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From:   ebiederm@xmission.com (Eric W. Biederman)
To:     "Maciej W. Rozycki" <macro@orcam.me.uk>
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
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Date:   Mon, 25 Oct 2021 15:55:13 -0500
In-Reply-To: <alpine.DEB.2.21.2110240622100.45807@angie.orcam.me.uk> (Maciej
        W. Rozycki's message of "Sun, 24 Oct 2021 06:24:17 +0200 (CEST)")
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Subject: Re: [PATCH 05/20] signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT
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"Maciej W. Rozycki" <macro@orcam.me.uk> writes:

> 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>
>

I will add a CC stable.  So it can be backported after it is merged.

Eric