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;
Date:   Sun, 24 Oct 2021 06:24:17 +0200 (CEST)
From:   "Maciej W. Rozycki" <macro@orcam.me.uk>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
cc:     linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>,
        Al Viro <viro@ZenIV.linux.org.uk>,
        Kees Cook <keescook@chromium.org>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        linux-mips@vger.kernel.org
Subject: Re: [PATCH 05/20] signal/mips: Update (_save|_restore)_fp_context
 to fail with -EFAULT
In-Reply-To: <20211020174406.17889-5-ebiederm@xmission.com>
Message-ID: <alpine.DEB.2.21.2110240622100.45807@angie.orcam.me.uk>
References: <87y26nmwkb.fsf@disp2133> <20211020174406.17889-5-ebiederm@xmission.com>
User-Agent: Alpine 2.21 (DEB 202 2017-01-01)
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Precedence: bulk

On Wed, 20 Oct 2021, Eric W. Biederman wrote:

> When an instruction to save or restore a register from the stack fails
> in _save_fp_context or _restore_fp_context return with -EFAULT.  This
> change was made to r2300_fpu.S[1] but it looks like it got lost with
> the introduction of EX2[2].  This is also what the other implementation
> of _save_fp_context and _restore_fp_context in r4k_fpu.S does, and
> what is needed for the callers to be able to handle the error.

 Umm, right, good catch, thanks!  I think this ought to be backported.

Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>

  Maciej