last executing test programs:
kernel console output (not intermixed with test programs):
Warning: Permanently added '10.128.0.156' (ED25519) to the list of known hosts.
[ 66.992675][ T2949] ------------[ cut here ]------------
[ 66.998299][ T2949] WARNING: ./include/linux/backing-dev.h:243 at __folio_start_writeback+0x9d5/0xb70, CPU#1: kworker/u8:6/2949
[ 67.010693][ T2949] Modules linked in:
[ 67.014725][ T2949] CPU: 1 UID: 0 PID: 2949 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT(full)
[ 67.024326][ T2949] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
[ 67.034550][ T2949] Workqueue: writeback wb_workfn (flush-8:0)
[ 67.040583][ T2949] RIP: 0010:__folio_start_writeback+0x9d5/0xb70
[ 67.046878][ T2949] Code: 28 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 ce a2 29 00 49 8b 07 25 ff 3f 00 00 e9 1b fa ff ff e8 7c 04 c6 ff 90 <0f> 0b 90 e9 d6 fb ff ff e8 6e 04 c6 ff 48 c7 c7 a0 f8 5f 8e 4c 89
[ 67.066827][ T2949] RSP: 0018:ffffc9000bb06ea0 EFLAGS: 00010293
[ 67.073353][ T2949] RAX: ffffffff81fad344 RBX: ffffea00050de8c0 RCX: ffff88802ee29e00
[ 67.081356][ T2949] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 67.089392][ T2949] RBP: ffffc9000bb07010 R08: ffffc9000bb06f97 R09: 0000000000000000
[ 67.097422][ T2949] R10: ffffc9000bb06f80 R11: fffff52001760df3 R12: ffffea00050de8c8
[ 67.105475][ T2949] R13: 0000000000000000 R14: ffff888023060880 R15: ffff888023060660
[ 67.113585][ T2949] FS: 0000000000000000(0000) GS:ffff8881258c3000(0000) knlGS:0000000000000000
[ 67.122572][ T2949] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 67.129161][ T2949] CR2: 00007f7354907000 CR3: 000000000e338000 CR4: 00000000003526f0
[ 67.137264][ T2949] Call Trace:
[ 67.140558][ T2949]
[ 67.143575][ T2949] ? folio_clear_dirty_for_io+0x226/0x880
[ 67.149316][ T2949] ? __pfx___folio_start_writeback+0x10/0x10
[ 67.155406][ T2949] ? __pfx_folio_clear_dirty_for_io+0x10/0x10
[ 67.161683][ T2949] ? stack_trace_save+0x9c/0xe0
[ 67.166721][ T2949] __block_write_full_folio+0x75f/0xe10
[ 67.172333][ T2949] ? __pfx_blkdev_get_block+0x10/0x10
[ 67.177922][ T2949] blkdev_writepages+0xd1/0x170
[ 67.182859][ T2949] ? __pfx_blkdev_writepages+0x10/0x10
[ 67.188358][ T2949] ? __pfx_blkdev_writepages+0x10/0x10
[ 67.193875][ T2949] do_writepages+0x32e/0x550
[ 67.198507][ T2949] __writeback_single_inode+0x145/0xff0
[ 67.204137][ T2949] ? wbc_attach_and_unlock_inode+0x3f0/0x5d0
[ 67.210168][ T2949] writeback_sb_inodes+0x6c7/0x1010
[ 67.215459][ T2949] ? __pfx_writeback_sb_inodes+0x10/0x10
[ 67.221146][ T2949] ? __pfx_down_read_trylock+0x10/0x10
[ 67.226700][ T2949] ? __pfx___up_read+0x10/0x10
[ 67.231493][ T2949] __writeback_inodes_wb+0x111/0x240
[ 67.236883][ T2949] wb_writeback+0x44f/0xaf0
[ 67.241411][ T2949] ? queue_io+0x351/0x590
[ 67.245831][ T2949] ? __pfx_wb_writeback+0x10/0x10
[ 67.250891][ T2949] wb_workfn+0xaef/0xef0
[ 67.255306][ T2949] ? __pfx_wb_workfn+0x10/0x10
[ 67.260274][ T2949] ? __lock_acquire+0xab9/0xd20
[ 67.265196][ T2949] ? process_scheduled_works+0x9ef/0x17b0
[ 67.271116][ T2949] ? _raw_spin_unlock_irq+0x23/0x50
[ 67.276414][ T2949] ? process_scheduled_works+0x9ef/0x17b0
[ 67.282190][ T2949] ? process_scheduled_works+0x9ef/0x17b0
[ 67.287936][ T2949] process_scheduled_works+0xade/0x17b0
[ 67.293585][ T2949] ? __pfx_process_scheduled_works+0x10/0x10
[ 67.299594][ T2949] worker_thread+0x8a0/0xda0
[ 67.304273][ T2949] kthread+0x711/0x8a0
[ 67.308372][ T2949] ? __pfx_worker_thread+0x10/0x10
[ 67.313656][ T2949] ? __pfx_kthread+0x10/0x10
[ 67.318257][ T2949] ? _raw_spin_unlock_irq+0x23/0x50
[ 67.323507][ T2949] ? lockdep_hardirqs_on+0x9c/0x150
[ 67.328718][ T2949] ? __pfx_kthread+0x10/0x10
[ 67.333403][ T2949] ret_from_fork+0x47c/0x820
[ 67.338010][ T2949] ? __pfx_ret_from_fork+0x10/0x10
[ 67.343724][ T2949] ? __switch_to_asm+0x39/0x70
[ 67.348588][ T2949] ? __switch_to_asm+0x33/0x70
[ 67.353619][ T2949] ? __pfx_kthread+0x10/0x10
[ 67.358412][ T2949] ret_from_fork_asm+0x1a/0x30
[ 67.363260][ T2949]
[ 67.366285][ T2949] Kernel panic - not syncing: kernel: panic_on_warn set ...
[ 67.373607][ T2949] CPU: 1 UID: 0 PID: 2949 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT(full)
[ 67.383420][ T2949] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
[ 67.393835][ T2949] Workqueue: writeback wb_workfn (flush-8:0)
[ 67.400127][ T2949] Call Trace:
[ 67.403431][ T2949]
[ 67.406448][ T2949] dump_stack_lvl+0x99/0x250
[ 67.411061][ T2949] ? __asan_memcpy+0x40/0x70
[ 67.415772][ T2949] ? __pfx_dump_stack_lvl+0x10/0x10
[ 67.421119][ T2949] ? __pfx__printk+0x10/0x10
[ 67.425748][ T2949] vpanic+0x281/0x750
[ 67.429835][ T2949] ? __pfx_vpanic+0x10/0x10
[ 67.434354][ T2949] ? is_bpf_text_address+0x292/0x2b0
[ 67.439649][ T2949] ? is_bpf_text_address+0x26/0x2b0
[ 67.444878][ T2949] panic+0xb9/0xc0
[ 67.448610][ T2949] ? __pfx_panic+0x10/0x10
[ 67.453051][ T2949] ? ret_from_fork_asm+0x1a/0x30
[ 67.457998][ T2949] __warn+0x334/0x4c0
[ 67.462146][ T2949] ? __folio_start_writeback+0x9d5/0xb70
[ 67.467858][ T2949] ? __folio_start_writeback+0x9d5/0xb70
[ 67.473479][ T2949] report_bug+0x2be/0x4f0
[ 67.477932][ T2949] ? __folio_start_writeback+0x9d5/0xb70
[ 67.483577][ T2949] ? __folio_start_writeback+0x9d5/0xb70
[ 67.489562][ T2949] ? __folio_start_writeback+0x9d7/0xb70
[ 67.495187][ T2949] handle_bug+0x84/0x160
[ 67.499424][ T2949] exc_invalid_op+0x1a/0x50
[ 67.503974][ T2949] asm_exc_invalid_op+0x1a/0x20
[ 67.508831][ T2949] RIP: 0010:__folio_start_writeback+0x9d5/0xb70
[ 67.515064][ T2949] Code: 28 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 ce a2 29 00 49 8b 07 25 ff 3f 00 00 e9 1b fa ff ff e8 7c 04 c6 ff 90 <0f> 0b 90 e9 d6 fb ff ff e8 6e 04 c6 ff 48 c7 c7 a0 f8 5f 8e 4c 89
[ 67.534675][ T2949] RSP: 0018:ffffc9000bb06ea0 EFLAGS: 00010293
[ 67.540835][ T2949] RAX: ffffffff81fad344 RBX: ffffea00050de8c0 RCX: ffff88802ee29e00
[ 67.548912][ T2949] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 67.556884][ T2949] RBP: ffffc9000bb07010 R08: ffffc9000bb06f97 R09: 0000000000000000
[ 67.564854][ T2949] R10: ffffc9000bb06f80 R11: fffff52001760df3 R12: ffffea00050de8c8
[ 67.572823][ T2949] R13: 0000000000000000 R14: ffff888023060880 R15: ffff888023060660
[ 67.580901][ T2949] ? __folio_start_writeback+0x9d4/0xb70
[ 67.586541][ T2949] ? folio_clear_dirty_for_io+0x226/0x880
[ 67.592354][ T2949] ? __pfx___folio_start_writeback+0x10/0x10
[ 67.598371][ T2949] ? __pfx_folio_clear_dirty_for_io+0x10/0x10
[ 67.604464][ T2949] ? stack_trace_save+0x9c/0xe0
[ 67.609337][ T2949] __block_write_full_folio+0x75f/0xe10
[ 67.614889][ T2949] ? __pfx_blkdev_get_block+0x10/0x10
[ 67.620351][ T2949] blkdev_writepages+0xd1/0x170
[ 67.625198][ T2949] ? __pfx_blkdev_writepages+0x10/0x10
[ 67.630859][ T2949] ? __pfx_blkdev_writepages+0x10/0x10
[ 67.636337][ T2949] do_writepages+0x32e/0x550
[ 67.640951][ T2949] __writeback_single_inode+0x145/0xff0
[ 67.646499][ T2949] ? wbc_attach_and_unlock_inode+0x3f0/0x5d0
[ 67.652484][ T2949] writeback_sb_inodes+0x6c7/0x1010
[ 67.657693][ T2949] ? __pfx_writeback_sb_inodes+0x10/0x10
[ 67.663442][ T2949] ? __pfx_down_read_trylock+0x10/0x10
[ 67.668931][ T2949] ? __pfx___up_read+0x10/0x10
[ 67.673718][ T2949] __writeback_inodes_wb+0x111/0x240
[ 67.679047][ T2949] wb_writeback+0x44f/0xaf0
[ 67.683554][ T2949] ? queue_io+0x351/0x590
[ 67.687876][ T2949] ? __pfx_wb_writeback+0x10/0x10
[ 67.692905][ T2949] wb_workfn+0xaef/0xef0
[ 67.697161][ T2949] ? __pfx_wb_workfn+0x10/0x10
[ 67.702012][ T2949] ? __lock_acquire+0xab9/0xd20
[ 67.706980][ T2949] ? process_scheduled_works+0x9ef/0x17b0
[ 67.712809][ T2949] ? _raw_spin_unlock_irq+0x23/0x50
[ 67.718031][ T2949] ? process_scheduled_works+0x9ef/0x17b0
[ 67.723763][ T2949] ? process_scheduled_works+0x9ef/0x17b0
[ 67.729518][ T2949] process_scheduled_works+0xade/0x17b0
[ 67.735112][ T2949] ? __pfx_process_scheduled_works+0x10/0x10
[ 67.741132][ T2949] worker_thread+0x8a0/0xda0
[ 67.745761][ T2949] kthread+0x711/0x8a0
[ 67.749871][ T2949] ? __pfx_worker_thread+0x10/0x10
[ 67.755065][ T2949] ? __pfx_kthread+0x10/0x10
[ 67.759659][ T2949] ? _raw_spin_unlock_irq+0x23/0x50
[ 67.764889][ T2949] ? lockdep_hardirqs_on+0x9c/0x150
[ 67.770262][ T2949] ? __pfx_kthread+0x10/0x10
[ 67.774939][ T2949] ret_from_fork+0x47c/0x820
[ 67.779524][ T2949] ? __pfx_ret_from_fork+0x10/0x10
[ 67.784639][ T2949] ? __switch_to_asm+0x39/0x70
[ 67.789406][ T2949] ? __switch_to_asm+0x33/0x70
[ 67.794266][ T2949] ? __pfx_kthread+0x10/0x10
[ 67.799047][ T2949] ret_from_fork_asm+0x1a/0x30
[ 67.803820][ T2949]
[ 67.807131][ T2949] Kernel Offset: disabled
[ 67.811892][ T2949] Rebooting in 86400 seconds..