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Subject: Re: [PATCH] KVM: x86: Fix the NULL pointer parameter in
 check_cr_write()
To: Yu Zhang <yu.c.zhang@linux.intel.com>,
        Jim Mattson <jmattson@google.com>,
        David Hildenbrand <david@redhat.com>
Cc: kvm list <kvm@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H . Peter Anvin" <hpa@zytor.com>
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 <0a2a586b-5dd6-88cb-bd22-f0676b1c8fbe@linux.intel.com>
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <0f652327-03f4-5fba-0717-d1f29e45d6cf@redhat.com>
Date: Wed, 20 Sep 2017 10:13:54 +0200
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On 20/09/2017 08:35, Yu Zhang wrote:
> 
> 2 reasons I did not choose to change kvm_cpuid(): 1> like Jim's
> comments, kvm_cpuid() will eventually write the *eax - *edx no
> matter a cpuid entry is found or not; 2> currently, return value of
> kvm_cpuid() is either true when an entry is found or false otherwise.
> We can change kvm_cpuid() to check the pointers of GPRs against NULL
> and return false immediately. Then the false value would have 2
> different meanings - entry not found, or invalid params.
> 
> Paolo, any suggestion? :-)

Radim, has already sent this version to Linus. :)

Paolo