[syzbot] [cgroups?] [mm?] WARNING in __mod_memcg_lruvec_state

[syzbot] [cgroups?] [mm?] WARNING in __mod_memcg_lruvec_state

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    317c7bc0ef03 Merge tag 'mmc-v6.9-rc1' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15fd40c5180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f64ec427e98bccd7
dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

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-317c7bc0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/efab473d72c0/vmlinux-317c7bc0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5ba3f56d362d/bzImage-317c7bc0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 30105 at mm/memcontrol.c:865 __mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
Modules linked in:
CPU: 0 PID: 30105 Comm: syz-executor.2 Not tainted 6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
Code: 45 85 e4 75 1d 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc b8 00 04 00 00 e9 80 fd ff ff 89 c6 e9 a0 fd ff ff 90 <0f> 0b 90 e9 a7 fc ff ff 48 c7 c7 18 43 e1 8f e8 32 51 f8 ff e9 5e
RSP: 0018:ffffc900034beef8 EFLAGS: 00010202
RAX: 0000000000000292 RBX: 0000000000000001 RCX: 1ffffffff1fc2863
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888024b92bc8
RBP: ffff888024b92000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801c326000 R14: 0000000000000001 R15: ffff888024b92000
FS:  00007f0811bf96c0(0000) GS:ffff88806b000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000cfff1dd CR3: 000000003e4e2000 CR4: 0000000000350ef0
DR0: 0000000000000031 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __update_lru_size include/linux/mm_inline.h:47 [inline]
 lru_gen_update_size include/linux/mm_inline.h:199 [inline]
 lru_gen_add_folio+0x62d/0xe80 include/linux/mm_inline.h:262
 lruvec_add_folio include/linux/mm_inline.h:323 [inline]
 lru_add_fn+0x3fc/0xd80 mm/swap.c:215
 folio_batch_move_lru+0x243/0x400 mm/swap.c:233
 lru_add_drain_cpu+0x534/0x860 mm/swap.c:667
 lru_add_drain+0x109/0x440 mm/swap.c:767
 __folio_batch_release+0x68/0xb0 mm/swap.c:1091
 folio_batch_release include/linux/pagevec.h:101 [inline]
 mpage_prepare_extent_to_map+0x112b/0x14b0 fs/ext4/inode.c:2505
 ext4_do_writepages+0xa9e/0x3250 fs/ext4/inode.c:2632
 ext4_writepages+0x303/0x730 fs/ext4/inode.c:2768
 do_writepages+0x1a3/0x7f0 mm/page-writeback.c:2612
 filemap_fdatawrite_wbc mm/filemap.c:397 [inline]
 filemap_fdatawrite_wbc+0x148/0x1c0 mm/filemap.c:387
 __filemap_fdatawrite_range+0xba/0x100 mm/filemap.c:430
 file_write_and_wait_range+0xd0/0x140 mm/filemap.c:788
 ext4_sync_file+0x296/0xf30 fs/ext4/fsync.c:158
 vfs_fsync_range+0x141/0x230 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2793 [inline]
 ext4_buffered_write_iter+0x2e6/0x3d0 fs/ext4/file.c:305
 ext4_file_write_iter+0x874/0x1a40 fs/ext4/file.c:698
 call_write_iter include/linux/fs.h:2108 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6db/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f0810e7dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0811bf90c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f0810fabf80 RCX: 00007f0810e7dda9
RDX: 0000000000002000 RSI: 0000000020000180 RDI: 0000000000000007
RBP: 00007f0810eca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f0810fabf80 R15: 00007ffd57bcc8d8
 </TASK>


---
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Re: [syzbot] [cgroups?] [mm?] WARNING in __mod_memcg_lruvec_state

[Andrew Morton]

On Tue, 02 Apr 2024 01:03:26 -0700 syzbot <syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com> wrote:

> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    317c7bc0ef03 Merge tag 'mmc-v6.9-rc1' of git://git.kernel...
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=15fd40c5180000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=f64ec427e98bccd7
> dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
> compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> 
> 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-317c7bc0.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/efab473d72c0/vmlinux-317c7bc0.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/5ba3f56d362d/bzImage-317c7bc0.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com
> 
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 30105 at mm/memcontrol.c:865 __mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
> Modules linked in:
> CPU: 0 PID: 30105 Comm: syz-executor.2 Not tainted 6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
> RIP: 0010:__mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
> Code: 45 85 e4 75 1d 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc b8 00 04 00 00 e9 80 fd ff ff 89 c6 e9 a0 fd ff ff 90 <0f> 0b 90 e9 a7 fc ff ff 48 c7 c7 18 43 e1 8f e8 32 51 f8 ff e9 5e
> RSP: 0018:ffffc900034beef8 EFLAGS: 00010202
> RAX: 0000000000000292 RBX: 0000000000000001 RCX: 1ffffffff1fc2863
> RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888024b92bc8
> RBP: ffff888024b92000 R08: 0000000000000005 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
> R13: ffff88801c326000 R14: 0000000000000001 R15: ffff888024b92000
> FS:  00007f0811bf96c0(0000) GS:ffff88806b000000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 000000000cfff1dd CR3: 000000003e4e2000 CR4: 0000000000350ef0
> DR0: 0000000000000031 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
>  <TASK>
>  __update_lru_size include/linux/mm_inline.h:47 [inline]
>  lru_gen_update_size include/linux/mm_inline.h:199 [inline]
>  lru_gen_add_folio+0x62d/0xe80 include/linux/mm_inline.h:262
>  lruvec_add_folio include/linux/mm_inline.h:323 [inline]
>  lru_add_fn+0x3fc/0xd80 mm/swap.c:215
>  folio_batch_move_lru+0x243/0x400 mm/swap.c:233

Well it beats me.  I assume we failed to update for a new case.  I'll
toss this into -next to perhaps shed a bit of light.

--- a/mm/memcontrol.c~__mod_memcg_lruvec_state-enhance-diagnostics
+++ a/mm/memcontrol.c
@@ -860,10 +860,12 @@ void __mod_memcg_lruvec_state(struct lru
 		case NR_ANON_THPS:
 		case NR_SHMEM_PMDMAPPED:
 		case NR_FILE_PMDMAPPED:
-			WARN_ON_ONCE(!in_task());
+			if (WARN_ON_ONCE(!in_task()))
+				pr_warn("stat item index: %d\n", idx);
 			break;
 		default:
-			VM_WARN_ON_IRQS_ENABLED();
+			if (VM_WARN_ON_IRQS_ENABLED())
+				pr_warn("stat item index: %d\n", idx);
 		}
 	}
 
_

Re: [syzbot] [cgroups?] [mm?] WARNING in __mod_memcg_lruvec_state

[Yosry Ahmed]

On Wed, Apr 3, 2024 at 6:08 PM Andrew Morton <akpm@linux-foundation.org> wrote:
>
> On Tue, 02 Apr 2024 01:03:26 -0700 syzbot <syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com> wrote:
>
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit:    317c7bc0ef03 Merge tag 'mmc-v6.9-rc1' of git://git.kernel...
> > git tree:       upstream
> > console output: https://syzkaller.appspot.com/x/log.txt?x=15fd40c5180000
> > kernel config:  https://syzkaller.appspot.com/x/.config?x=f64ec427e98bccd7
> > dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
> > compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> >
> > 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-317c7bc0.raw.xz
> > vmlinux: https://storage.googleapis.com/syzbot-assets/efab473d72c0/vmlinux-317c7bc0.xz
> > kernel image: https://storage.googleapis.com/syzbot-assets/5ba3f56d362d/bzImage-317c7bc0.xz
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com
> >
> > ------------[ cut here ]------------
> > WARNING: CPU: 0 PID: 30105 at mm/memcontrol.c:865 __mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
> > Modules linked in:
> > CPU: 0 PID: 30105 Comm: syz-executor.2 Not tainted 6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0
> > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
> > RIP: 0010:__mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
> > Code: 45 85 e4 75 1d 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc b8 00 04 00 00 e9 80 fd ff ff 89 c6 e9 a0 fd ff ff 90 <0f> 0b 90 e9 a7 fc ff ff 48 c7 c7 18 43 e1 8f e8 32 51 f8 ff e9 5e
> > RSP: 0018:ffffc900034beef8 EFLAGS: 00010202
> > RAX: 0000000000000292 RBX: 0000000000000001 RCX: 1ffffffff1fc2863
> > RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888024b92bc8
> > RBP: ffff888024b92000 R08: 0000000000000005 R09: 0000000000000000
> > R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
> > R13: ffff88801c326000 R14: 0000000000000001 R15: ffff888024b92000
> > FS:  00007f0811bf96c0(0000) GS:ffff88806b000000(0000) knlGS:0000000000000000
> > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 000000000cfff1dd CR3: 000000003e4e2000 CR4: 0000000000350ef0
> > DR0: 0000000000000031 DR1: 0000000000000000 DR2: 0000000000000000
> > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > Call Trace:
> >  <TASK>
> >  __update_lru_size include/linux/mm_inline.h:47 [inline]
> >  lru_gen_update_size include/linux/mm_inline.h:199 [inline]
> >  lru_gen_add_folio+0x62d/0xe80 include/linux/mm_inline.h:262
> >  lruvec_add_folio include/linux/mm_inline.h:323 [inline]
> >  lru_add_fn+0x3fc/0xd80 mm/swap.c:215
> >  folio_batch_move_lru+0x243/0x400 mm/swap.c:233
>
> Well it beats me.  I assume we failed to update for a new case.  I'll
> toss this into -next to perhaps shed a bit of light.
>
> --- a/mm/memcontrol.c~__mod_memcg_lruvec_state-enhance-diagnostics
> +++ a/mm/memcontrol.c
> @@ -860,10 +860,12 @@ void __mod_memcg_lruvec_state(struct lru
>                 case NR_ANON_THPS:
>                 case NR_SHMEM_PMDMAPPED:
>                 case NR_FILE_PMDMAPPED:
> -                       WARN_ON_ONCE(!in_task());
> +                       if (WARN_ON_ONCE(!in_task()))
> +                               pr_warn("stat item index: %d\n", idx);
>                         break;
>                 default:
> -                       VM_WARN_ON_IRQS_ENABLED();
> +                       if (VM_WARN_ON_IRQS_ENABLED())
> +                               pr_warn("stat item index: %d\n", idx);

Line 865 from this commit should be this warning (i.e. warning because
IRQs are enabled). This also makes sense because __update_lru_size()
should not be updating any of the above stats.

folio_batch_move_lru() in the above call stack should be acquiring the
lock with IRQs disabled though, so I am not sure what's going on from
a quick look.

Adding Yu Zhao here.

Re: [syzbot] [cgroups?] [mm?] WARNING in __mod_memcg_lruvec_state

[Yu Zhao]

On Thu, Apr 4, 2024 at 7:36 PM Yosry Ahmed <yosryahmed@google.com> wrote:
>
> On Wed, Apr 3, 2024 at 6:08 PM Andrew Morton <akpm@linux-foundation.org> wrote:
> >
> > On Tue, 02 Apr 2024 01:03:26 -0700 syzbot <syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com> wrote:
> >
> > > Hello,
> > >
> > > syzbot found the following issue on:
> > >
> > > HEAD commit:    317c7bc0ef03 Merge tag 'mmc-v6.9-rc1' of git://git.kernel...
> > > git tree:       upstream
> > > console output: https://syzkaller.appspot.com/x/log.txt?x=15fd40c5180000
> > > kernel config:  https://syzkaller.appspot.com/x/.config?x=f64ec427e98bccd7
> > > dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
> > > compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> > >
> > > 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-317c7bc0.raw.xz
> > > vmlinux: https://storage.googleapis.com/syzbot-assets/efab473d72c0/vmlinux-317c7bc0.xz
> > > kernel image: https://storage.googleapis.com/syzbot-assets/5ba3f56d362d/bzImage-317c7bc0.xz
> > >
> > > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > > Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com
> > >
> > > ------------[ cut here ]------------
> > > WARNING: CPU: 0 PID: 30105 at mm/memcontrol.c:865 __mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
> > > Modules linked in:
> > > CPU: 0 PID: 30105 Comm: syz-executor.2 Not tainted 6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0
> > > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
> > > RIP: 0010:__mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
> > > Code: 45 85 e4 75 1d 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc b8 00 04 00 00 e9 80 fd ff ff 89 c6 e9 a0 fd ff ff 90 <0f> 0b 90 e9 a7 fc ff ff 48 c7 c7 18 43 e1 8f e8 32 51 f8 ff e9 5e
> > > RSP: 0018:ffffc900034beef8 EFLAGS: 00010202
> > > RAX: 0000000000000292 RBX: 0000000000000001 RCX: 1ffffffff1fc2863
> > > RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888024b92bc8
> > > RBP: ffff888024b92000 R08: 0000000000000005 R09: 0000000000000000
> > > R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
> > > R13: ffff88801c326000 R14: 0000000000000001 R15: ffff888024b92000
> > > FS:  00007f0811bf96c0(0000) GS:ffff88806b000000(0000) knlGS:0000000000000000
> > > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > > CR2: 000000000cfff1dd CR3: 000000003e4e2000 CR4: 0000000000350ef0
> > > DR0: 0000000000000031 DR1: 0000000000000000 DR2: 0000000000000000
> > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > > Call Trace:
> > >  <TASK>
> > >  __update_lru_size include/linux/mm_inline.h:47 [inline]
> > >  lru_gen_update_size include/linux/mm_inline.h:199 [inline]
> > >  lru_gen_add_folio+0x62d/0xe80 include/linux/mm_inline.h:262
> > >  lruvec_add_folio include/linux/mm_inline.h:323 [inline]
> > >  lru_add_fn+0x3fc/0xd80 mm/swap.c:215
> > >  folio_batch_move_lru+0x243/0x400 mm/swap.c:233
> >
> > Well it beats me.  I assume we failed to update for a new case.  I'll
> > toss this into -next to perhaps shed a bit of light.
> >
> > --- a/mm/memcontrol.c~__mod_memcg_lruvec_state-enhance-diagnostics
> > +++ a/mm/memcontrol.c
> > @@ -860,10 +860,12 @@ void __mod_memcg_lruvec_state(struct lru
> >                 case NR_ANON_THPS:
> >                 case NR_SHMEM_PMDMAPPED:
> >                 case NR_FILE_PMDMAPPED:
> > -                       WARN_ON_ONCE(!in_task());
> > +                       if (WARN_ON_ONCE(!in_task()))
> > +                               pr_warn("stat item index: %d\n", idx);
> >                         break;
> >                 default:
> > -                       VM_WARN_ON_IRQS_ENABLED();
> > +                       if (VM_WARN_ON_IRQS_ENABLED())
> > +                               pr_warn("stat item index: %d\n", idx);
>
> Line 865 from this commit should be this warning (i.e. warning because
> IRQs are enabled). This also makes sense because __update_lru_size()
> should not be updating any of the above stats.
>
> folio_batch_move_lru() in the above call stack should be acquiring the
> lock with IRQs disabled though, so I am not sure what's going on from
> a quick look.
>
> Adding Yu Zhao here.

Probably an RT build where _irqsave doesn't disable IRQ?

Re: [syzbot] [cgroups?] [mm?] WARNING in __mod_memcg_lruvec_state

[Yosry Ahmed]

On Thu, Apr 4, 2024 at 6:44 PM Yu Zhao <yuzhao@google.com> wrote:
>
> On Thu, Apr 4, 2024 at 7:36 PM Yosry Ahmed <yosryahmed@google.com> wrote:
> >
> > On Wed, Apr 3, 2024 at 6:08 PM Andrew Morton <akpm@linux-foundation.org> wrote:
> > >
> > > On Tue, 02 Apr 2024 01:03:26 -0700 syzbot <syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com> wrote:
> > >
> > > > Hello,
> > > >
> > > > syzbot found the following issue on:
> > > >
> > > > HEAD commit:    317c7bc0ef03 Merge tag 'mmc-v6.9-rc1' of git://git.kernel...
> > > > git tree:       upstream
> > > > console output: https://syzkaller.appspot.com/x/log.txt?x=15fd40c5180000
> > > > kernel config:  https://syzkaller.appspot.com/x/.config?x=f64ec427e98bccd7
> > > > dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
> > > > compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> > > >
> > > > 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-317c7bc0.raw.xz
> > > > vmlinux: https://storage.googleapis.com/syzbot-assets/efab473d72c0/vmlinux-317c7bc0.xz
> > > > kernel image: https://storage.googleapis.com/syzbot-assets/5ba3f56d362d/bzImage-317c7bc0.xz
> > > >
> > > > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > > > Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com
> > > >
> > > > ------------[ cut here ]------------
> > > > WARNING: CPU: 0 PID: 30105 at mm/memcontrol.c:865 __mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
> > > > Modules linked in:
> > > > CPU: 0 PID: 30105 Comm: syz-executor.2 Not tainted 6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0
> > > > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
> > > > RIP: 0010:__mod_memcg_lruvec_state+0x3fa/0x550 mm/memcontrol.c:865
> > > > Code: 45 85 e4 75 1d 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc b8 00 04 00 00 e9 80 fd ff ff 89 c6 e9 a0 fd ff ff 90 <0f> 0b 90 e9 a7 fc ff ff 48 c7 c7 18 43 e1 8f e8 32 51 f8 ff e9 5e
> > > > RSP: 0018:ffffc900034beef8 EFLAGS: 00010202
> > > > RAX: 0000000000000292 RBX: 0000000000000001 RCX: 1ffffffff1fc2863
> > > > RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888024b92bc8
> > > > RBP: ffff888024b92000 R08: 0000000000000005 R09: 0000000000000000
> > > > R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
> > > > R13: ffff88801c326000 R14: 0000000000000001 R15: ffff888024b92000
> > > > FS:  00007f0811bf96c0(0000) GS:ffff88806b000000(0000) knlGS:0000000000000000
> > > > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > > > CR2: 000000000cfff1dd CR3: 000000003e4e2000 CR4: 0000000000350ef0
> > > > DR0: 0000000000000031 DR1: 0000000000000000 DR2: 0000000000000000
> > > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > > > Call Trace:
> > > >  <TASK>
> > > >  __update_lru_size include/linux/mm_inline.h:47 [inline]
> > > >  lru_gen_update_size include/linux/mm_inline.h:199 [inline]
> > > >  lru_gen_add_folio+0x62d/0xe80 include/linux/mm_inline.h:262
> > > >  lruvec_add_folio include/linux/mm_inline.h:323 [inline]
> > > >  lru_add_fn+0x3fc/0xd80 mm/swap.c:215
> > > >  folio_batch_move_lru+0x243/0x400 mm/swap.c:233
> > >
> > > Well it beats me.  I assume we failed to update for a new case.  I'll
> > > toss this into -next to perhaps shed a bit of light.
> > >
> > > --- a/mm/memcontrol.c~__mod_memcg_lruvec_state-enhance-diagnostics
> > > +++ a/mm/memcontrol.c
> > > @@ -860,10 +860,12 @@ void __mod_memcg_lruvec_state(struct lru
> > >                 case NR_ANON_THPS:
> > >                 case NR_SHMEM_PMDMAPPED:
> > >                 case NR_FILE_PMDMAPPED:
> > > -                       WARN_ON_ONCE(!in_task());
> > > +                       if (WARN_ON_ONCE(!in_task()))
> > > +                               pr_warn("stat item index: %d\n", idx);
> > >                         break;
> > >                 default:
> > > -                       VM_WARN_ON_IRQS_ENABLED();
> > > +                       if (VM_WARN_ON_IRQS_ENABLED())
> > > +                               pr_warn("stat item index: %d\n", idx);
> >
> > Line 865 from this commit should be this warning (i.e. warning because
> > IRQs are enabled). This also makes sense because __update_lru_size()
> > should not be updating any of the above stats.
> >
> > folio_batch_move_lru() in the above call stack should be acquiring the
> > lock with IRQs disabled though, so I am not sure what's going on from
> > a quick look.
> >
> > Adding Yu Zhao here.
>
> Probably an RT build where _irqsave doesn't disable IRQ?

Yeah, that's possible. I don't have enough familiarity with RT to know
for sure. Perhaps lruvec->lru_lock needs to be changed to a
raw_spinlock_t? I am not sure if that's the correct course of action.

Re: [syzbot] [cgroups?] [mm?] WARNING in __mod_memcg_lruvec_state

[Shakeel Butt]

On Thu, Apr 04, 2024 at 09:47:34PM -0700, Yosry Ahmed wrote:
[...]
> >
> > Probably an RT build where _irqsave doesn't disable IRQ?
> 
> Yeah, that's possible. I don't have enough familiarity with RT to know
> for sure. Perhaps lruvec->lru_lock needs to be changed to a
> raw_spinlock_t? I am not sure if that's the correct course of action.

The kernel config does not have CONFIG_PREEMPT_RT enabled. However I
have not idea how irqs are getting enabled to raise this warning.

Re: [syzbot] [mm?] [cgroups?] WARNING in __mod_memcg_lruvec_state

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    2b84edefcad1 Add linux-next specific files for 20240506
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1164931f180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b499929e4aaba1af
dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=123d5d1f180000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16527450980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6a22cf95ee14/disk-2b84edef.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f5c45b515282/vmlinux-2b84edef.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9bf98258a662/bzImage-2b84edef.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com

------------[ cut here ]------------
__mod_memcg_lruvec_state: missing stat item 25
WARNING: CPU: 0 PID: 5091 at mm/memcontrol.c:999 __mod_memcg_lruvec_state+0x18c/0x430 mm/memcontrol.c:999
Modules linked in:
CPU: 0 PID: 5091 Comm: syz-executor374 Not tainted 6.9.0-rc7-next-20240506-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:__mod_memcg_lruvec_state+0x18c/0x430 mm/memcontrol.c:999
Code: ad 35 94 0d 00 0f 85 a4 01 00 00 c6 05 a0 35 94 0d 01 90 48 c7 c7 80 53 d7 8b 48 c7 c6 54 27 b8 8d 44 89 fa e8 55 f1 54 ff 90 <0f> 0b 90 90 e9 7c 01 00 00 4c 8d 7c 24 60 4c 89 fb 48 c1 eb 03 42
RSP: 0018:ffffc9000338f1e0 EFLAGS: 00010246
RAX: 38a0635190e19e00 RBX: ffffffff8fad3cb9 RCX: ffff8880221f0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000338f2c0 R08: ffffffff815846c2 R09: fffffbfff1c3995c
R10: dffffc0000000000 R11: fffffbfff1c3995c R12: 0000000000000200
R13: dffffc0000000000 R14: 1ffff92000671e40 R15: 0000000000000019
FS:  00005555900be380(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000061cca0 CR3: 0000000075f1c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __mod_lruvec_state mm/memcontrol.c:1055 [inline]
 __lruvec_stat_mod_folio+0x1a4/0x300 mm/memcontrol.c:1075
 __folio_add_file_rmap mm/rmap.c:1444 [inline]
 folio_add_file_rmap_pmd+0x29c/0x700 mm/rmap.c:1485
 do_set_pmd+0x767/0xc40 mm/memory.c:4650
 set_huge_pmd+0x28a/0x710 mm/khugepaged.c:1452
 collapse_pte_mapped_thp+0x5c7/0x10b0 mm/khugepaged.c:1655
 madvise_collapse+0x661/0xcc0 mm/khugepaged.c:2762
 madvise_vma_behavior mm/madvise.c:1094 [inline]
 madvise_walk_vmas mm/madvise.c:1268 [inline]
 do_madvise+0xc5f/0x44d0 mm/madvise.c:1464
 __do_sys_madvise mm/madvise.c:1481 [inline]
 __se_sys_madvise mm/madvise.c:1479 [inline]
 __x64_sys_madvise+0xa6/0xc0 mm/madvise.c:1479
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1421be72a9
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:00007fffb7f38b78 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007fffb7f38d58 RCX: 00007f1421be72a9
RDX: 0000000000000019 RSI: 0000000000800018 RDI: 0000000020000000
RBP: 00007f1421c5a610 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fffb7f38d48 R14: 0000000000000001 R15: 0000000000000001
 </TASK>


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

Re: [syzbot] [mm?] [cgroups?] WARNING in __mod_memcg_lruvec_state

[Yosry Ahmed]

On Mon, May 06, 2024 at 06:03:29AM -0700, syzbot wrote:
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    2b84edefcad1 Add linux-next specific files for 20240506
> git tree:       linux-next
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=1164931f180000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=b499929e4aaba1af
> dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=123d5d1f180000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16527450980000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/6a22cf95ee14/disk-2b84edef.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/f5c45b515282/vmlinux-2b84edef.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/9bf98258a662/bzImage-2b84edef.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com
> 
> ------------[ cut here ]------------
> __mod_memcg_lruvec_state: missing stat item 25
> WARNING: CPU: 0 PID: 5091 at mm/memcontrol.c:999 __mod_memcg_lruvec_state+0x18c/0x430 mm/memcontrol.c:999

This doesn't seem to be the same issue as the original one syzbot
reported. It's the same function but a different warning. I am not sure
how to tell syzbot that.

Anyway, this warning is the one newly introduced by Shakeel. It is
firing because NR_SHMEM_PMDMAPPED and/or NR_FILE_PMDMAPPED are being
updated using __lruvec_stat_mod_folio(), which also updates the memcg
stats. However, these stats are not exported per-memcg.

I think the following should fix it.

#syz test

diff --git a/mm/rmap.c b/mm/rmap.c
index 12be4241474ab..d3a26ea4dbae2 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1441,7 +1441,7 @@ static __always_inline void __folio_add_file_rmap(struct folio *folio,
 
 	nr = __folio_add_rmap(folio, page, nr_pages, level, &nr_pmdmapped);
 	if (nr_pmdmapped)
-		__lruvec_stat_mod_folio(folio, folio_test_swapbacked(folio) ?
+		__mod_node_page_state(folio, folio_test_swapbacked(folio) ?
 			NR_SHMEM_PMDMAPPED : NR_FILE_PMDMAPPED, nr_pmdmapped);
 	if (nr)
 		__lruvec_stat_mod_folio(folio, NR_FILE_MAPPED, nr);


> Modules linked in:
> CPU: 0 PID: 5091 Comm: syz-executor374 Not tainted 6.9.0-rc7-next-20240506-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
> RIP: 0010:__mod_memcg_lruvec_state+0x18c/0x430 mm/memcontrol.c:999
> Code: ad 35 94 0d 00 0f 85 a4 01 00 00 c6 05 a0 35 94 0d 01 90 48 c7 c7 80 53 d7 8b 48 c7 c6 54 27 b8 8d 44 89 fa e8 55 f1 54 ff 90 <0f> 0b 90 90 e9 7c 01 00 00 4c 8d 7c 24 60 4c 89 fb 48 c1 eb 03 42
> RSP: 0018:ffffc9000338f1e0 EFLAGS: 00010246
> RAX: 38a0635190e19e00 RBX: ffffffff8fad3cb9 RCX: ffff8880221f0000
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
> RBP: ffffc9000338f2c0 R08: ffffffff815846c2 R09: fffffbfff1c3995c
> R10: dffffc0000000000 R11: fffffbfff1c3995c R12: 0000000000000200
> R13: dffffc0000000000 R14: 1ffff92000671e40 R15: 0000000000000019
> FS:  00005555900be380(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 000000000061cca0 CR3: 0000000075f1c000 CR4: 00000000003506f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
>  <TASK>
>  __mod_lruvec_state mm/memcontrol.c:1055 [inline]
>  __lruvec_stat_mod_folio+0x1a4/0x300 mm/memcontrol.c:1075
>  __folio_add_file_rmap mm/rmap.c:1444 [inline]
>  folio_add_file_rmap_pmd+0x29c/0x700 mm/rmap.c:1485
>  do_set_pmd+0x767/0xc40 mm/memory.c:4650
>  set_huge_pmd+0x28a/0x710 mm/khugepaged.c:1452
>  collapse_pte_mapped_thp+0x5c7/0x10b0 mm/khugepaged.c:1655
>  madvise_collapse+0x661/0xcc0 mm/khugepaged.c:2762
>  madvise_vma_behavior mm/madvise.c:1094 [inline]
>  madvise_walk_vmas mm/madvise.c:1268 [inline]
>  do_madvise+0xc5f/0x44d0 mm/madvise.c:1464
>  __do_sys_madvise mm/madvise.c:1481 [inline]
>  __se_sys_madvise mm/madvise.c:1479 [inline]
>  __x64_sys_madvise+0xa6/0xc0 mm/madvise.c:1479
>  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>  do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f1421be72a9
> 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:00007fffb7f38b78 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
> RAX: ffffffffffffffda RBX: 00007fffb7f38d58 RCX: 00007f1421be72a9
> RDX: 0000000000000019 RSI: 0000000000800018 RDI: 0000000020000000
> RBP: 00007f1421c5a610 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
> R13: 00007fffb7f38d48 R14: 0000000000000001 R15: 0000000000000001
>  </TASK>
> 
> 
> ---
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.

Re: [syzbot] [mm?] [cgroups?] WARNING in __mod_memcg_lruvec_state

[Shakeel Butt]

On Mon, May 06, 2024 at 02:11:57PM +0000, Yosry Ahmed wrote:
> On Mon, May 06, 2024 at 06:03:29AM -0700, syzbot wrote:
> > syzbot has found a reproducer for the following issue on:
> > 
> > HEAD commit:    2b84edefcad1 Add linux-next specific files for 20240506
> > git tree:       linux-next
> > console+strace: https://syzkaller.appspot.com/x/log.txt?x=1164931f180000
> > kernel config:  https://syzkaller.appspot.com/x/.config?x=b499929e4aaba1af
> > dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
> > compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> > syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=123d5d1f180000
> > C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16527450980000
> > 
> > Downloadable assets:
> > disk image: https://storage.googleapis.com/syzbot-assets/6a22cf95ee14/disk-2b84edef.raw.xz
> > vmlinux: https://storage.googleapis.com/syzbot-assets/f5c45b515282/vmlinux-2b84edef.xz
> > kernel image: https://storage.googleapis.com/syzbot-assets/9bf98258a662/bzImage-2b84edef.xz
> > 
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com
> > 
> > ------------[ cut here ]------------
> > __mod_memcg_lruvec_state: missing stat item 25
> > WARNING: CPU: 0 PID: 5091 at mm/memcontrol.c:999 __mod_memcg_lruvec_state+0x18c/0x430 mm/memcontrol.c:999
> 
> This doesn't seem to be the same issue as the original one syzbot
> reported. It's the same function but a different warning. I am not sure
> how to tell syzbot that.
> 
> Anyway, this warning is the one newly introduced by Shakeel. It is
> firing because NR_SHMEM_PMDMAPPED and/or NR_FILE_PMDMAPPED are being
> updated using __lruvec_stat_mod_folio(), which also updates the memcg
> stats. However, these stats are not exported per-memcg.
> 
> I think the following should fix it.
> 

Hey Yosry, can you please post your patch with the signoff? The patch
looks good and you can put my ack on it.

> #syz test
> 
> diff --git a/mm/rmap.c b/mm/rmap.c
> index 12be4241474ab..d3a26ea4dbae2 100644
> --- a/mm/rmap.c
> +++ b/mm/rmap.c
> @@ -1441,7 +1441,7 @@ static __always_inline void __folio_add_file_rmap(struct folio *folio,
>  
>  	nr = __folio_add_rmap(folio, page, nr_pages, level, &nr_pmdmapped);
>  	if (nr_pmdmapped)
> -		__lruvec_stat_mod_folio(folio, folio_test_swapbacked(folio) ?
> +		__mod_node_page_state(folio, folio_test_swapbacked(folio) ?
>  			NR_SHMEM_PMDMAPPED : NR_FILE_PMDMAPPED, nr_pmdmapped);
>  	if (nr)
>  		__lruvec_stat_mod_folio(folio, NR_FILE_MAPPED, nr);
> 

Re: [syzbot] [mm?] [cgroups?] WARNING in __mod_memcg_lruvec_state

[Yosry Ahmed]

On Mon, May 6, 2024 at 8:59 AM Shakeel Butt <shakeel.butt@linux.dev> wrote:
>
> On Mon, May 06, 2024 at 02:11:57PM +0000, Yosry Ahmed wrote:
> > On Mon, May 06, 2024 at 06:03:29AM -0700, syzbot wrote:
> > > syzbot has found a reproducer for the following issue on:
> > >
> > > HEAD commit:    2b84edefcad1 Add linux-next specific files for 20240506
> > > git tree:       linux-next
> > > console+strace: https://syzkaller.appspot.com/x/log.txt?x=1164931f180000
> > > kernel config:  https://syzkaller.appspot.com/x/.config?x=b499929e4aaba1af
> > > dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
> > > compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> > > syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=123d5d1f180000
> > > C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16527450980000
> > >
> > > Downloadable assets:
> > > disk image: https://storage.googleapis.com/syzbot-assets/6a22cf95ee14/disk-2b84edef.raw.xz
> > > vmlinux: https://storage.googleapis.com/syzbot-assets/f5c45b515282/vmlinux-2b84edef.xz
> > > kernel image: https://storage.googleapis.com/syzbot-assets/9bf98258a662/bzImage-2b84edef.xz
> > >
> > > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > > Reported-by: syzbot+9319a4268a640e26b72b@syzkaller.appspotmail.com
> > >
> > > ------------[ cut here ]------------
> > > __mod_memcg_lruvec_state: missing stat item 25
> > > WARNING: CPU: 0 PID: 5091 at mm/memcontrol.c:999 __mod_memcg_lruvec_state+0x18c/0x430 mm/memcontrol.c:999
> >
> > This doesn't seem to be the same issue as the original one syzbot
> > reported. It's the same function but a different warning. I am not sure
> > how to tell syzbot that.
> >
> > Anyway, this warning is the one newly introduced by Shakeel. It is
> > firing because NR_SHMEM_PMDMAPPED and/or NR_FILE_PMDMAPPED are being
> > updated using __lruvec_stat_mod_folio(), which also updates the memcg
> > stats. However, these stats are not exported per-memcg.
> >
> > I think the following should fix it.
> >
>
> Hey Yosry, can you please post your patch with the signoff? The patch
> looks good and you can put my ack on it.

Will do. I noticed we also update these stats from
__folio_remove_rmap(). I will send a patch fixing these as well, so
I'll not include your Ack for that as it will be different.

Re: [syzbot] [mm?] [cgroups?] WARNING in __mod_memcg_lruvec_state

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

mm/rmap.c:1444:25: error: incompatible pointer types passing 'struct folio *' to parameter of type 'struct pglist_data *' [-Werror,-Wincompatible-pointer-types]


Tested on:

commit:         2b84edef Add linux-next specific files for 20240506
git tree:       linux-next
kernel config:  https://syzkaller.appspot.com/x/.config?x=b499929e4aaba1af
dashboard link: https://syzkaller.appspot.com/bug?extid=9319a4268a640e26b72b
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1655a590980000