lkml.org 
[lkml]   [2022]   [Mar]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 4.19 01/34] cgroup/cpuset: Fix a race between cpuset_attach() and cpu hotplug
    On Mon, Mar 14, 2022 at 12:19:41PM +0100, Michal Koutný wrote:
    > Hello.
    >
    > In my opinion there are two approaches:
    > a) drop this backport (given other races present),

    I have no problem with that, want to send a revert patch?

    > b) swap the locks compatible with v4.19 as this patch proposes.
    >
    > On Mon, Mar 14, 2022 at 05:11:50PM +0800, Zhang Qiao <zhangqiao22@huawei.com> wrote:
    > > + /*
    > > + * It should hold cpus lock because a cpu offline event can
    > > + * cause set_cpus_allowed_ptr() failed.
    > > + */
    > > + cpus_read_lock();
    >
    > Maybe just a nit, the old kernels before commit c5c63b9a6a2e ("cgroup:
    > Replace deprecated CPU-hotplug functions.") v5.15-rc1~159^2~5
    > would be more consistent with get_online_cpus() here (but they're
    > equivalent functionally so the locking order is correct).

    A fixed up patch would also be appreciated :)

    thanks,

    greg k-h

    \
     
     \ /
      Last update: 2022-09-17 16:17    [W:2.209 / U:0.208 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site