stable: KASan for ARM

[Ard Biesheuvel]

(+ Russell)

On Sun, 7 Mar 2021 at 16:21, Greg Kroah-Hartman
<gregkh at linuxfoundation.org> wrote:
>
> On Sun, Mar 07, 2021 at 04:00:40PM +0100, Michał Mirosław wrote:
> > Dear Greg,
> >
> > Would you consider KASan for ARM patches for LTS (5.10) kernel? Those
> > are 7a1be318f579..421015713b30 if I understand correctly. They are
> > not normal stable material, but I think they will help tremendously in
> > discovering kernel bugs on 32-bit ARMs.
>
> Looks like a new feature to me, right?
>
> How many patches, and have you tested them?  If so, submit them as a
> patch series and we can review them, but if this is a new feature, it
> does not meet the stable kernel rules.
>
> And why not just use 5.11 or newer for discovering kernel bugs?  Why
> does 5.10 matter here?
>

The KASan support was rather tricky to get right, so I don't think
this is suitable for stable. The range 7a1be318f579..421015713b30 is
definitely not complete (we'd need at least
e9a2f8b599d0bc22a1b13e69527246ac39c697b4 and
10fce53c0ef8f6e79115c3d9e0d7ea1338c3fa37 as well), and the intrusive
nature of those changes means they are definitely not appropriate as
stable backports.

-- 
Ard.