From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <joro@8bytes.org>
Subject: Re: [PATCH] Use WARN_ON_ONCE for missing X86_FEATURE_NRIPS
Date: Mon, 5 Oct 2015 19:15:37 +0200
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Cc: Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org,
	Dirk =?iso-8859-1?Q?M=FCller?= <dmueller@suse.com>
To: Bandan Das <bsd@redhat.com>
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On Mon, Oct 05, 2015 at 12:54:43PM -0400, Bandan Das wrote:
> Joerg Roedel <joro@8bytes.org> writes:
> The problems is that the next_rip field could be stale. If the processor supports
> next_rip, then it will clear it out on the next entry. If it doesn't,
> an old value just sits there (no matter who wrote it) and the problem
> happens when skip_emulated_instruction advances the rip with an incorrect
> value.

So the right fix would be to just set the guests next_rip to 0 when we
emulate vmrun, just like real hardware does, no?


	Joerg