syzbot

 do_exit+0x88e/0x23c0 kernel/exit.c:870
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
 get_signal+0x12fc/0x1400 kernel/signal.c:2902
 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
page has been migrated, last migrate reason: mempolicy_mbind
------------[ cut here ]------------
kernel BUG at mm/filemap.c:155!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 16752 Comm: syz.5.2162 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:filemap_unaccount_folio+0x704/0xc60 mm/filemap.c:155
Code: 48 25 ff 0f 00 00 0f 84 ec 00 00 00 e8 f5 b0 d2 ff e9 74 f9 ff ff e8 eb b0 d2 ff 48 89 df 48 c7 c6 20 24 b3 8a e8 dc 72 12 00 <0f> 0b e8 d5 b0 d2 ff 48 89 df 48 c7 c6 a0 29 b3 8a e8 c6 72 12 00
RSP: 0018:ffffc90003ab73b8 EFLAGS: 00010046
RAX: 59032e437ce04800 RBX: ffffea00012b8000 RCX: 59032e437ce04800
RDX: 0000000000000005 RSI: ffffffff8aaace20 RDI: ffffffff8afc71c0
RBP: ffffc90003ab7518 R08: ffffffff8e4a91af R09: 1ffffffff1c95235
R10: dffffc0000000000 R11: fffffbfff1c95236 R12: 0000000000000040
R13: 1ffffd4000257000 R14: 1ffffd4000257001 R15: ffffea00012b8008
FS:  00007fbd0c9746c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffffd CR3: 0000000066832000 CR4: 00000000003526e0
Call Trace:
 <TASK>
 __filemap_remove_folio+0xc4/0x7f0 mm/filemap.c:224
 filemap_remove_folio+0xf1/0x2c0 mm/filemap.c:257
 hugetlb_delete_from_page_cache fs/hugetlbfs/inode.c:433 [inline]
 remove_inode_single_folio fs/hugetlbfs/inode.c:638 [inline]
 remove_inode_hugepages+0x5dc/0x1870 fs/hugetlbfs/inode.c:696
 hugetlbfs_punch_hole fs/hugetlbfs/inode.c:816 [inline]
 hugetlbfs_fallocate+0xd45/0x1090 fs/hugetlbfs/inode.c:842
 vfs_fallocate+0x58e/0x700 fs/open.c:324
 madvise_remove mm/madvise.c:1007 [inline]
 madvise_vma_behavior mm/madvise.c:1031 [inline]
 madvise_walk_vmas mm/madvise.c:1266 [inline]
 do_madvise+0x15fe/0x3710 mm/madvise.c:1446
 __do_sys_madvise mm/madvise.c:1459 [inline]
 __se_sys_madvise mm/madvise.c:1457 [inline]
 __x64_sys_madvise+0xa6/0xc0 mm/madvise.c:1457
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbd0bb8eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbd0c974038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007fbd0bde6180 RCX: 00007fbd0bb8eec9
RDX: 0000000000000009 RSI: 0000000000600002 RDI: 0000200000000000
RBP: 00007fbd0bc11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbd0bde6218 R14: 00007fbd0bde6180 R15: 00007fff4dfea648
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:filemap_unaccount_folio+0x704/0xc60 mm/filemap.c:155
Code: 48 25 ff 0f 00 00 0f 84 ec 00 00 00 e8 f5 b0 d2 ff e9 74 f9 ff ff e8 eb b0 d2 ff 48 89 df 48 c7 c6 20 24 b3 8a e8 dc 72 12 00 <0f> 0b e8 d5 b0 d2 ff 48 89 df 48 c7 c6 a0 29 b3 8a e8 c6 72 12 00
RSP: 0018:ffffc90003ab73b8 EFLAGS: 00010046
RAX: 59032e437ce04800 RBX: ffffea00012b8000 RCX: 59032e437ce04800
RDX: 0000000000000005 RSI: ffffffff8aaace20 RDI: ffffffff8afc71c0
RBP: ffffc90003ab7518 R08: ffffffff8e4a91af R09: 1ffffffff1c95235
R10: dffffc0000000000 R11: fffffbfff1c95236 R12: 0000000000000040
R13: 1ffffd4000257000 R14: 1ffffd4000257001 R15: ffffea00012b8008
FS:  00007fbd0c9746c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffffd CR3: 0000000066832000 CR4: 00000000003526e0