Re: [Xen-devel] [PATCH v2 1/4] x86/mcheck: Minor cleanup to amd_nonfatal

[Tim Deegan <tim@xxxxxxx>]

At 12:22 +0100 on 16 Aug (1502886127), Andrew Cooper wrote:
>   * Drop trailing whitespace.
>   * Move amd_nonfatal_mcheck_init() into .init.text and drop a trailing 
> return.
>   * Drop unnecessary wmb()'s.  Because of Xen's implementation, they are only
>     compiler barriers anyway, and each wrmsr() is already fully serialising.

But wrmsr() is not a compiler barrier!  So if the write-barriers are
needed (e.g. for the update to the global 'adjust') then you can't
remove them just because WRMSR is a CPU barrier.

If they're not needed (which is plausible) then the commit message
should explain that instead.

Nit: I think tinkering with memory barriers deserves its own commit,
not to be the third item in a list of 'minor cleanup's.

Cheers,

Tim.

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