last executing test programs:
kernel console output (not intermixed with test programs):
Warning: Permanently added '10.128.1.255' (ED25519) to the list of known hosts.
[ 63.998979][ T133] ------------[ cut here ]------------
[ 64.004591][ T133] WARNING: ./include/linux/backing-dev.h:243 at __folio_start_writeback+0x9d5/0xb70, CPU#0: kworker/u8:5/133
[ 64.016333][ T133] Modules linked in:
[ 64.020344][ T133] CPU: 0 UID: 0 PID: 133 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(full)
[ 64.029745][ T133] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
[ 64.039838][ T133] Workqueue: writeback wb_workfn (flush-8:0)
[ 64.045852][ T133] RIP: 0010:__folio_start_writeback+0x9d5/0xb70
[ 64.052145][ T133] Code: 28 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 de a2 29 00 49 8b 07 25 ff 3f 00 00 e9 1b fa ff ff e8 dc f7 c5 ff 90 <0f> 0b 90 e9 d6 fb ff ff e8 ce f7 c5 ff 48 c7 c7 e0 fe 3f 8e 4c 89
[ 64.071826][ T133] RSP: 0018:ffffc90002e86ea0 EFLAGS: 00010293
[ 64.077906][ T133] RAX: ffffffff81facb54 RBX: ffffea0000c3ec40 RCX: ffff888020720000
[ 64.085917][ T133] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 64.094112][ T133] RBP: ffffc90002e87010 R08: ffffc90002e86f97 R09: 0000000000000000
[ 64.102126][ T133] R10: ffffc90002e86f80 R11: fffff520005d0df3 R12: ffffea0000c3ec48
[ 64.110131][ T133] R13: 0000000000000000 R14: ffff888148c64d80 R15: ffff888148c64b60
[ 64.118108][ T133] FS: 0000000000000000(0000) GS:ffff8881259f8000(0000) knlGS:0000000000000000
[ 64.127062][ T133] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 64.133673][ T133] CR2: 00007faddc789000 CR3: 0000000024276000 CR4: 00000000003526f0
[ 64.141678][ T133] Call Trace:
[ 64.144962][ T133]
[ 64.147894][ T133] ? folio_clear_dirty_for_io+0x226/0x880
[ 64.153694][ T133] ? __pfx___folio_start_writeback+0x10/0x10
[ 64.159830][ T133] ? __pfx_folio_clear_dirty_for_io+0x10/0x10
[ 64.165910][ T133] ? stack_trace_save+0x9c/0xe0
[ 64.170801][ T133] __block_write_full_folio+0x75f/0xe10
[ 64.176358][ T133] ? __pfx_blkdev_get_block+0x10/0x10
[ 64.181761][ T133] blkdev_writepages+0xd1/0x170
[ 64.186614][ T133] ? __pfx_blkdev_writepages+0x10/0x10
[ 64.192151][ T133] ? __pfx_blkdev_writepages+0x10/0x10
[ 64.197722][ T133] do_writepages+0x32b/0x550
[ 64.202495][ T133] __writeback_single_inode+0x145/0xff0
[ 64.208061][ T133] ? wbc_attach_and_unlock_inode+0x3f0/0x5d0
[ 64.214099][ T133] writeback_sb_inodes+0x6c7/0x1010
[ 64.219389][ T133] ? __pfx_writeback_sb_inodes+0x10/0x10
[ 64.225092][ T133] ? __pfx_down_read_trylock+0x10/0x10
[ 64.230594][ T133] ? __pfx___up_read+0x10/0x10
[ 64.235385][ T133] __writeback_inodes_wb+0x111/0x240
[ 64.240719][ T133] wb_writeback+0x44f/0xaf0
[ 64.245276][ T133] ? queue_io+0x381/0x590
[ 64.249647][ T133] ? __pfx_wb_writeback+0x10/0x10
[ 64.254697][ T133] wb_workfn+0xaef/0xef0
[ 64.259153][ T133] ? __pfx_wb_workfn+0x10/0x10
[ 64.263929][ T133] ? __lock_acquire+0xab9/0xd20
[ 64.268830][ T133] ? process_scheduled_works+0x9ef/0x17b0
[ 64.274567][ T133] ? _raw_spin_unlock_irq+0x23/0x50
[ 64.279828][ T133] ? process_scheduled_works+0x9ef/0x17b0
[ 64.285556][ T133] ? process_scheduled_works+0x9ef/0x17b0
[ 64.291373][ T133] process_scheduled_works+0xade/0x17b0
[ 64.297055][ T133] ? __pfx_process_scheduled_works+0x10/0x10
[ 64.303207][ T133] worker_thread+0x8a0/0xda0
[ 64.307802][ T133] ? __pfx__raw_spin_unlock_irqrestore+0x10/0x10
[ 64.314540][ T133] ? __kthread_parkme+0x7b/0x200
[ 64.319528][ T133] kthread+0x70e/0x8a0
[ 64.323615][ T133] ? __pfx_worker_thread+0x10/0x10
[ 64.328793][ T133] ? __pfx_kthread+0x10/0x10
[ 64.333389][ T133] ? _raw_spin_unlock_irq+0x23/0x50
[ 64.338722][ T133] ? lockdep_hardirqs_on+0x9c/0x150
[ 64.343939][ T133] ? __pfx_kthread+0x10/0x10
[ 64.348581][ T133] ret_from_fork+0x47c/0x820
[ 64.353185][ T133] ? __pfx_ret_from_fork+0x10/0x10
[ 64.358359][ T133] ? __switch_to_asm+0x39/0x70
[ 64.363127][ T133] ? __switch_to_asm+0x33/0x70
[ 64.367895][ T133] ? __pfx_kthread+0x10/0x10
[ 64.372562][ T133] ret_from_fork_asm+0x1a/0x30
[ 64.377364][ T133]
[ 64.380443][ T133] Kernel panic - not syncing: kernel: panic_on_warn set ...
[ 64.387722][ T133] CPU: 0 UID: 0 PID: 133 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(full)
[ 64.397089][ T133] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
[ 64.407143][ T133] Workqueue: writeback wb_workfn (flush-8:0)
[ 64.413152][ T133] Call Trace:
[ 64.416434][ T133]
[ 64.419372][ T133] dump_stack_lvl+0x99/0x250
[ 64.423973][ T133] ? __asan_memcpy+0x40/0x70
[ 64.428568][ T133] ? __pfx_dump_stack_lvl+0x10/0x10
[ 64.433791][ T133] ? __pfx__printk+0x10/0x10
[ 64.438404][ T133] vpanic+0x229/0x6d0
[ 64.442390][ T133] ? __pfx_vpanic+0x10/0x10
[ 64.446893][ T133] ? is_bpf_text_address+0x292/0x2b0
[ 64.452182][ T133] ? is_bpf_text_address+0x26/0x2b0
[ 64.457398][ T133] panic+0xb9/0xc0
[ 64.461139][ T133] ? __pfx_panic+0x10/0x10
[ 64.465563][ T133] ? ret_from_fork_asm+0x1a/0x30
[ 64.470499][ T133] __warn+0x334/0x4c0
[ 64.474473][ T133] ? __folio_start_writeback+0x9d5/0xb70
[ 64.480107][ T133] ? __folio_start_writeback+0x9d5/0xb70
[ 64.485735][ T133] report_bug+0x2be/0x4f0
[ 64.490057][ T133] ? __folio_start_writeback+0x9d5/0xb70
[ 64.495682][ T133] ? __folio_start_writeback+0x9d5/0xb70
[ 64.501299][ T133] ? __folio_start_writeback+0x9d7/0xb70
[ 64.506922][ T133] handle_bug+0x84/0x160
[ 64.511152][ T133] exc_invalid_op+0x1a/0x50
[ 64.515640][ T133] asm_exc_invalid_op+0x1a/0x20
[ 64.520479][ T133] RIP: 0010:__folio_start_writeback+0x9d5/0xb70
[ 64.526728][ T133] Code: 28 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 de a2 29 00 49 8b 07 25 ff 3f 00 00 e9 1b fa ff ff e8 dc f7 c5 ff 90 <0f> 0b 90 e9 d6 fb ff ff e8 ce f7 c5 ff 48 c7 c7 e0 fe 3f 8e 4c 89
[ 64.546336][ T133] RSP: 0018:ffffc90002e86ea0 EFLAGS: 00010293
[ 64.552401][ T133] RAX: ffffffff81facb54 RBX: ffffea0000c3ec40 RCX: ffff888020720000
[ 64.560362][ T133] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 64.568324][ T133] RBP: ffffc90002e87010 R08: ffffc90002e86f97 R09: 0000000000000000
[ 64.576291][ T133] R10: ffffc90002e86f80 R11: fffff520005d0df3 R12: ffffea0000c3ec48
[ 64.584271][ T133] R13: 0000000000000000 R14: ffff888148c64d80 R15: ffff888148c64b60
[ 64.592252][ T133] ? __folio_start_writeback+0x9d4/0xb70
[ 64.597895][ T133] ? folio_clear_dirty_for_io+0x226/0x880
[ 64.603641][ T133] ? __pfx___folio_start_writeback+0x10/0x10
[ 64.609624][ T133] ? __pfx_folio_clear_dirty_for_io+0x10/0x10
[ 64.615684][ T133] ? stack_trace_save+0x9c/0xe0
[ 64.620529][ T133] __block_write_full_folio+0x75f/0xe10
[ 64.626066][ T133] ? __pfx_blkdev_get_block+0x10/0x10
[ 64.631442][ T133] blkdev_writepages+0xd1/0x170
[ 64.636285][ T133] ? __pfx_blkdev_writepages+0x10/0x10
[ 64.641749][ T133] ? __pfx_blkdev_writepages+0x10/0x10
[ 64.647193][ T133] do_writepages+0x32b/0x550
[ 64.651786][ T133] __writeback_single_inode+0x145/0xff0
[ 64.657332][ T133] ? wbc_attach_and_unlock_inode+0x3f0/0x5d0
[ 64.663338][ T133] writeback_sb_inodes+0x6c7/0x1010
[ 64.668568][ T133] ? __pfx_writeback_sb_inodes+0x10/0x10
[ 64.674249][ T133] ? __pfx_down_read_trylock+0x10/0x10
[ 64.679725][ T133] ? __pfx___up_read+0x10/0x10
[ 64.684499][ T133] __writeback_inodes_wb+0x111/0x240
[ 64.689787][ T133] wb_writeback+0x44f/0xaf0
[ 64.694291][ T133] ? queue_io+0x381/0x590
[ 64.698615][ T133] ? __pfx_wb_writeback+0x10/0x10
[ 64.703666][ T133] wb_workfn+0xaef/0xef0
[ 64.707927][ T133] ? __pfx_wb_workfn+0x10/0x10
[ 64.712698][ T133] ? __lock_acquire+0xab9/0xd20
[ 64.717560][ T133] ? process_scheduled_works+0x9ef/0x17b0
[ 64.723293][ T133] ? _raw_spin_unlock_irq+0x23/0x50
[ 64.728486][ T133] ? process_scheduled_works+0x9ef/0x17b0
[ 64.734203][ T133] ? process_scheduled_works+0x9ef/0x17b0
[ 64.739922][ T133] process_scheduled_works+0xade/0x17b0
[ 64.745486][ T133] ? __pfx_process_scheduled_works+0x10/0x10
[ 64.751472][ T133] worker_thread+0x8a0/0xda0
[ 64.756054][ T133] ? __pfx__raw_spin_unlock_irqrestore+0x10/0x10
[ 64.762377][ T133] ? __kthread_parkme+0x7b/0x200
[ 64.767310][ T133] kthread+0x70e/0x8a0
[ 64.771381][ T133] ? __pfx_worker_thread+0x10/0x10
[ 64.776502][ T133] ? __pfx_kthread+0x10/0x10
[ 64.781093][ T133] ? _raw_spin_unlock_irq+0x23/0x50
[ 64.786288][ T133] ? lockdep_hardirqs_on+0x9c/0x150
[ 64.791476][ T133] ? __pfx_kthread+0x10/0x10
[ 64.796069][ T133] ret_from_fork+0x47c/0x820
[ 64.800667][ T133] ? __pfx_ret_from_fork+0x10/0x10
[ 64.805779][ T133] ? __switch_to_asm+0x39/0x70
[ 64.810542][ T133] ? __switch_to_asm+0x33/0x70
[ 64.815310][ T133] ? __pfx_kthread+0x10/0x10
[ 64.819911][ T133] ret_from_fork_asm+0x1a/0x30
[ 64.824690][ T133]
[ 64.827939][ T133] Kernel Offset: disabled
[ 64.832343][ T133] Rebooting in 86400 seconds..