Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy()

From	Tony Luck <tony.luck@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy()
Date	2016-01-14 00:30 +0100
Message-ID	<qQD1v-6Mu-1@gated-at.bofh.it> (permalink)
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On Mon, Jan 11, 2016 at 2:44 AM, Ingo Molnar <mingo@kernel.org> wrote:
> So such a synthetic CPUID bit would definitely be useful.
>
> Also, knowing whether a memcpy function is recoverable or not, should not be
> delegated to callers: there should be the regular memcpy APIs, plus new APIs that
> do everything they can to provide recoverable memory copies. Whether it's achieved
> via flag checking, a function pointer or code patching is an implementation detail
> that's not visible to drivers making use of the new facility.
>
> I'd go for the simplest, most robust solution initially, also perhaps with boot
> time messages to make sure users know which variant is used and now.

Are there some examples of synthetic CPUID bits?  I grepped around and
found a handful of places making ad hoc decisions based on sub-strings of
x86_model_id[] ... but didn't find any systematic approach.

-Tony

Thread

[PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Tony Luck <tony.luck@intel.com> - 2016-01-09 01:20 +0100
  Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Andy Lutomirski <luto@amacapital.net> - 2016-01-09 02:50 +0100
    Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Tony Luck <tony.luck@gmail.com> - 2016-01-09 18:50 +0100
      Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Andy Lutomirski <luto@amacapital.net> - 2016-01-09 19:00 +0100
        Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Tony Luck <tony.luck@gmail.com> - 2016-01-09 20:50 +0100
          Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Dan Williams <dan.j.williams@intel.com> - 2016-01-09 23:20 +0100
            Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Andy Lutomirski <luto@amacapital.net> - 2016-01-09 23:40 +0100
              Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Dan Williams <dan.j.williams@intel.com> - 2016-01-10 01:30 +0100
                Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Tony Luck <tony.luck@gmail.com> - 2016-01-10 02:50 +0100
                Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Borislav Petkov <bp@alien8.de> - 2016-01-10 12:30 +0100
                Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Ingo Molnar <mingo@kernel.org> - 2016-01-11 11:50 +0100
                Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Tony Luck <tony.luck@gmail.com> - 2016-01-14 00:30 +0100
                Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Borislav Petkov <bp@alien8.de> - 2016-01-14 05:50 +0100
    Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() "Luck, Tony" <tony.luck@intel.com> - 2016-01-12 01:30 +0100
      Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Andy Lutomirski <luto@amacapital.net> - 2016-01-12 01:40 +0100
      Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy() Andy Lutomirski <luto@amacapital.net> - 2016-01-12 01:40 +0100

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