Re: [PATCH 3/3 V2] pvclock: Get rid of __pvclock_read_cycles in function pvclock_read_flags

[Borislav Petkov]

On Thu, Jun 09, 2016 at 01:21:18PM +0200, Paolo Bonzini wrote:
> This is basically implementing a seqcount.  It needs two barriers and,

Why does it need the two barriers? More details please.

> technically, they should be virt_rmb() -- it really doesn't matter of
> course because reads are never reordered on x86.

You mean

	version = src->version;
	flags = src->flags;

are not reordered?

I don't think so.

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    Boris.

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