From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH -v2] kvm: Emulate MOVBE
Date: Tue, 16 Apr 2013 13:36:00 +0200
Message-ID: <516D37A0.2070706@redhat.com>
References: <20130409234602.GI5077@pd.tnic> <20130410112942.07dfc167@slackpad> <20130410100845.GB17919@redhat.com> <20130410123901.46b65169@slackpad> <20130410121639.GE17919@redhat.com> <20130411001815.GA17544@pd.tnic> <20130414084303.GE17919@redhat.com> <20130414210218.GF20547@pd.tnic>
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Cc: Gleb Natapov <gleb@redhat.com>, Andre Przywara <andre@andrep.de>,
	kvm@vger.kernel.org,
	=?UTF-8?B?SsO2cmcgUsO2ZGVs?= <joro@8bytes.org>,
	"H. Peter Anvin" <hpa@zytor.com>, x86-ml <x86@kernel.org>
To: Borislav Petkov <bp@alien8.de>
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Il 14/04/2013 23:02, Borislav Petkov ha scritto:
> 	*(u16 *)&ctxt->dst.val = swab16((u16)ctxt->src.val);
> 
> 	movzwl  112(%rdi), %eax # ctxt_5(D)->src.D.27823.val, tmp82
> 	rolw    $8, %ax #, tmp82
> 	movw    %ax, 240(%rdi)  # tmp82, MEM[(u16 *)ctxt_5(D) + 240B]

I think this breaks the C aliasing rules.

Using valptr is okay because it is a char.

Paolo