[syzbot] [mm?] WARNING in try_to_migrate_one

From: syzbot
Date: Wed Aug 02 2023 - 03:23:19 EST


syzbot found the following issue on:

HEAD commit: f837f0a3c948 Merge tag 'arm64-fixes' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12e64c61a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=5d10d93e1ae1f229
dashboard link: https://syzkaller.appspot.com/bug?extid=94d51f4b3c59cdad469d
compiler: Debian clang version 15.0.6, 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/b77423ff9f0c/disk-f837f0a3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fe98d65e37e8/vmlinux-f837f0a3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0ce03308abc6/bzImage-f837f0a3.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+94d51f4b3c59cdad469d@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 0 PID: 31 at arch/x86/include/asm/pgtable.h:314 try_to_migrate_one+0x19c5/0x2860 mm/rmap.c:2096
Modules linked in:
CPU: 0 PID: 31 Comm: kcompactd0 Not tainted 6.5.0-rc3-syzkaller-00225-gf837f0a3c948 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
RIP: 0010:pte_uffd_wp arch/x86/include/asm/pgtable.h:314 [inline]
RIP: 0010:try_to_migrate_one+0x19c5/0x2860 mm/rmap.c:2096
Code: 00 e8 6f 79 fe ff 84 c0 0f 84 1b 05 00 00 e8 d2 1b b6 ff e9 dc ee ff ff e8 c8 1b b6 ff 48 ff cb e9 a2 f3 ff ff e8 bb 1b b6 ff <0f> 0b e9 fa fa ff ff 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 59 ff
RSP: 0018:ffffc90000a7ede0 EFLAGS: 00010293
RAX: ffffffff81d5fa55 RBX: 0000000000000402 RCX: ffff8880136e3b80
RDX: 0000000000000000 RSI: 0000000000000402 RDI: 0000000000000402
RBP: ffffc90000a7f130 R08: ffffffff81d5f544 R09: 1ffffd4000179978
R10: dffffc0000000000 R11: fffff94000179979 R12: 0000000000000002
R13: ffffe7fffa19a000 R14: 000000002f32fc67 R15: d000000000000000
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f764abf5000 CR3: 0000000081a0e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rmap_walk_anon+0x388/0x6b0 mm/rmap.c:2441
migrate_folio_unmap mm/migrate.c:1233 [inline]
migrate_pages_batch+0x11c5/0x3840 mm/migrate.c:1658
migrate_pages_sync mm/migrate.c:1823 [inline]
migrate_pages+0x1e7c/0x3210 mm/migrate.c:1927
compact_zone+0x308f/0x4750 mm/compaction.c:2484
proactive_compact_node mm/compaction.c:2749 [inline]
kcompactd+0x1082/0x1b90 mm/compaction.c:3069
kthread+0x2b8/0x350 kernel/kthread.c:389
ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

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