Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr

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From	Andi Kleen <andi@firstfloor.org>
Newsgroups	linux.kernel
Subject	Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr
Date	Mon, 20 Jun 2016 23:20:02 +0200
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Borislav Petkov <bp@alien8.de> writes:

> Comments are, as always, appreciated.

Seems like a waste of kernel code to me. The MSR interface works
perfectly fine. There are potentially hundreds of useful MSRs,
are you going to add new sysfs for each of them?

Even the more obscure ones can be very useful for debugging
and monitoring.

Most MSRs are model specific so this would end up with tons
of switch (x86_model) ... which are always difficult to maintain
and need to be updated all the time when new CPUs come out.

This will likely generate a really large ongoing number of patches,
and to solve what problem exactly?

The whole thing doesn't make any sense to me.

It's just a waste of code, maintainer time, patch review
capacity, which all could be far more usefully employed
to do something that actually solves real problems.

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only

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[RFC PATCH] x86: Move away from /dev/cpu/*/msr Borislav Petkov <bp@alien8.de> - 2016-06-15 12:10 +0200
  Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr chenyu <yu.chen.surf@gmail.com> - 2016-06-15 12:30 +0200
    Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Borislav Petkov <bp@alien8.de> - 2016-06-15 12:40 +0200
      Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Borislav Petkov <bp@alien8.de> - 2016-06-15 16:10 +0200
  Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Len Brown <lenb@kernel.org> - 2016-06-15 18:50 +0200
    Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Borislav Petkov <bp@alien8.de> - 2016-06-15 19:00 +0200
      Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Len Brown <lenb@kernel.org> - 2016-06-15 19:30 +0200
        Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Borislav Petkov <bp@alien8.de> - 2016-06-15 19:40 +0200
          Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Len Brown <lenb@kernel.org> - 2016-06-15 19:50 +0200
            Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Borislav Petkov <bp@alien8.de> - 2016-06-15 20:00 +0200
  Re: [RFC PATCH] x86: Move away from /dev/cpu/*/msr Andi Kleen <andi@firstfloor.org> - 2016-06-20 23:20 +0200

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