Hello, syzbot found the following issue on: HEAD commit: 7d730f1bf6f3 Add linux-next specific files for 20231005 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1716036e680000 kernel config: https://syzkaller.appspot.com/x/.config?x=f532286be4fff4b5 dashboard link: https://syzkaller.appspot.com/bug?extid=831ba898b5db8d5617ea compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/1d7f28a4398f/disk-7d730f1b.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d454d124268e/vmlinux-7d730f1b.xz kernel image: https://storage.googleapis.com/syzbot-assets/dbca966175cb/bzImage-7d730f1b.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+831ba898b5db8d5617ea@xxxxxxxxxxxxxxxxxxxxxxxxx kernel_init+0x1c/0x2a0 init/main.c:1437 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 5208 at mm/memcontrol.c:7552 mem_cgroup_migrate+0x2fa/0x390 mm/memcontrol.c:7552 Modules linked in: CPU: 1 PID: 5208 Comm: syz-executor.1 Not tainted 6.6.0-rc4-next-20231005-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 RIP: 0010:mem_cgroup_migrate+0x2fa/0x390 mm/memcontrol.c:7552 Code: f7 ff e9 36 ff ff ff 80 3d 84 b2 d1 0c 00 0f 85 54 ff ff ff 48 c7 c6 a0 9e 9b 8a 48 89 ef e8 0d 5c df ff c6 05 68 b2 d1 0c 01 <0f> 0b e9 37 ff ff ff 48 c7 c6 e0 9a 9b 8a 48 89 df e8 f0 5b df ff RSP: 0018:ffffc90004b2fa38 EFLAGS: 00010246 RAX: 0000000000040000 RBX: ffffea0005338000 RCX: ffffc90005439000 RDX: 0000000000040000 RSI: ffffffff81e76463 RDI: ffffffff8ae96da0 RBP: ffffea0001d98000 R08: 0000000000000000 R09: fffffbfff1d9db9a R10: ffffffff8ecedcd7 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000200 R14: 0000000000000000 R15: ffffea0001d98018 FS: 00007fc15e89d6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31820000 CR3: 000000007f5e1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> hugetlbfs_migrate_folio fs/hugetlbfs/inode.c:1066 [inline] hugetlbfs_migrate_folio+0xd0/0x120 fs/hugetlbfs/inode.c:1049 move_to_new_folio+0x183/0x690 mm/migrate.c:966 unmap_and_move_huge_page mm/migrate.c:1428 [inline] migrate_hugetlbs mm/migrate.c:1546 [inline] migrate_pages+0x16ac/0x27c0 mm/migrate.c:1900 migrate_to_node mm/mempolicy.c:1072 [inline] do_migrate_pages+0x43e/0x690 mm/mempolicy.c:1171 kernel_migrate_pages+0x59b/0x780 mm/mempolicy.c:1682 __do_sys_migrate_pages mm/mempolicy.c:1700 [inline] __se_sys_migrate_pages mm/mempolicy.c:1696 [inline] __x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1696 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fc15da7cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc15e89d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000100 RAX: ffffffffffffffda RBX: 00007fc15db9bf80 RCX: 00007fc15da7cae9 RDX: 0000000020000340 RSI: 0000000000000080 RDI: 0000000000000000 RBP: 00007fc15dac847a R08: 0000000000000000 R09: 0000000000000000 R10: 00000000200003c0 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fc15db9bf80 R15: 00007ffd87d7c058 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup