INFO: task syz-executor.3:28714 blocked for more than 143 seconds. Not tainted 6.6.0-rc7-syzkaller-00039-g4f82870119a4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:24464 pid:28714 ppid:5055 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0xee1/0x5a10 kernel/sched/core.c:6695 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 wb_wait_for_completion+0x1ae/0x270 fs/fs-writeback.c:192 __writeback_inodes_sb_nr+0x1d8/0x270 fs/fs-writeback.c:2655 try_to_writeback_inodes_sb+0x97/0xc0 fs/fs-writeback.c:2703 ext4_nonda_switch+0x1a9/0x1f0 fs/ext4/inode.c:2836 ext4_da_write_begin+0x16e/0x8c0 fs/ext4/inode.c:2863 generic_perform_write+0x278/0x600 mm/filemap.c:3969 ext4_buffered_write_iter+0x11f/0x3c0 fs/ext4/file.c:299 ext4_file_write_iter+0x7f7/0x1860 fs/ext4/file.c:717 __kernel_write_iter+0x261/0x7e0 fs/read_write.c:517 dump_emit_page fs/coredump.c:888 [inline] dump_user_range+0x299/0x790 fs/coredump.c:915 elf_core_dump+0x2700/0x3900 fs/binfmt_elf.c:2142 do_coredump+0x2c96/0x3fc0 fs/coredump.c:764 get_signal+0x2434/0x2790 kernel/signal.c:2878 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:309 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564 RIP: 0033:0x7f20f8e7caf1 RSP: 002b:00000000200002b0 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f20f8f9bf80 RCX: 00007f20f8e7cae9 RDX: 00000000200002c0 RSI: 00000000200002b0 RDI: 0000000004000000 RBP: 00007f20f8ec847a R08: 0000000020000340 R09: 0000000020000340 R10: 0000000020000300 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007f20f8f9bf80 R15: 00007ffec57997d8 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cbab2e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:303 [inline] #0: ffffffff8cbab2e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:749 [inline] #0: ffffffff8cbab2e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613 3 locks held by kworker/u4:8/2775: #0: ffff888015264138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc9000a16fd80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 2 locks held by kworker/1:3/4504: #0: ffff888012c72938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc9000327fd80 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 2 locks held by getty/4789: #0: ffff88802a17a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc5/0x1480 drivers/tty/n_tty.c:2206 3 locks held by syz-executor.3/28714: #0: ffff88802a722410 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x2434/0x2790 kernel/signal.c:2878 #1: ffff888056ac5400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #1: ffff888056ac5400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x3c0 fs/ext4/file.c:294 #2: ffff88802a7220e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2700 1 lock held by syz-executor.3/29103: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29245: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29250: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29255: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29259: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.4/29309: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.4/29322: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.4/29366: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29368: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.4/29917: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29920: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29931: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29934: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.3/29939: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 3 locks held by syz-executor.5/29940: 1 lock held by syz-executor.3/29946: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 2 locks held by syz-executor.3/29952: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 #1: ffff88802a726988 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x10d6/0x15e0 fs/jbd2/transaction.c:463 1 lock held by syz-executor.3/29959: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 2 locks held by syz-executor.5/30064: 3 locks held by syz-executor.3/30077: 1 lock held by syz-executor.1/30078: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.2/30079: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.0/30080: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.4/30082: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 2 locks held by syz-executor.5/30085: 2 locks held by syz-executor.3/30096: 2 locks held by syz-executor.5/30099: 4 locks held by syz-executor.3/30107: 2 locks held by syz-executor.5/30114: 3 locks held by syz-executor.3/30122: 2 locks held by syz-executor.0/30195: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 #1: ffff88802a726988 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x10d6/0x15e0 fs/jbd2/transaction.c:463 2 locks held by syz-executor.4/30196: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 #1: ffff88802a726988 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x10d6/0x15e0 fs/jbd2/transaction.c:463 1 lock held by syz-executor.2/30198: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 2 locks held by syz-executor.5/30213: 3 locks held by syz-executor.3/30217: 2 locks held by syz-executor.5/30235: 2 locks held by syz-executor.3/30237: 3 locks held by syz-executor.5/30248: 2 locks held by syz-executor.3/30254: 2 locks held by syz-executor.5/30267: 1 lock held by syz-executor.0/30358: #0: ffffffff8e5cd110 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2d5/0x670 net/core/net_namespace.c:487 2 locks held by syz-executor.1/30357: #0: ffffffff8e5cd110 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2d5/0x670 net/core/net_namespace.c:487 #1: ffffffff8e5e2468 (rtnl_mutex){+.+.}-{3:3}, at: sit_exit_batch_net+0x8c/0x580 net/ipv6/sit.c:1883 1 lock held by syz-executor.1/30359: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.2/30377: #0: ffffffff8e5cd110 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2d5/0x670 net/core/net_namespace.c:487 1 lock held by syz-executor.2/30368: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 2 locks held by syz-executor.4/30369: #0: ffffffff8e5cd110 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2d5/0x670 net/core/net_namespace.c:487 #1: ffffffff8cbb6bb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #1: ffffffff8cbb6bb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x404/0x7e0 kernel/rcu/tree_exp.h:992 1 lock held by syz-executor.4/30371: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 1 lock held by syz-executor.0/30361: #0: ffff88802a724bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 2 locks held by syz-executor.5/30410: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.0-rc7-syzkaller-00039-g4f82870119a4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf87/0x1210 kernel/hung_task.c:379 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 29424 Comm: kworker/u4:5 Not tainted 6.6.0-rc7-syzkaller-00039-g4f82870119a4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:write_comp_data+0x7/0x90 kernel/kcov.c:230 Code: 81 e2 00 01 ff 00 75 10 65 48 8b 04 25 c0 bc 03 00 48 8b 80 f8 15 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 65 8b 05 71 e8 7b 7e <49> 89 f1 89 c6 49 89 d2 81 e6 00 01 00 00 49 89 f8 65 48 8b 14 25 RSP: 0018:ffffc900162f6f78 EFLAGS: 00000202 RAX: 0000000080000202 RBX: 0000000000000002 RCX: ffffffff813a64da RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffffffff8a89d020 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffff8880b9829418 R12: 0000000000000001 R13: 0000000000000001 R14: 0000000000000003 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000001ffffec0 CR3: 000000000c976000 CR4: 0000000000350ef0 Call Trace: __sanitizer_cov_trace_switch+0x54/0x90 kernel/kcov.c:341 unwind_next_frame+0xeaa/0x2390 arch/x86/kernel/unwind_orc.c:641 arch_stack_walk+0xfa/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3822 ieee80211_inform_bss+0xb2f/0x1150 net/mac80211/scan.c:160 rdev_inform_bss+0xea/0x420 net/wireless/rdev-ops.h:418 cfg80211_inform_single_bss_frame_data+0x82d/0xf30 net/wireless/scan.c:2889 cfg80211_inform_bss_frame_data+0xbf/0x290 net/wireless/scan.c:2916 ieee80211_bss_info_update+0x374/0x990 net/mac80211/scan.c:211 ieee80211_rx_bss_info net/mac80211/ibss.c:1124 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1613 [inline] ieee80211_ibss_rx_queued_mgmt+0x195a/0x2ed0 net/mac80211/ibss.c:1642 ieee80211_iface_process_skb net/mac80211/iface.c:1604 [inline] ieee80211_iface_work+0xa1f/0xd40 net/mac80211/iface.c:1658 cfg80211_wiphy_work+0x24e/0x330 net/wireless/core.c:435 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304