linux-kernel - Re: [PATCH 1/2] KVM: x86: Plumb in the vCPU to kvm_x86_ops.hwapic_isr

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <ZymYzawDv2wGA2c_@google.com>
Date: Mon, 4 Nov 2024 20:02:21 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Paolo Bonzini <pbonzini@...hat.com>, kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	"Markku Ahvenjärvi" <mankku@...il.com>, Janne Karhunen <janne.karhunen@...il.com>, 
	Chao Gao <chao.gao@...el.com>
Subject: Re: [PATCH 1/2] KVM: x86: Plumb in the vCPU to kvm_x86_ops.hwapic_isr_update()

On Fri, Nov 01, 2024, Sean Christopherson wrote:
> Pass the target vCPU to the hwapic_isr_update() vendor hook so that VMX
> can defer the update until after nested VM-Exit if an EOI for L1's vAPIC
> occurs while L2 is active.
> 
> No functional change intended.
> 
> Cc: stable@...r.kernel.org
> Signed-off-by: Sean Christopherson <seanjc@...gle.com>
> ---
>  arch/x86/include/asm/kvm_host.h |  2 +-
>  arch/x86/kvm/lapic.c            | 11 +++++------
>  arch/x86/kvm/vmx/vmx.c          |  2 +-
>  arch/x86/kvm/vmx/x86_ops.h      |  2 +-
>  4 files changed, 8 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index 70c7ed0ef184..3f3de047cbfd 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1734,7 +1734,7 @@ struct kvm_x86_ops {
>  	bool allow_apicv_in_x2apic_without_x2apic_virtualization;
>  	void (*refresh_apicv_exec_ctrl)(struct kvm_vcpu *vcpu);
>  	void (*hwapic_irr_update)(struct kvm_vcpu *vcpu, int max_irr);
> -	void (*hwapic_isr_update)(int isr);
> +	void (*hwapic_isr_update)(struct kvm_vcpu *vcpu, int isr);

Oh, the hilarity.  Got that one wrong.
 
  d39850f57d21 ("KVM: x86: Drop @vcpu parameter from kvm_x86_ops.hwapic_isr_update()")

Not entirely sure what cleanups were made possible by dropping @vcpu at the time.
I assume the end goal was ce0a58f4756c ("KVM: x86: Move "apicv_active" into "struct
kvm_lapic""), but that should have been possible, if slightly more annoying, without
modifying hwapic_isr_update().  *sigh*