[syzbot] [mm?] WARNING in huge_pmd_unshare

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    df964ce9ef9f Add linux-next specific files for 20230929
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=134e2921680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=880c828d75e38e1b
dashboard link: https://syzkaller.appspot.com/bug?extid=ff00584717dadcbd2e67
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/fe7244c6057d/disk-df964ce9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/48cdc7f3b2c0/vmlinux-df964ce9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ce7c93a66da9/bzImage-df964ce9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ff00584717dadcbd2e67@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 1 PID: 7121 at mm/hugetlb.c:298 hugetlb_vma_assert_locked mm/hugetlb.c:298 [inline]
WARNING: CPU: 1 PID: 7121 at mm/hugetlb.c:298 huge_pmd_unshare+0x6be/0x940 mm/hugetlb.c:6904
Modules linked in:
CPU: 1 PID: 7121 Comm: syz-executor.1 Not tainted 6.6.0-rc3-next-20230929-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:hugetlb_vma_assert_locked mm/hugetlb.c:298 [inline]
RIP: 0010:huge_pmd_unshare+0x6be/0x940 mm/hugetlb.c:6904
Code: ff ff ff ff 48 81 c7 c8 00 00 00 e8 dc 89 6c 08 31 ff 41 89 c5 89 c6 e8 20 ce ae ff 45 85 ed 0f 85 67 fa ff ff e8 a2 d2 ae ff <0f> 0b e9 5b fa ff ff 31 db e9 5d fd ff ff e8 8f d2 ae ff 48 89 da
RSP: 0018:ffffc90016177678 EFLAGS: 00010283
RAX: 0000000000003492 RBX: 0000000020000000 RCX: ffffc9000aee4000
RDX: 0000000000040000 RSI: ffffffff81d9831e RDI: 0000000000000005
RBP: ffff88802a226880 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 000000000000003c R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: ffff88807e489e88
FS:  00007fde004546c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30d2a000 CR3: 000000007f0d7000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __unmap_hugepage_range+0x4e3/0x1940 mm/hugetlb.c:5222
 unmap_hugepage_range+0x1fa/0x330 mm/hugetlb.c:5347
 hugetlb_vmdelete_list+0x11d/0x170 fs/hugetlbfs/inode.c:534
 hugetlbfs_punch_hole fs/hugetlbfs/inode.c:734 [inline]
 hugetlbfs_fallocate+0xc75/0x1050 fs/hugetlbfs/inode.c:774
 shm_fallocate+0xca/0x110 ipc/shm.c:646
 vfs_fallocate+0x46c/0xe80 fs/open.c:324
 madvise_remove mm/madvise.c:1019 [inline]
 madvise_vma_behavior+0x1c00/0x1d00 mm/madvise.c:1043
 madvise_walk_vmas+0x1cf/0x2c0 mm/madvise.c:1278
 do_madvise+0x333/0x660 mm/madvise.c:1458
 __do_sys_madvise mm/madvise.c:1471 [inline]
 __se_sys_madvise mm/madvise.c:1469 [inline]
 __x64_sys_madvise+0xaa/0x110 mm/madvise.c:1469
 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: 0033:0x7fddff67cae9
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:00007fde004540c8 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007fddff79c050 RCX: 00007fddff67cae9
RDX: 0000000000000009 RSI: 000000000060000b RDI: 0000000020000000
RBP: 00007fddff6c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fddff79c050 R15: 00007ffce99d7b18
 </TASK>


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