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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Dan Williams <dan.j.williams@intel.com>
Cc:     Borislav Petkov <bp@alien8.de>,
        LKML <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        Sean Christopherson <seanjc@google.com>,
        Dave Hansen <dave.hansen@linux.intel.com>
Subject: Re: [patch 01/10] x86/fpu/signal: Clarify exception handling in
 restore_fpregs_from_user()
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Date:   Wed, 01 Sep 2021 17:52:25 +0200
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On Wed, Sep 01 2021 at 14:00, Thomas Gleixner wrote:
>
> commit b2f9d678e28c ("x86/mce: Check for faults tagged in
> EXTABLE_CLASS_FAULT exception table entries") made use of this in MCE to
> allow in kernel recovery. The only thing it uses is checking the
> exception handler type.
>
> Bah. I'll fix that up to make that less obscure.
>
> The remaining two use cases (SGX and FPU) make use of the stored trap
> number.

Though while for the FPU use case we really want to handle the #MC case,
it's not clear to me whether this is actually correct for SGX.

Jarkko, Sean, Dave?

Thanks,

        tglx