From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH 5/6] KVM: x86: Wrong assertion on paging_tmpl.h
Date: Wed, 08 Oct 2014 11:17:20 +0200
Message-ID: <54350120.8070204@redhat.com>
References: <1412099359-5316-1-git-send-email-namit@cs.technion.ac.il> <1412099359-5316-6-git-send-email-namit@cs.technion.ac.il> <20141001162603.GE12085@potion.brq.redhat.com> <DF6289B1-6450-4FC5-ACB3-9F4F7F7D6751@gmail.com>
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Cc: Nadav Amit <namit@cs.technion.ac.il>, kvm@vger.kernel.org
To: Nadav Amit <nadav.amit@gmail.com>,
	=?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>
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Il 01/10/2014 19:14, Nadav Amit ha scritto:
>>>>> +	ASSERT(!is_long_mode(vcpu) || is_pae(vcpu));
> I am ok with removing the assertion. Due to the multiple changes, I
> lost track what it was supposed to do. Anyhow, removing the second
> part was required since there are no reserved bits in non-pae (they
> are ignored - not reserved).

It becomes a bit clearer if you apply De Morgan:

        ASSERT(!(is_long_mode(vcpu) && !is_pae(vcpu)));

or almost equivalently

        WARN_ON(is_long_mode(vcpu) && !is_pae(vcpu));

We should change ASSERT to positive logic (MMU_WARN_ON for example).

Paolo
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