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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 20 Apr 2020 13:27:36 -0700
Message-ID: <CAHk-=whNL-P71xQRsahpYrzKquvz3WwqPCUVPT+1TUmWZ+67TQ@mail.gmail.com>
Subject: Re: [PATCH] x86/memcpy: Introduce memcpy_mcsafe_fast
To:     "Luck, Tony" <tony.luck@intel.com>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        Andy Lutomirski <luto@amacapital.net>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, X86 ML <x86@kernel.org>,
        stable <stable@vger.kernel.org>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Erwin Tsaur <erwin.tsaur@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-nvdimm <linux-nvdimm@lists.01.org>
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On Mon, Apr 20, 2020 at 1:23 PM Luck, Tony <tony.luck@intel.com> wrote:
>
> I think they do. If the result of the wrong data has already
> been sent out the network before you process the signal, then you
> will need far smarter application software than has ever been written
> to hunt it down and stop the spread of the bogus result.

Bah. That's a completely red herring argument.

By "asynchronous" I don't mean "hours later".

Make it be "interrupts are enabled, before serializing instruction".

Yes, we want bounded error handling latency. But that doesn't mean "synchronous"

           Linus