last executing test programs:
kernel console output (not intermixed with test programs):
[ 63.762386][ T996] ------------[ cut here ]------------
[ 63.767950][ T996] WARNING: ./include/linux/backing-dev.h:243 at __folio_start_writeback+0x8e7/0xa50, CPU#1: kworker/u8:5/996
[ 63.779871][ T996] Modules linked in:
[ 63.784145][ T996] CPU: 1 UID: 0 PID: 996 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(full)
[ 63.793581][ T996] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
[ 63.803670][ T996] Workqueue: writeback wb_workfn (flush-8:0)
[ 63.809656][ T996] RIP: 0010:__folio_start_writeback+0x8e7/0xa50
[ 63.815937][ T996] Code: 8b 05 2d 17 c8 10 48 3b 84 24 20 01 00 00 75 3b 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 10 5d 88 09 cc e8 1a fa c5 ff 90 <0f> 0b 90 e9 e5 fb ff ff e8 0c fa c5 ff 48 c7 c7 20 ff 3f 8e 4c 89
[ 63.835626][ T996] RSP: 0018:ffffc90003806ea0 EFLAGS: 00010293
[ 63.841778][ T996] RAX: ffffffff81fab916 RBX: ffffea0000931400 RCX: ffff888025e01e00
[ 63.849784][ T996] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 63.857801][ T996] RBP: ffffc90003807010 R08: ffffc90003806f97 R09: 0000000000000000
[ 63.865818][ T996] R10: ffffc90003806f80 R11: fffff52000700df3 R12: ffffea0000931408
[ 63.874024][ T996] R13: 0000000000000000 R14: ffff888148c5cd80 R15: ffff888148c5cb60
[ 63.882038][ T996] FS: 0000000000000000(0000) GS:ffff888125af3000(0000) knlGS:0000000000000000
[ 63.890969][ T996] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 63.897649][ T996] CR2: 000056327a3bb660 CR3: 000000007cb0a000 CR4: 00000000003526f0
[ 63.905679][ T996] Call Trace:
[ 63.908963][ T996]
[ 63.911974][ T996] ? __pfx___folio_start_writeback+0x10/0x10
[ 63.917979][ T996] ? __pfx_folio_clear_dirty_for_io+0x10/0x10
[ 63.924111][ T996] ? irqentry_exit+0x74/0x90
[ 63.928720][ T996] __block_write_full_folio+0x75f/0xe10
[ 63.934321][ T996] ? __pfx_blkdev_get_block+0x10/0x10
[ 63.939726][ T996] blkdev_writepages+0xd1/0x170
[ 63.944632][ T996] ? __pfx_blkdev_writepages+0x10/0x10
[ 63.950114][ T996] ? __pfx_blkdev_writepages+0x10/0x10
[ 63.955635][ T996] do_writepages+0x32e/0x550
[ 63.960239][ T996] __writeback_single_inode+0x145/0xff0
[ 63.965816][ T996] ? wbc_attach_and_unlock_inode+0x3f0/0x5d0
[ 63.971858][ T996] writeback_sb_inodes+0x6c7/0x1010
[ 63.977092][ T996] ? __pfx_writeback_sb_inodes+0x10/0x10
[ 63.982798][ T996] ? __pfx_down_read_trylock+0x10/0x10
[ 63.988305][ T996] ? __pfx___up_read+0x10/0x10
[ 63.993142][ T996] __writeback_inodes_wb+0x111/0x240
[ 63.998439][ T996] wb_writeback+0x44f/0xaf0
[ 64.003214][ T996] ? queue_io+0x321/0x590
[ 64.007596][ T996] ? __pfx_wb_writeback+0x10/0x10
[ 64.012774][ T996] wb_workfn+0xaef/0xef0
[ 64.017027][ T996] ? __pfx_wb_workfn+0x10/0x10
[ 64.021826][ T996] ? __lock_acquire+0xab9/0xd20
[ 64.026697][ T996] ? process_scheduled_works+0x9ef/0x17b0
[ 64.032483][ T996] ? _raw_spin_unlock_irq+0x23/0x50
[ 64.037691][ T996] ? process_scheduled_works+0x9ef/0x17b0
[ 64.043458][ T996] ? process_scheduled_works+0x9ef/0x17b0
[ 64.049197][ T996] process_scheduled_works+0xade/0x17b0
[ 64.054811][ T996] ? __pfx_process_scheduled_works+0x10/0x10
[ 64.060807][ T996] worker_thread+0x8a0/0xda0
[ 64.065604][ T996] ? __pfx__raw_spin_unlock_irqrestore+0x10/0x10
[ 64.071990][ T996] ? __kthread_parkme+0x7b/0x200
[ 64.076924][ T996] kthread+0x70e/0x8a0
[ 64.080981][ T996] ? __pfx_worker_thread+0x10/0x10
[ 64.086126][ T996] ? __pfx_kthread+0x10/0x10
[ 64.090720][ T996] ? _raw_spin_unlock_irq+0x23/0x50
[ 64.095993][ T996] ? lockdep_hardirqs_on+0x9c/0x150
[ 64.101197][ T996] ? __pfx_kthread+0x10/0x10
[ 64.105845][ T996] ret_from_fork+0x47c/0x820
[ 64.110482][ T996] ? __pfx_ret_from_fork+0x10/0x10
[ 64.115662][ T996] ? __switch_to_asm+0x39/0x70
[ 64.120430][ T996] ? __switch_to_asm+0x33/0x70
[ 64.125246][ T996] ? __pfx_kthread+0x10/0x10
[ 64.129847][ T996] ret_from_fork_asm+0x1a/0x30
[ 64.134698][ T996]
[ 64.137730][ T996] Kernel panic - not syncing: kernel: panic_on_warn set ...
[ 64.144993][ T996] CPU: 1 UID: 0 PID: 996 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(full)
[ 64.154347][ T996] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
[ 64.164388][ T996] Workqueue: writeback wb_workfn (flush-8:0)
[ 64.170380][ T996] Call Trace:
[ 64.173643][ T996]
[ 64.176556][ T996] dump_stack_lvl+0x99/0x250
[ 64.181129][ T996] ? __asan_memcpy+0x40/0x70
[ 64.185696][ T996] ? __pfx_dump_stack_lvl+0x10/0x10
[ 64.190870][ T996] ? __pfx__printk+0x10/0x10
[ 64.195457][ T996] vpanic+0x229/0x6d0
[ 64.199428][ T996] ? __pfx_vpanic+0x10/0x10
[ 64.203914][ T996] ? is_bpf_text_address+0x292/0x2b0
[ 64.209186][ T996] ? is_bpf_text_address+0x26/0x2b0
[ 64.214379][ T996] panic+0xb9/0xc0
[ 64.218109][ T996] ? __pfx_panic+0x10/0x10
[ 64.222518][ T996] ? ret_from_fork_asm+0x1a/0x30
[ 64.227445][ T996] __warn+0x334/0x4c0
[ 64.231415][ T996] ? __folio_start_writeback+0x8e7/0xa50
[ 64.237037][ T996] ? __folio_start_writeback+0x8e7/0xa50
[ 64.242654][ T996] report_bug+0x2be/0x4f0
[ 64.246976][ T996] ? __folio_start_writeback+0x8e7/0xa50
[ 64.252596][ T996] ? __folio_start_writeback+0x8e7/0xa50
[ 64.258214][ T996] ? __folio_start_writeback+0x8e9/0xa50
[ 64.263833][ T996] handle_bug+0x84/0x160
[ 64.268059][ T996] exc_invalid_op+0x1a/0x50
[ 64.272546][ T996] asm_exc_invalid_op+0x1a/0x20
[ 64.277397][ T996] RIP: 0010:__folio_start_writeback+0x8e7/0xa50
[ 64.283633][ T996] Code: 8b 05 2d 17 c8 10 48 3b 84 24 20 01 00 00 75 3b 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 10 5d 88 09 cc e8 1a fa c5 ff 90 <0f> 0b 90 e9 e5 fb ff ff e8 0c fa c5 ff 48 c7 c7 20 ff 3f 8e 4c 89
[ 64.303244][ T996] RSP: 0018:ffffc90003806ea0 EFLAGS: 00010293
[ 64.309301][ T996] RAX: ffffffff81fab916 RBX: ffffea0000931400 RCX: ffff888025e01e00
[ 64.317408][ T996] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 64.325369][ T996] RBP: ffffc90003807010 R08: ffffc90003806f97 R09: 0000000000000000
[ 64.333329][ T996] R10: ffffc90003806f80 R11: fffff52000700df3 R12: ffffea0000931408
[ 64.341286][ T996] R13: 0000000000000000 R14: ffff888148c5cd80 R15: ffff888148c5cb60
[ 64.349253][ T996] ? __folio_start_writeback+0x8e6/0xa50
[ 64.354903][ T996] ? __pfx___folio_start_writeback+0x10/0x10
[ 64.360873][ T996] ? __pfx_folio_clear_dirty_for_io+0x10/0x10
[ 64.367039][ T996] ? irqentry_exit+0x74/0x90
[ 64.371622][ T996] __block_write_full_folio+0x75f/0xe10
[ 64.377158][ T996] ? __pfx_blkdev_get_block+0x10/0x10
[ 64.382522][ T996] blkdev_writepages+0xd1/0x170
[ 64.387366][ T996] ? __pfx_blkdev_writepages+0x10/0x10
[ 64.392822][ T996] ? __pfx_blkdev_writepages+0x10/0x10
[ 64.398265][ T996] do_writepages+0x32e/0x550
[ 64.402857][ T996] __writeback_single_inode+0x145/0xff0
[ 64.408391][ T996] ? wbc_attach_and_unlock_inode+0x3f0/0x5d0
[ 64.414358][ T996] writeback_sb_inodes+0x6c7/0x1010
[ 64.419564][ T996] ? __pfx_writeback_sb_inodes+0x10/0x10
[ 64.425643][ T996] ? __pfx_down_read_trylock+0x10/0x10
[ 64.431088][ T996] ? __pfx___up_read+0x10/0x10
[ 64.436020][ T996] __writeback_inodes_wb+0x111/0x240
[ 64.441307][ T996] wb_writeback+0x44f/0xaf0
[ 64.445897][ T996] ? queue_io+0x321/0x590
[ 64.450218][ T996] ? __pfx_wb_writeback+0x10/0x10
[ 64.455245][ T996] wb_workfn+0xaef/0xef0
[ 64.459485][ T996] ? __pfx_wb_workfn+0x10/0x10
[ 64.464235][ T996] ? __lock_acquire+0xab9/0xd20
[ 64.469088][ T996] ? process_scheduled_works+0x9ef/0x17b0
[ 64.474800][ T996] ? _raw_spin_unlock_irq+0x23/0x50
[ 64.479986][ T996] ? process_scheduled_works+0x9ef/0x17b0
[ 64.485697][ T996] ? process_scheduled_works+0x9ef/0x17b0
[ 64.491405][ T996] process_scheduled_works+0xade/0x17b0
[ 64.496964][ T996] ? __pfx_process_scheduled_works+0x10/0x10
[ 64.502950][ T996] worker_thread+0x8a0/0xda0
[ 64.507620][ T996] ? __pfx__raw_spin_unlock_irqrestore+0x10/0x10
[ 64.513945][ T996] ? __kthread_parkme+0x7b/0x200
[ 64.518890][ T996] kthread+0x70e/0x8a0
[ 64.522953][ T996] ? __pfx_worker_thread+0x10/0x10
[ 64.528046][ T996] ? __pfx_kthread+0x10/0x10
[ 64.532623][ T996] ? _raw_spin_unlock_irq+0x23/0x50
[ 64.537808][ T996] ? lockdep_hardirqs_on+0x9c/0x150
[ 64.543075][ T996] ? __pfx_kthread+0x10/0x10
[ 64.547649][ T996] ret_from_fork+0x47c/0x820
[ 64.552232][ T996] ? __pfx_ret_from_fork+0x10/0x10
[ 64.557335][ T996] ? __switch_to_asm+0x39/0x70
[ 64.562086][ T996] ? __switch_to_asm+0x33/0x70
[ 64.566834][ T996] ? __pfx_kthread+0x10/0x10
[ 64.571499][ T996] ret_from_fork_asm+0x1a/0x30
[ 64.576264][ T996]
[ 64.581038][ T996] Kernel Offset: disabled
[ 64.585377][ T996] Rebooting in 86400 seconds..