INFO: task syz.0.17:6038 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:23440 pid:6038  tgid:6038  ppid:5991   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 io_schedule+0x80/0xd0 kernel/sched/core.c:7903
 folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317
 folio_lock include/linux/pagemap.h:1139 [inline]
 writeback_get_folio mm/page-writeback.c:2468 [inline]
 writeback_iter+0x8d8/0x12a0 mm/page-writeback.c:2562
 iomap_writepages+0x14d/0x2d0 fs/iomap/buffered-io.c:1761
 gfs2_writepages+0x177/0x250 fs/gfs2/aops.c:175
 do_writepages+0x32e/0x550 mm/page-writeback.c:2634
 filemap_fdatawrite_wbc mm/filemap.c:386 [inline]
 __filemap_fdatawrite_range mm/filemap.c:419 [inline]
 __filemap_fdatawrite mm/filemap.c:425 [inline]
 filemap_fdatawrite+0x199/0x240 mm/filemap.c:430
 gfs2_ordered_write fs/gfs2/log.c:733 [inline]
 gfs2_log_flush+0x966/0x24c0 fs/gfs2/log.c:1102
 gfs2_trans_end+0x37c/0x570 fs/gfs2/trans.c:158
 gfs2_page_mkwrite+0x14a8/0x1910 fs/gfs2/file.c:535
 do_page_mkwrite+0x14d/0x310 mm/memory.c:3489
 do_shared_fault mm/memory.c:5779 [inline]
 do_fault mm/memory.c:5841 [inline]
 do_pte_missing mm/memory.c:4362 [inline]
 handle_pte_fault mm/memory.c:6182 [inline]
 __handle_mm_fault+0x1916/0x5400 mm/memory.c:6323
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6492
 do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7ff8d7655171
RSP: 002b:00007ffcc4a8a3d0 EFLAGS: 00010246
RAX: 00002000000003c0 RBX: 0000000000000004 RCX: 0000000000000000
RDX: 0000000000000004 RSI: 0000000000000000 RDI: 000055557d4103c8
RBP: 00007ffcc4a8a4d8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00007ff8d79b5fac
R13: 00007ff8d79b5fa0 R14: fffffffffffffffe R15: 0000000000000006
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 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:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf60/0xfa0 kernel/hung_task.c:495
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6753 Comm: syz.1.243 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 1e 6e 6d fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 cf 17 d1 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900049e6978 EFLAGS: 00000006
RAX: 1ffffffff3401505 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc900049e6b50 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff85532060 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff9a00af20 R15: 0000000000000000
FS:  0000555592340500(0000) GS:ffff888125aff000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff15c3ff000 CR3: 0000000076050000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 serial_port_in include/linux/serial_core.h:806 [inline]
 serial8250_console_write+0x581/0x1ba0 drivers/tty/serial/8250/8250_port.c:3306
 console_emit_next_record kernel/printk/printk.c:3138 [inline]
 console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
 _printk+0xcf/0x120 kernel/printk/printk.c:2475
 set_capacity_and_notify+0x208/0x2d0 block/genhd.c:93
 loop_set_size+0x44/0xb0 drivers/block/loop.c:214
 loop_configure+0x9f4/0xe50 drivers/block/loop.c:1071
 lo_ioctl+0x810/0x1b30 drivers/block/loop.c:-1
 blkdev_ioctl+0x5a8/0x6d0 block/ioctl.c:705
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff16438e7eb
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007ffc00526480 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007ff16438e7eb
RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000001f78a
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007ffc005265b0 R14: 00007ffc00526570 R15: 00007ff15b400000
 </TASK>