Re: [PATCH v6 10/18] sh/tlb: Convert SH to generic mmu_gather

From: Rich Felker
Date: Thu Dec 05 2019 - 14:25:43 EST


On Thu, Dec 05, 2019 at 01:24:02PM -0600, Rob Landley wrote:
> On 12/4/19 4:47 AM, Peter Zijlstra wrote:
> > On Tue, Dec 03, 2019 at 12:19:00PM +0100, Geert Uytterhoeven wrote:
> >> Hoi Peter,
> >>
> >> On Tue, Feb 19, 2019 at 11:35 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >>> Generic mmu_gather provides everything SH needs (range tracking and
> >>> cache coherency).
> >>>
> >>> Cc: Will Deacon <will.deacon@xxxxxxx>
> >>> Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx>
> >>> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> >>> Cc: Nick Piggin <npiggin@xxxxxxxxx>
> >>> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
> >>> Cc: Rich Felker <dalias@xxxxxxxx>
> >>> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> >>
> >> I got remote access to an SH7722-based Migo-R again, which spews a long
> >> sequence of BUGs during userspace startup. I've bisected this to commit
> >> c5b27a889da92f4a ("sh/tlb: Convert SH to generic mmu_gather").
> >
> > Whoopsy.. also, is this really the first time anybody booted an SH
> > kernel in over a year ?!?
>
> No, but most people running this kind of hardware tend not to upgrade to current
> kernels on a regular basis.
>
> The j-core guys tested the 5.3 release. I can't find an email about 5.4 so I
> dunno if that's been tested yet?

Being that this code is about mmu, does it affect nommu machines?
That's what we've got at present on the J-core side.

Rich