From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH uq/master] kvm: always update the MPX model specific register
Date: Wed, 22 Jan 2014 17:35:31 +0100
Message-ID: <52DFF353.1060307@redhat.com>
References: <1390224336-27009-1-git-send-email-pbonzini@redhat.com> <20140122152917.GA22855@amt.cnet>
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Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org,
	Liu Jinsong <jinsong.liu@intel.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
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Il 22/01/2014 16:29, Marcelo Tosatti ha scritto:
> > The original patch from Liu Jinsong restricted them to reset or full
> > state updates, but that's unnecessary (and wrong) since the BNDCFGS
> > MSR has no side effects.
>
> Why is it necessary to save/restore BNDCFGS MSR on states other
> than FULL and RESET?

Yes, nothing in QEMU except reset will touch the MSR, but this applies 
also to all the other MSRs that are saved unconditionally.  It's nice to 
be able to poke them with gdb, and saving/restoring the MSR provides that.

Paolo