Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Michael Ellerman <mpe@ellerman.id.au>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>
Cc:     linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] powerpc/32s: Fix RTAS machine check with VMAP stack
In-Reply-To: <6ed0b74d-8d01-4a20-faed-891496fb77b4@csgroup.eu>
References: <bc77d61d1c18940e456a2dee464f1e2eda65a3f0.1608621048.git.christophe.leroy@csgroup.eu> <6ed0b74d-8d01-4a20-faed-891496fb77b4@csgroup.eu>
Date:   Thu, 24 Dec 2020 12:05:43 +1100
Message-ID: <87im8s6mjc.fsf@mpe.ellerman.id.au>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

Christophe Leroy <christophe.leroy@csgroup.eu> writes:
> Le 22/12/2020 =C3=A0 08:11, Christophe Leroy a =C3=A9crit=C2=A0:
>> When we have VMAP stack, exception prolog 1 sets r1, not r11.
>
> But exception prolog 1 uses r1 to setup r1 when machine check happens in =
kernel.
> So r1 must be restored when the branch is not taken. See subsequent patch=
 I just sent out.

OK. This is still on the tip of fixes, so I'll rewind it to drop this
commit, and then apply this and the fixup as one patch next week.

cheers