On Mon, 2020-02-24 at 11:29 -0500, Johannes Weiner wrote:
> On Sun, Feb 23, 2020 at 10:00:07PM -0500, Qian Cai wrote:
> > Similar to the commit d7495343228f ("cgroup: fix incorrect
> > WARN_ON_ONCE() in cgroup_setup_root()"), cgroup_id(root_cgrp) does not
> > equal to 1 on 32bit ino archs which triggers all sorts of issues with
> > psi_show() on s390x. For example,
> >
> > BUG: KASAN: slab-out-of-bounds in collect_percpu_times+0x2d0/
> > Read of size 4 at addr 000000001e0ce000 by task read_all/3667
> > collect_percpu_times+0x2d0/0x798
> > psi_show+0x7c/0x2a8
> > seq_read+0x2ac/0x830
> > vfs_read+0x92/0x150
> > ksys_read+0xe2/0x188
> > system_call+0xd8/0x2b4
> >
> > Fix it by using cgroup_ino().
> >
> > Fixes: 743210386c03 ("cgroup: use cgrp->kn->id as the cgroup ID")
> > Signed-off-by: Qian Cai <cai@xxxxxx>
>
> Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Tejun, can you take a look at this when you had a chance?
