INFO: task syz.0.16:5041 blocked for more than 143 seconds. Not tainted 5.15.180-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.16 state:D stack:24592 pid: 5041 ppid: 4867 flags:0x00004004 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 schedule_timeout+0xac/0x300 kernel/time/timer.c:1890 do_wait_for_common+0x2d9/0x480 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x48/0x60 kernel/sched/completion.c:138 kthread_stop+0x178/0x580 kernel/kthread.c:666 ext4_stop_mmpd+0x43/0xb0 fs/ext4/mmp.c:263 ext4_fill_super+0x6d67/0xa110 fs/ext4/super.c:5089 mount_bdev+0x2c9/0x3f0 fs/super.c:1400 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x2ba/0xb40 fs/namespace.c:3012 do_mount fs/namespace.c:3355 [inline] __do_sys_mount fs/namespace.c:3563 [inline] __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3540 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fbfaec4590a RSP: 002b:00007fbfadeb4e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fbfadeb4ef0 RCX: 00007fbfaec4590a RDX: 0000400000000040 RSI: 0000400000000000 RDI: 00007fbfadeb4eb0 RBP: 0000400000000040 R08: 00007fbfadeb4ef0 R09: 0000000003010008 R10: 0000000003010008 R11: 0000000000000246 R12: 0000400000000000 R13: 00007fbfadeb4eb0 R14: 0000000000000538 R15: 0000400000000340 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8cb1f4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/u4:3/1185: 2 locks held by getty/3927: #0: ffff88807f008098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cd62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 1 lock held by syz.0.16/5041: #0: ffff88807e31e0e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 1 lock held by syz.1.20/5066: #0: ffff88807db000e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 1 lock held by syz.2.23/5090: #0: ffff88807b8f80e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 1 lock held by syz.3.27/5116: #0: ffff88807a1380e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 1 lock held by syz.4.31/5148: #0: ffff88805c2460e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 1 lock held by syz.5.36/5184: #0: ffff88807c3280e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 1 lock held by syz.6.45/5234: #0: ffff8880225ec0e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 1 lock held by syz.7.52/5280: #0: ffff8880598780e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 1 lock held by syz.8.55/5308: #0: ffff8880788cc0e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 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:212 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:369 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1185 Comm: kworker/u4:3 Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: phy19 ieee80211_iface_work RIP: 0010:__sanitizer_cov_trace_pc+0x58/0x60 kernel/kcov.c:216 Code: 10 16 00 00 83 fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48 8d 7e 01 8b 89 14 16 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89 3a 0f 1f 80 00 00 00 00 4c 8b 04 24 65 48 8b 15 14 2d 82 7e 65 8b RSP: 0018:ffffc90004fa7aa8 EFLAGS: 00000293 RAX: ffffffff81398cf6 RBX: 0000000000000000 RCX: ffff88802251d940 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffea0000000000 R08: ffffffff81398ce8 R09: fffffbfff1c154b6 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff1100e7a3bc7 R14: 0000000076e8b000 R15: 000000000000002e FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c00393a000 CR3: 000000002ba31000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __phys_addr+0xb6/0x170 arch/x86/mm/physaddr.c:28 virt_to_head_page include/linux/mm.h:900 [inline] kfree+0x6e/0x270 mm/slub.c:4554 skb_free_head net/core/skbuff.c:655 [inline] skb_release_data+0x73a/0x8a0 net/core/skbuff.c:677 skb_release_all net/core/skbuff.c:742 [inline] __kfree_skb net/core/skbuff.c:756 [inline] kfree_skb_reason+0xb3/0x170 net/core/skbuff.c:776 kfree_skb include/linux/skbuff.h:1118 [inline] ieee80211_iface_work+0x251/0xcc0 net/mac80211/iface.c:1512 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287