From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <joro@8bytes.org>
Subject: Re: [PATCH 05/13] KVM: SVM: Add intercept check for emulated cr
	accesses
Date: Sat, 26 Mar 2011 12:06:18 +0100
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Cc: Joerg Roedel <joerg.roedel@amd.com>,
	Marcelo Tosatti <mtosatti@redhat.com>, kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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On Sat, Mar 26, 2011 at 11:37:42AM +0200, Avi Kivity wrote:
> On 03/25/2011 11:29 AM, Joerg Roedel wrote:
>> This patch adds all necessary intercept checks for
>> instructions that access the crX registers.
>>
>>
>> @@ -3871,11 +3871,89 @@ static void svm_fpu_deactivate(struct kvm_vcpu *vcpu)
>>   	update_cr0_intercept(svm);
>>   }
>>
>> +#define POST_EX(exit) { .exit_code = (exit), \
>> +			.stage = x86_icpt_post_except, \
>> +			.valid = true }
>> +
>> +static struct __x86_intercept {
>> +	u32 exit_code;
>> +	enum x86_intercept_stage stage;
>> +	bool valid;
>
> Isn't .valid always true, even in later patches?

The rational here was that the arrary below may not be fully populated
in the future and the svm_check_intercept function needs a way to find
out if it retrieved a populated value. Checks for zero values don't work
because exit_code and stage could both be zero and valid. So I added an
extra field to check that.
I''ll fix the other things you pointed out in the next version.

Regards,

	Joerg