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kernel BUG at fs/btrfs/extent-tree.c:3299!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 7123 Comm: syz.2.558 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : btrfs_free_tree_block+0xa50/0xa84 fs/btrfs/extent-tree.c:3299
lr : btrfs_free_tree_block+0xa50/0xa84 fs/btrfs/extent-tree.c:3299
sp : ffff800021246900
x29: ffff800021246a00 x28: ffff700004248d28 x27: ffff000000000005
x26: ffff800021246960 x25: 00000000fffffff4 x24: ffff0000dfc7b0a0
x23: 0000000000000001 x22: ffff000000000100 x21: ffff0000dfc7af88
x20: dfff800000000000 x19: ffff0000dfc7af80 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000082d92bc x15: 0000000000000000
x14: 0000000000000001 x13: 1ffff00002a9af86 x12: 0000000000ff0100
x11: ff00800009f390f8 x10: 0000000000000000 x9 : ffff800009f390f8
x8 : ffff0000d1399bc0 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800021245fd8 x4 : 00000000ffffffff x3 : 0000000000000c40
x2 : ffff0000cd334f00 x1 : 00000000fffffff4 x0 : 0000000000000000
Call trace:
 btrfs_free_tree_block+0xa50/0xa84 fs/btrfs/extent-tree.c:3299
 btrfs_force_cow_block+0xb30/0x188c fs/btrfs/ctree.c:505
 btrfs_cow_block+0x2d0/0x708 fs/btrfs/ctree.c:623
 btrfs_search_slot+0xa50/0x237c fs/btrfs/ctree.c:-1
 btrfs_lookup_file_extent+0xe4/0x144 fs/btrfs/file-item.c:253
 btrfs_drop_extents+0x358/0x22c8 fs/btrfs/file.c:243
 cow_file_range_inline+0x2b4/0x7a4 fs/btrfs/inode.c:437
 cow_file_range+0x2ec/0xbb8 fs/btrfs/inode.c:1223
 btrfs_run_delalloc_range+0x310/0xf0c fs/btrfs/inode.c:2237
 writepage_delalloc+0x11c/0x2f4 fs/btrfs/extent_io.c:1980
 __extent_writepage+0x528/0xc18 fs/btrfs/extent_io.c:2284
 extent_write_cache_pages fs/btrfs/extent_io.c:3198 [inline]
 extent_writepages+0x93c/0x1074 fs/btrfs/extent_io.c:3320
 btrfs_writepages+0x28/0x38 fs/btrfs/inode.c:8326
 do_writepages+0x2b0/0x504 mm/page-writeback.c:2491
 filemap_fdatawrite_wbc+0x124/0x174 mm/filemap.c:388
 __filemap_fdatawrite_range+0xcc/0x12c mm/filemap.c:421
 sync_file_range+0x1c8/0x284 fs/sync.c:292
 ksys_sync_file_range fs/sync.c:364 [inline]
 __do_sys_sync_file_range fs/sync.c:373 [inline]
 __se_sys_sync_file_range fs/sync.c:370 [inline]
 __arm64_sys_sync_file_range+0xc4/0x114 fs/sync.c:370
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: 17fffe90 9795c92b d4210000 9795c929 (d4210000) 
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