On Mon, May 6, 2024 at 8:59 AM Shakeel Butt <shakeel.butt@xxxxxxxxx> 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@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > > > ------------[ 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.
