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Date: Sat, 09 Mar 2024 03:25:33 -0800
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Subject: [syzbot] [mm?] WARNING in try_to_migrate_one (2)
From: syzbot <syzbot+ddf4b4c0005944105a9e@syzkaller.appspotmail.com>
To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, 
	linux-mm@kvack.org, syzkaller-bugs@googlegroups.com
Content-Type: text/plain; charset="UTF-8"

Hello,

syzbot found the following issue on:

HEAD commit:    3aaa8ce7a335 Merge tag 'mm-hotfixes-stable-2024-03-07-16-1..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1289abde180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=74a95eee532b237a
dashboard link: https://syzkaller.appspot.com/bug?extid=ddf4b4c0005944105a9e
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-3aaa8ce7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/84038f5e2c04/vmlinux-3aaa8ce7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/dc9d60eea301/bzImage-3aaa8ce7.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ddf4b4c0005944105a9e@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 2 PID: 43 at arch/x86/include/asm/pgtable.h:404 pte_uffd_wp arch/x86/include/asm/pgtable.h:404 [inline]
WARNING: CPU: 2 PID: 43 at arch/x86/include/asm/pgtable.h:404 try_to_migrate_one+0x19d4/0x36b0 mm/rmap.c:2256
Modules linked in:
CPU: 2 PID: 43 Comm: kcompactd0 Not tainted 6.8.0-rc7-syzkaller-00142-g3aaa8ce7a335 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:pte_uffd_wp arch/x86/include/asm/pgtable.h:404 [inline]
RIP: 0010:try_to_migrate_one+0x19d4/0x36b0 mm/rmap.c:2256
Code: 89 e7 e8 4f dd 0e 00 e9 16 f8 ff ff e8 d5 47 b4 ff 31 ff 4c 89 ee e8 db 42 b4 ff 4d 85 ed 0f 84 e4 09 00 00 e8 bd 47 b4 ff 90 <0f> 0b 90 e8 b4 47 b4 ff 48 83 cd 04 e9 65 f7 ff ff e8 a6 47 b4 ff
RSP: 0018:ffffc9000069f330 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffea0000a02d80 RCX: ffffffff81d79d15
RDX: ffff888018728000 RSI: ffffffff81d79d23 RDI: 0000000000000007
RBP: d7ffe7fffafe9202 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000003 R12: 0000000000000400
R13: 0000000000000002 R14: dffffc0000000000 R15: 0000000000000800
FS:  0000000000000000(0000) GS:ffff88802c400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00f07b020 CR3: 000000000d378000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rmap_walk_anon+0x228/0x580 mm/rmap.c:2599
 rmap_walk mm/rmap.c:2676 [inline]
 rmap_walk mm/rmap.c:2671 [inline]
 try_to_migrate+0x2ba/0x300 mm/rmap.c:2328
 migrate_folio_unmap mm/migrate.c:1244 [inline]
 migrate_pages_batch+0x10c7/0x2c60 mm/migrate.c:1675
 migrate_pages_sync mm/migrate.c:1841 [inline]
 migrate_pages+0x1b31/0x27d0 mm/migrate.c:1950
 compact_zone+0x1dcb/0x3f90 mm/compaction.c:2554
 proactive_compact_node+0x118/0x1d0 mm/compaction.c:2814
 kcompactd+0x712/0xd80 mm/compaction.c:3130
 kthread+0x2c6/0x3b0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243
 </TASK>


---
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