Re: Fwd: Memory corruption in multithreaded user space program while calling fork

From: Andrew Morton
Date: Tue Jul 04 2023 - 12:18:15 EST


On Tue, 4 Jul 2023 09:00:19 +0100 Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:

> > > > > Thanks! I'll investigate this later today. After discussing with
> > > > > Andrew, we would like to disable CONFIG_PER_VMA_LOCK by default until
> > > > > the issue is fixed. I'll post a patch shortly.
> > > >
> > > > Posted at: https://lore.kernel.org/all/20230703182150.2193578-1-surenb@xxxxxxxxxx/
> > >
> > > As that change fixes something in 6.4, why not cc: stable on it as well?
> >
> > Sorry, I thought since per-VMA locks were introduced in 6.4 and this
> > patch is fixing 6.4 I didn't need to send it to stable for older
> > versions. Did I miss something?
>
> 6.4.y is a stable kernel tree right now, so yes, it needs to be included
> there :)

I'm in wait-a-few-days-mode on this. To see if we have a backportable
fix rather than disabling the feature in -stable.