Re: [syzbot] [mm?] WARNING in page_vma_mapped_walk

From: syzbot
Date: Wed Oct 04 2023 - 00:37:48 EST


syzbot has found a reproducer for the following issue on:

HEAD commit: c9f2baaa18b5 Add linux-next specific files for 20231003
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=17bbfb06680000
kernel config: https://syzkaller.appspot.com/x/.config?x=3fe9c462fee1649f
dashboard link: https://syzkaller.appspot.com/bug?extid=dcf3f48f4bfe47a2f80a
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1421389a680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12860a7c680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5361e41384fe/disk-c9f2baaa.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7028b209124d/vmlinux-c9f2baaa.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a167dc667ee5/bzImage-c9f2baaa.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dcf3f48f4bfe47a2f80a@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 0 PID: 5058 at include/linux/hugetlb.h:1289 hugetlb_walk include/linux/hugetlb.h:1289 [inline]
WARNING: CPU: 0 PID: 5058 at include/linux/hugetlb.h:1289 page_vma_mapped_walk+0x1eb6/0x27d0 mm/page_vma_mapped.c:199
Modules linked in:
CPU: 0 PID: 5058 Comm: syz-executor350 Not tainted 6.6.0-rc4-next-20231003-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:hugetlb_walk include/linux/hugetlb.h:1289 [inline]
RIP: 0010:page_vma_mapped_walk+0x1eb6/0x27d0 mm/page_vma_mapped.c:199
Code: 00 be ff ff ff ff 48 81 c7 a0 01 00 00 e8 72 64 77 08 31 ff 89 c5 89 c6 e8 27 ac b9 ff 85 ed 0f 85 95 f6 ff ff e8 aa b0 b9 ff <0f> 0b e9 89 f6 ff ff e8 9e b0 b9 ff 48 89 ef 48 81 e7 00 f0 ff ff
RSP: 0018:ffffc90003a5f6c0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88802184b310 RCX: ffffffff81cea839
RDX: ffff88801d870000 RSI: ffffffff81cea846 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000009 R12: 0000000000200000
R13: ffffffff92315af8 R14: ffffc90003a5f8c0 R15: ffffffff92315b90
FS: 00005555564ba380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000080 CR3: 0000000078ecd000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
try_to_migrate_one+0x4a2/0x28b0 mm/rmap.c:1950
rmap_walk_anon+0x225/0x570 mm/rmap.c:2522
rmap_walk mm/rmap.c:2599 [inline]
rmap_walk mm/rmap.c:2594 [inline]
try_to_migrate+0x2b6/0x300 mm/rmap.c:2251
unmap_and_move_huge_page mm/migrate.c:1421 [inline]
migrate_hugetlbs mm/migrate.c:1547 [inline]
migrate_pages+0xa42/0x27c0 mm/migrate.c:1901
migrate_to_node mm/mempolicy.c:1097 [inline]
do_migrate_pages+0x2e9/0x670 mm/mempolicy.c:1196
kernel_migrate_pages+0x59b/0x780 mm/mempolicy.c:1681
__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: 0033:0x7f7a6faa32e9
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffed8e03b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000100
RAX: ffffffffffffffda RBX: 00007ffed8e03d18 RCX: 00007f7a6faa32e9
RDX: 0000000020000000 RSI: 0000000000000004 RDI: 0000000000000000
RBP: 00007f7a6fb16610 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000080 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffed8e03d08 R14: 0000000000000001 R15: 0000000000000001
</TASK>


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