linux-kernel - Re: [PATCH 09/11] KVM: selftests: Drop manual XCR0 configuration from state test

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Message-ID: <87frpci689.fsf@redhat.com>
Date: Fri, 04 Oct 2024 11:10:14 +0200
From: Vitaly Kuznetsov <vkuznets@...hat.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini
 <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 09/11] KVM: selftests: Drop manual XCR0 configuration
 from state test

Sean Christopherson <seanjc@...gle.com> writes:

> Now that CR4.OSXSAVE and XCR0 are setup by default, drop the manual
> enabling from the state test, which is fully redundant with the default
> behavior.
>
> Signed-off-by: Sean Christopherson <seanjc@...gle.com>
> ---
>  tools/testing/selftests/kvm/x86_64/state_test.c | 5 -----
>  1 file changed, 5 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/x86_64/state_test.c b/tools/testing/selftests/kvm/x86_64/state_test.c
> index 1c756db329e5..141b7fc0c965 100644
> --- a/tools/testing/selftests/kvm/x86_64/state_test.c
> +++ b/tools/testing/selftests/kvm/x86_64/state_test.c
> @@ -145,11 +145,6 @@ static void __attribute__((__flatten__)) guest_code(void *arg)
>  
>  		memset(buffer, 0xcc, sizeof(buffer));
>  
> -		set_cr4(get_cr4() | X86_CR4_OSXSAVE);
> -		GUEST_ASSERT(this_cpu_has(X86_FEATURE_OSXSAVE));
> -
> -		xsetbv(0, xgetbv(0) | supported_xcr0);
> -
>  		/*
>  		 * Modify state for all supported xfeatures to take them out of
>  		 * their "init" state, i.e. to make them show up in XSTATE_BV.

Reviewed-by: Vitaly Kuznetsov <vkuznets@...hat.com>

-- 
Vitaly