linux-kernel - Re: [PATCH 2/4] kvm, vmx: move register clearing out of assembly path

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Message-ID: <1540549886.30273.54.camel@amazon.de>
Date:   Fri, 26 Oct 2018 10:31:26 +0000
From:   "Stecklina, Julian" <jsteckli@...zon.de>
To:     "jmattson@...gle.com" <jmattson@...gle.com>
CC:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "kvm@...r.kernel.org" <kvm@...r.kernel.org>,
        "js@...en8.de" <js@...en8.de>,
        "pbonzini@...hat.com" <pbonzini@...hat.com>
Subject: Re: [PATCH 2/4] kvm, vmx: move register clearing out of assembly path

On Thu, 2018-10-25 at 09:55 -0700, Jim Mattson wrote:
> Looking at the second asm statement and the comment that precedes it,
> my first question would be, "What about the registers not covered
> here?"

Good point. I'll make the comment a bit clearer.

>  I'm also not convinced that the register-clearing asm statement
> is actually "clearer" with some registers cleared as input arguments
> and others cleared explicitly, but otherwise, the change looks fine
> to
> me.

The inline assembly itself may not be clearer, but it has a single
purpose now. You are free to ignore it if you want to change aspects of
the VM entry path. It almost fits on a single screen now. ;)

> 
> Reviewed-by: Jim Mattson <jmattson@...gle.com>

Thanks!
Julian
Amazon Development Center Germany GmbH
Berlin - Dresden - Aachen
main office: Krausenstr. 38, 10117 Berlin
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