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Date:   Mon, 06 Jun 2022 10:17:34 -0700
Message-ID: <000000000000db448c05e0caa5ba@google.com>
Subject: [syzbot] WARNING in register_shrinker_prepared
From:   syzbot <syzbot+300d27c79fe6d4cbcc39@syzkaller.appspotmail.com>
To:     akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, syzkaller-bugs@googlegroups.com
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Hello,

syzbot found the following issue on:

HEAD commit:    1cfd968b58a1 Add linux-next specific files for 20220603
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12f7b6b3f00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7da8386e3742814f
dashboard link: https://syzkaller.appspot.com/bug?extid=300d27c79fe6d4cbcc39
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=103e5177f00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=13545057f00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+300d27c79fe6d4cbcc39@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 20
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3694 at mm/vmscan.c:681 register_shrinker_prepared+0x119/0x150 mm/vmscan.c:681
Modules linked in:
CPU: 0 PID: 3694 Comm: syz-executor250 Not tainted 5.18.0-next-20220603-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:register_shrinker_prepared+0x119/0x150 mm/vmscan.c:681
Code: ff 89 c5 89 c6 e8 87 18 d1 ff 85 ed 75 17 e8 2e 1c d1 ff 5b 48 c7 c7 60 dd e7 8b 5d 41 5c 41 5d e9 6c d2 b3 ff e8 17 1c d1 ff <0f> 0b eb e0 e8 5e f7 1d 00 eb be 4c 89 e7 e8 e4 f7 1d 00 eb 81 e8
RSP: 0018:ffffc900030c7c80 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff8880238eba80 RSI: ffffffff81a965c9 RDI: 0000000000000005
RBP: 00000000fffffff4 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000fffffff4 R11: 0000000000000001 R12: ffff88807ebca7a0
R13: ffff8880770347a0 R14: ffffffff8c50df80 R15: ffff888011c82c00
FS:  000055555733f300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007effd0fd11d0 CR3: 00000000203c8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 sget+0x472/0x580 fs/super.c:631
 mount_bdev+0xf8/0x450 fs/super.c:1342
 legacy_get_tree+0x105/0x220 fs/fs_context.c:610
 vfs_get_tree+0x89/0x2f0 fs/super.c:1501
 do_new_mount fs/namespace.c:3040 [inline]
 path_mount+0x1320/0x1fa0 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount fs/namespace.c:3568 [inline]
 __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7effd0ff93fa
Code: 48 c7 c2 c0 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 a8 00 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffce9034038 EFLAGS: 00000286 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffce9034090 RCX: 00007effd0ff93fa
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffce9034050
RBP: 00007ffce9034050 R08: 00007ffce9034090 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000286 R12: 0000000020000218
R13: 0000000000000004 R14: 0000000000000005 R15: 0000000000000001
 </TASK>


---
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