* [syzbot] [mm?] WARNING in set_mm_walk
@ 2026-08-11 0:13 syzbot
2026-08-11 0:48 ` Andrew Morton
0 siblings, 1 reply; 4+ messages in thread
From: syzbot @ 2026-08-11 0:13 UTC (permalink / raw)
To: akpm, axelrasmussen, baohua, david, hannes, kasong, linux-kernel,
linux-mm, ljs, mhocko, qi.zheng, shakeel.butt, syzkaller-bugs,
weixugc, yuanchu
Hello,
syzbot found the following issue on:
HEAD commit: 562bfb501c54 Merge tag 'integrity-v7.2-rc7' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11a8cbb9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=12ee2725d5fde63a9c96
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-562bfb50.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9cbf6ef0490e/vmlinux-562bfb50.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7ee52864c79a/bzImage-562bfb50.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+12ee2725d5fde63a9c96@syzkaller.appspotmail.com
------------[ cut here ]------------
current_is_kswapd()
WARNING: mm/vmscan.c:3800 at set_mm_walk+0x210/0x270 mm/vmscan.c:3800, CPU#1: kswapd0/110
Modules linked in:
CPU: 1 UID: 0 PID: 110 Comm: kswapd0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:set_mm_walk+0x210/0x270 mm/vmscan.c:3800
Code: 13 00 00 4d 8d 7d 08 e9 f7 fe ff ff e8 79 f5 2a 00 e9 b7 fe ff ff e8 7f 6b ba ff 90 0f 0b 90 e9 d2 fe ff ff e8 71 6b ba ff 90 <0f> 0b 90 e9 74 ff ff ff 4c 89 ff e8 80 f5 2a 00 e9 4e fe ff ff 48
RSP: 0018:ffffc900027772b8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888024934a80 RCX: ffffffff824ff8e8
RDX: ffff888024934a80 RSI: ffffffff824ff96f RDI: ffff888024934a80
RBP: 0000000000020000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000020000 R11: 0000000000000000 R12: 0000000000000000
R13: ffffc90002777c38 R14: 0000000000000001 R15: ffffc90002777c40
FS: 0000000000000000(0000) GS:ffff8880d5ed8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31923ffc CR3: 0000000109695000 CR4: 0000000000352ef0
DR0: 0000000000000005 DR1: 0000000000000005 DR2: 0000000020040004
DR3: 0000000000000056 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
try_to_inc_max_seq+0xf0/0x1090 mm/vmscan.c:4023
try_to_shrink_lruvec+0x4bd/0x6b0 mm/vmscan.c:4977
lru_gen_shrink_lruvec mm/vmscan.c:5128 [inline]
shrink_lruvec+0x31e/0x25b0 mm/vmscan.c:5888
mem_cgroup_shrink_node+0x227/0x6a0 mm/vmscan.c:6753
mem_cgroup_soft_reclaim mm/memcontrol-v1.c:312 [inline]
memcg1_soft_limit_reclaim+0x2d5/0x830 mm/memcontrol-v1.c:362
balance_pgdat+0xa11/0x1f00 mm/vmscan.c:7177
kswapd+0x556/0xb50 mm/vmscan.c:7462
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] [mm?] WARNING in set_mm_walk
2026-08-11 0:13 [syzbot] [mm?] WARNING in set_mm_walk syzbot
@ 2026-08-11 0:48 ` Andrew Morton
2026-08-11 4:39 ` Shakeel Butt
0 siblings, 1 reply; 4+ messages in thread
From: Andrew Morton @ 2026-08-11 0:48 UTC (permalink / raw)
To: syzbot
Cc: axelrasmussen, baohua, david, hannes, kasong, linux-kernel,
linux-mm, ljs, mhocko, qi.zheng, shakeel.butt, syzkaller-bugs,
weixugc, yuanchu
On Mon, 10 Aug 2026 17:13:29 -0700 syzbot <syzbot+12ee2725d5fde63a9c96@syzkaller.appspotmail.com> wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 562bfb501c54 Merge tag 'integrity-v7.2-rc7' of git://git.k..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=11a8cbb9580000
> kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
> dashboard link: https://syzkaller.appspot.com/bug?extid=12ee2725d5fde63a9c96
> compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
Thanks. One for the MGLRU develoeprs, it seems.
https://share.gemini.google/Wg4a5ns7E0LF might save a bit of time figuring this out.
> Unfortunately, I don't have any reproducer for this issue yet.
>
> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-562bfb50.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/9cbf6ef0490e/vmlinux-562bfb50.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/7ee52864c79a/bzImage-562bfb50.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+12ee2725d5fde63a9c96@syzkaller.appspotmail.com
>
> ------------[ cut here ]------------
> current_is_kswapd()
> WARNING: mm/vmscan.c:3800 at set_mm_walk+0x210/0x270 mm/vmscan.c:3800, CPU#1: kswapd0/110
>
> Modules linked in:
> CPU: 1 UID: 0 PID: 110 Comm: kswapd0 Tainted: G L syzkaller #0 PREEMPT(full)
> Tainted: [L]=SOFTLOCKUP
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
> RIP: 0010:set_mm_walk+0x210/0x270 mm/vmscan.c:3800
> Code: 13 00 00 4d 8d 7d 08 e9 f7 fe ff ff e8 79 f5 2a 00 e9 b7 fe ff ff e8 7f 6b ba ff 90 0f 0b 90 e9 d2 fe ff ff e8 71 6b ba ff 90 <0f> 0b 90 e9 74 ff ff ff 4c 89 ff e8 80 f5 2a 00 e9 4e fe ff ff 48
> RSP: 0018:ffffc900027772b8 EFLAGS: 00010293
> RAX: 0000000000000000 RBX: ffff888024934a80 RCX: ffffffff824ff8e8
> RDX: ffff888024934a80 RSI: ffffffff824ff96f RDI: ffff888024934a80
> RBP: 0000000000020000 R08: 0000000000000005 R09: 0000000000000000
> R10: 0000000000020000 R11: 0000000000000000 R12: 0000000000000000
> R13: ffffc90002777c38 R14: 0000000000000001 R15: ffffc90002777c40
> FS: 0000000000000000(0000) GS:ffff8880d5ed8000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000001b31923ffc CR3: 0000000109695000 CR4: 0000000000352ef0
> DR0: 0000000000000005 DR1: 0000000000000005 DR2: 0000000020040004
> DR3: 0000000000000056 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> Call Trace:
> <TASK>
> try_to_inc_max_seq+0xf0/0x1090 mm/vmscan.c:4023
> try_to_shrink_lruvec+0x4bd/0x6b0 mm/vmscan.c:4977
> lru_gen_shrink_lruvec mm/vmscan.c:5128 [inline]
> shrink_lruvec+0x31e/0x25b0 mm/vmscan.c:5888
> mem_cgroup_shrink_node+0x227/0x6a0 mm/vmscan.c:6753
> mem_cgroup_soft_reclaim mm/memcontrol-v1.c:312 [inline]
> memcg1_soft_limit_reclaim+0x2d5/0x830 mm/memcontrol-v1.c:362
> balance_pgdat+0xa11/0x1f00 mm/vmscan.c:7177
> kswapd+0x556/0xb50 mm/vmscan.c:7462
> kthread+0x370/0x450 kernel/kthread.c:436
> ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
> </TASK>
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want to overwrite report's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
>
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] [mm?] WARNING in set_mm_walk
2026-08-11 0:48 ` Andrew Morton
@ 2026-08-11 4:39 ` Shakeel Butt
2026-08-11 7:36 ` Lorenzo Stoakes (ARM)
0 siblings, 1 reply; 4+ messages in thread
From: Shakeel Butt @ 2026-08-11 4:39 UTC (permalink / raw)
To: Andrew Morton
Cc: syzbot, axelrasmussen, baohua, david, hannes, kasong,
linux-kernel, linux-mm, ljs, mhocko, qi.zheng, syzkaller-bugs,
weixugc, yuanchu
On Mon, Aug 10, 2026 at 05:48:52PM -0700, Andrew Morton wrote:
> On Mon, 10 Aug 2026 17:13:29 -0700 syzbot <syzbot+12ee2725d5fde63a9c96@syzkaller.appspotmail.com> wrote:
>
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit: 562bfb501c54 Merge tag 'integrity-v7.2-rc7' of git://git.k..
> > git tree: upstream
> > console output: https://syzkaller.appspot.com/x/log.txt?x=11a8cbb9580000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
> > dashboard link: https://syzkaller.appspot.com/bug?extid=12ee2725d5fde63a9c96
> > compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
>
> Thanks. One for the MGLRU develoeprs, it seems.
>
> https://share.gemini.google/Wg4a5ns7E0LF might save a bit of time figuring this out.
>
This is memcg-v1's soft limit which is deprecated. I am more inclined to simply
remove this code instead of fixing it.
I will take a stab at removal.
> > Unfortunately, I don't have any reproducer for this issue yet.
> >
> > Downloadable assets:
> > disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-562bfb50.raw.xz
> > vmlinux: https://storage.googleapis.com/syzbot-assets/9cbf6ef0490e/vmlinux-562bfb50.xz
> > kernel image: https://storage.googleapis.com/syzbot-assets/7ee52864c79a/bzImage-562bfb50.xz
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+12ee2725d5fde63a9c96@syzkaller.appspotmail.com
> >
> > ------------[ cut here ]------------
> > current_is_kswapd()
> > WARNING: mm/vmscan.c:3800 at set_mm_walk+0x210/0x270 mm/vmscan.c:3800, CPU#1: kswapd0/110
> >
> > Modules linked in:
> > CPU: 1 UID: 0 PID: 110 Comm: kswapd0 Tainted: G L syzkaller #0 PREEMPT(full)
> > Tainted: [L]=SOFTLOCKUP
> > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
> > RIP: 0010:set_mm_walk+0x210/0x270 mm/vmscan.c:3800
> > Code: 13 00 00 4d 8d 7d 08 e9 f7 fe ff ff e8 79 f5 2a 00 e9 b7 fe ff ff e8 7f 6b ba ff 90 0f 0b 90 e9 d2 fe ff ff e8 71 6b ba ff 90 <0f> 0b 90 e9 74 ff ff ff 4c 89 ff e8 80 f5 2a 00 e9 4e fe ff ff 48
> > RSP: 0018:ffffc900027772b8 EFLAGS: 00010293
> > RAX: 0000000000000000 RBX: ffff888024934a80 RCX: ffffffff824ff8e8
> > RDX: ffff888024934a80 RSI: ffffffff824ff96f RDI: ffff888024934a80
> > RBP: 0000000000020000 R08: 0000000000000005 R09: 0000000000000000
> > R10: 0000000000020000 R11: 0000000000000000 R12: 0000000000000000
> > R13: ffffc90002777c38 R14: 0000000000000001 R15: ffffc90002777c40
> > FS: 0000000000000000(0000) GS:ffff8880d5ed8000(0000) knlGS:0000000000000000
> > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 0000001b31923ffc CR3: 0000000109695000 CR4: 0000000000352ef0
> > DR0: 0000000000000005 DR1: 0000000000000005 DR2: 0000000020040004
> > DR3: 0000000000000056 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> > Call Trace:
> > <TASK>
> > try_to_inc_max_seq+0xf0/0x1090 mm/vmscan.c:4023
> > try_to_shrink_lruvec+0x4bd/0x6b0 mm/vmscan.c:4977
> > lru_gen_shrink_lruvec mm/vmscan.c:5128 [inline]
> > shrink_lruvec+0x31e/0x25b0 mm/vmscan.c:5888
> > mem_cgroup_shrink_node+0x227/0x6a0 mm/vmscan.c:6753
> > mem_cgroup_soft_reclaim mm/memcontrol-v1.c:312 [inline]
> > memcg1_soft_limit_reclaim+0x2d5/0x830 mm/memcontrol-v1.c:362
> > balance_pgdat+0xa11/0x1f00 mm/vmscan.c:7177
> > kswapd+0x556/0xb50 mm/vmscan.c:7462
> > kthread+0x370/0x450 kernel/kthread.c:436
> > ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
> > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
> > </TASK>
> >
> >
> > ---
> > This report is generated by a bot. It may contain errors.
> > See https://goo.gl/tpsmEJ for more information about syzbot.
> > syzbot engineers can be reached at syzkaller@googlegroups.com.
> >
> > syzbot will keep track of this issue. See:
> > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> >
> > If the report is already addressed, let syzbot know by replying with:
> > #syz fix: exact-commit-title
> >
> > If you want to overwrite report's subsystems, reply with:
> > #syz set subsystems: new-subsystem
> > (See the list of subsystem names on the web dashboard)
> >
> > If the report is a duplicate of another one, reply with:
> > #syz dup: exact-subject-of-another-report
> >
> > If you want to undo deduplication, reply with:
> > #syz undup
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] [mm?] WARNING in set_mm_walk
2026-08-11 4:39 ` Shakeel Butt
@ 2026-08-11 7:36 ` Lorenzo Stoakes (ARM)
0 siblings, 0 replies; 4+ messages in thread
From: Lorenzo Stoakes (ARM) @ 2026-08-11 7:36 UTC (permalink / raw)
To: Shakeel Butt
Cc: Andrew Morton, syzbot, axelrasmussen, baohua, david, hannes,
kasong, linux-kernel, linux-mm, mhocko, qi.zheng, syzkaller-bugs,
weixugc, yuanchu
On Mon, Aug 10, 2026 at 09:39:08PM -0700, Shakeel Butt wrote:
> This is memcg-v1's soft limit which is deprecated. I am more inclined to simply
> remove this code instead of fixing it.
Love it :)
The best code is no code (sadly we have to have _some_ code :)
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2026-08-11 7:36 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2026-08-11 0:13 [syzbot] [mm?] WARNING in set_mm_walk syzbot
2026-08-11 0:48 ` Andrew Morton
2026-08-11 4:39 ` Shakeel Butt
2026-08-11 7:36 ` Lorenzo Stoakes (ARM)
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