INFO: task syz-executor.4:25320 blocked for more than 143 seconds. Not tainted 5.15.152-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:22584 pid:25320 ppid: 23515 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 __writeback_inodes_sb_nr+0x2ce/0x370 fs/fs-writeback.c:2684 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2732 ext4_nonda_switch fs/ext4/inode.c:2933 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 ext4_file_write_iter+0x87c/0x1990 __kernel_write+0x5b1/0xa60 fs/read_write.c:539 __dump_emit+0x264/0x3a0 fs/coredump.c:875 dump_user_range+0x91/0x320 fs/coredump.c:949 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285 do_coredump+0x1852/0x31e0 fs/coredump.c:826 get_signal+0xc06/0x14e0 kernel/signal.c:2875 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 irqentry_exit_to_user_mode+0x5/0x40 kernel/entry/common.c:314 exc_page_fault+0x342/0x740 arch/x86/mm/fault.c:1544 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x0 RSP: 002b:0000000020000288 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007fe38d0a2f80 RCX: 00007fe38cf74da9 RDX: 00000000200002c0 RSI: 0000000020000280 RDI: 00000000022a4000 RBP: 00007fe38cfc147a R08: 0000000020000340 R09: 0000000020000340 R10: 0000000020000300 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007fe38d0a2f80 R15: 00007ffd217a8fa8 Showing all locks held in the system: 3 locks held by kworker/u4:0/9: #0: ffff888141f87138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90000ce7d20 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: cfg80211_dfs_channels_update_work+0xbb/0x610 net/wireless/mlme.c:844 1 lock held by khungtaskd/27: #0: ffffffff8c91f720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by dhcpcd/3173: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: __netlink_dump_start+0x12e/0x6f0 net/netlink/af_netlink.c:2348 2 locks held by getty/3255: #0: ffff888024b1c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc9000249b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 2 locks held by kworker/0:4/3527: #0: ffff888011c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90002f27d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 3 locks held by kworker/1:6/3566: #0: ffff888011c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003367d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 5 locks held by kworker/u4:5/3594: 5 locks held by kworker/u4:8/11381: #0: ffff888011dcd138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90005f4fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8d9cfe50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:558 #3: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: ieee80211_unregister_hw+0x4d/0x220 net/mac80211/main.c:1383 #4: ffffffff8c923ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #4: ffffffff8c923ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845 3 locks held by syz-executor.4/25320: #0: ffff888024a8e460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff88802d357198 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] #1: ffff88802d357198 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff888024a8e0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2729 2 locks held by syz-executor.4/26534: 2 locks held by syz-executor.1/26544: 2 locks held by syz-executor.0/26564: 2 locks held by syz-executor.1/26579: 1 lock held by syz-executor.4/26601: 1 lock held by syz-executor.0/26624: 2 locks held by syz-executor.4/26631: 1 lock held by syz-executor.0/26643: 2 locks held by syz-executor.4/26648: 1 lock held by syz-executor.4/26678: 1 lock held by syz-executor.1/26693: 2 locks held by syz-executor.4/26715: 1 lock held by syz-executor.1/26745: 2 locks held by syz-executor.1/29096: 1 lock held by syz-executor.1/29220: 2 locks held by syz-executor.4/29254: 1 lock held by syz-executor.1/29268: 2 locks held by syz-executor.4/29296: 2 locks held by syz-executor.3/29312: 3 locks held by syz-executor.4/29315: 2 locks held by syz-executor.3/29340: 1 lock held by syz-executor.3/29407: #0: ffff888024a90bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677 1 lock held by syz-executor.4/29409: 1 lock held by syz-executor.4/29530: 1 lock held by syz-executor.1/29959: 2 locks held by syz-executor.4/29972: 3 locks held by syz-executor.1/30049: 2 locks held by syz-executor.4/30054: 1 lock held by syz-executor.3/30067: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5626 2 locks held by syz-executor.4/30070: 1 lock held by syz-executor.0/30071: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5626 2 locks held by syz-executor.1/30085: 2 locks held by syz-executor.4/30101: 3 locks held by syz-executor.1/30103: 1 lock held by syz-executor.2/30113: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x460/0x2270 drivers/net/tun.c:3047 2 locks held by syz-executor.4/30126: 2 locks held by syz-executor.1/30134: 2 locks held by syz-executor.4/30142: 2 locks held by syz-executor.1/30151: 2 locks held by syz-executor.4/30155: 3 locks held by syz-executor.1/30167: 2 locks held by syz-executor.4/30168: 2 locks held by syz-executor.4/30195: 3 locks held by syz-executor.1/30199: 2 locks held by syz-executor.1/30212: 3 locks held by syz-executor.4/30213: 2 locks held by syz-executor.4/30220: 2 locks held by syz-executor.1/30226: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1446 Comm: kworker/u4:4 Not tainted 5.15.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:kasan_check_range+0x3/0x290 mm/kasan/generic.c:188 Code: 48 89 c7 e8 cf 72 52 08 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 cc cc cc cc cc cc cc cc cc cc cc cc 55 41 57 <41> 56 53 b0 01 48 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5 0f 82 RSP: 0018:ffffc90006617a68 EFLAGS: 00000256 RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffffffff8164017a RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90006617ae0 RBP: ffffc90006617b50 R08: dffffc0000000000 R09: ffffed100bb1ebd1 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88805d8f5e80 R13: 1ffff92000cc2f5c R14: ffffc90006617ae0 R15: 1ffff1100bb1ebd1 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30521000 CR3: 000000000c68e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:512 [inline] queued_spin_lock include/asm-generic/qspinlock.h:82 [inline] do_raw_spin_lock+0x14a/0x370 kernel/locking/spinlock_debug.c:115 spin_lock_bh include/linux/spinlock.h:368 [inline] batadv_nc_purge_paths+0xe8/0x3b0 net/batman-adv/network-coding.c:446 batadv_nc_worker+0x2cf/0x5b0 net/batman-adv/network-coding.c:724 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298