 [inline] __se_sys_fallocate fs/open.c:354 [inline] __x64_sys_fallocate+0xbc/0x110 fs/open.c:354 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffa57b7ff19 RSP: 002b:00007ffa58a28058 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007ffa57d46080 RCX: 00007ffa57b7ff19 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 0000000000000005 RBP: 00007ffa57bf3cc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000002328 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffa57d46080 R15: 00007fffd47106d8 Showing all locks held in the system: 3 locks held by kworker/u8:1/12: 1 lock held by khungtaskd/30: #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 3 locks held by kworker/u8:4/63: #0: ffff8880206ac948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff8880206ac948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90001547d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90001547d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffff88802bc3e0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 2 locks held by dhcpcd/5487: #0: ffff8881447556c8 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xcb/0xe10 net/netlink/af_netlink.c:2263 #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6787 2 locks held by getty/5575: #0: ffff888031fe40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900033132f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz.2.38/6267: #0: ffff888033444b78 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x254/0x320 fs/file.c:1191 #1: ffff88802bc3e420 (sb_writers#15){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #1: ffff88802bc3e420 (sb_writers#15){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 2 locks held by syz.2.38/6308: #0: ffff88802bc3e420 (sb_writers#15){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #0: ffff88802bc3e420 (sb_writers#15){.+.+}-{0:0}, at: vfs_fallocate+0x4fe/0x6e0 fs/open.c:326 #1: ffff888058c18148 (&sb->s_type->i_mutex_key#29){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline] #1: ffff888058c18148 (&sb->s_type->i_mutex_key#29){++++}-{4:4}, at: bch2_fallocate_dispatch+0x1e2/0x540 fs/bcachefs/fs-io.c:771 4 locks held by bch-reclaim/loo/6302: #0: ffff888055fcb0a8 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x167/0x560 fs/bcachefs/journal_reclaim.c:739 #1: ffff888055f84398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888055f84398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888055f84398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7e1/0xd30 fs/bcachefs/btree_iter.c:3228 #2: ffff888055f84740 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x1b19/0x1cc0 fs/bcachefs/btree_write_buffer.c:516 #3: ffff888055fa66d0 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x682/0x14e0 fs/bcachefs/btree_update_interior.c:1197 2 locks held by syz-executor/6530: #0: ffff88807d1be0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807d1be0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807d1be0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8ed51ea8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 3 locks held by kworker/u8:9/7438: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000c90fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000c90fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:281 2 locks held by syz-executor/7439: #0: ffff88804dc600e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88804dc600e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88804dc600e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8ed51ea8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 1 lock held by syz-executor/7917: #0: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz.2.320/9086: #0: ffff88802bc3e0e0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802bc3e0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x196/0x400 fs/super.c:120 2 locks held by syz-executor/9294: #0: ffffffff8f448d20 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8f448d20 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8f448d20 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:555 #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xbb0/0x20e0 net/core/rtnetlink.c:4008 3 locks held by syz-executor/9358: #0: ffffffff8f448d20 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8f448d20 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8f448d20 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:555 #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xbb0/0x20e0 net/core/rtnetlink.c:4008 #2: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #2: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 2 locks held by syz-executor/9436: #0: ffffffff90188238 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff90188238 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff90188238 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:555 #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #1: ffffffff8fc9f008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xbb0/0x20e0 net/core/rtnetlink.c:4008 3 locks held by syz.4.344/9446: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:1 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:clear_page_erms+0xd/0x20 arch/x86/lib/clear_page_64.S:51 Code: 7f 40 75 d9 90 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa b9 00 10 00 00 31 c0 f3 aa cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 RSP: 0018:ffffc90000117390 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: ffff888055cf9000 RSI: 0000000000000007 RDI: ffff888055cfa000 RBP: 0000000000000004 R08: ffffea0001573e37 R09: 0000000000000000 R10: ffffed100ab9f000 R11: fffff940002ae7c7 R12: 0000000000000001 R13: 0000000000000008 R14: ffffea0001573e00 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff14dbff000 CR3: 000000000e736000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: clear_page arch/x86/include/asm/page_64.h:54 [inline] clear_highpage_kasan_tagged include/linux/highmem.h:242 [inline] kernel_init_pages mm/page_alloc.c:1040 [inline] post_alloc_hook+0xf8/0x230 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3474 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269 alloc_slab_page+0x6a/0x110 mm/slub.c:2408 allocate_slab+0x5a/0x2b0 mm/slub.c:2574 new_slab mm/slub.c:2627 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3815 __slab_alloc+0x58/0xa0 mm/slub.c:3905 __slab_alloc_node mm/slub.c:3980 [inline] slab_alloc_node mm/slub.c:4141 [inline] __do_kmalloc_node mm/slub.c:4282 [inline] __kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4302 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1323 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x261/0xb50 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244