From nobody Fri Dec 19 15:47:54 2025 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6CFFE2DC784; Thu, 6 Nov 2025 10:09:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762423773; cv=none; b=aDcT/p6/bGIAllr48HLh4CpJc8gd56DzDK82/aU4YDGneJJAI/3K1475uUCVD32YYr+3AMTrM72w2AHjU9Uk5+5Cy4H2LGgZ7IlQTVeCh3uVnmbDKXRRQFiLhJ+XJRGUiUJ4HH4FbTbJFmbC5dz751IecFrMUmG7+t/upU3RL08= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762423773; c=relaxed/simple; bh=H2SNqHuTgmxJrrhJpWRRVpG1pyyTjyevFP2IE6kgncA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ryD986ev+lu0ENjD65b7M+SwTKh4FBJjIuWG3CkpM/yuFiIuIlAPAPmwkZh3nVCAkp8kpOtX8sWh5hgHzqpAsiIObzHTVyepmNRJEktv1ctHTkIHkIW5AxCd031c+TWdpXv5D7U65RnvE0ekqGE+gBH0Ecipiz2eMdcAIK3eo3I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=eYLUK4eS; arc=none smtp.client-ip=192.198.163.8 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="eYLUK4eS" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1762423772; x=1793959772; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=H2SNqHuTgmxJrrhJpWRRVpG1pyyTjyevFP2IE6kgncA=; b=eYLUK4eSgHeVqWOkO5e5pHHScqzA0MN6dlqWEgbHZ3eahEbZy05aDEGJ ALZeAKyV1gecPpQgqWeY/Aaie1tEZdiB6EWyO9EMS+v2F0aSJQXozh6iT TMdP24kM58l7LpVr/XHZgEXcNOYk6z4VLOHeyACaaXTxvHkyGHbiQmrSH +JW9Zrp9o6/9mvRbBFvZt4Nm3cXS6Wda+nUHt+qtb12uCl+/3ICkQtYbk iD/7ly7yq8kVrONj7emAV1FG0fjNZ8yzD+HgdD+WupJLtoBJeJUVq/lab zABmnkh3uHLaitcGUtO9VYyyP5gyqd85u2BmZQbjaYfgEyF6XPPEAcpJZ A==; X-CSE-ConnectionGUID: whegdeHnQvydarxGyN6dRA== X-CSE-MsgGUID: wu69TjalTq26ycKNJ83qyA== X-IronPort-AV: E=McAfee;i="6800,10657,11604"; a="82186406" X-IronPort-AV: E=Sophos;i="6.19,284,1754982000"; d="scan'208";a="82186406" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Nov 2025 02:09:31 -0800 X-CSE-ConnectionGUID: M/kPqBTQQMG8Vgsma1BV+w== X-CSE-MsgGUID: kR4W3VKWQuu4D6YPpvMx4A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,284,1754982000"; d="scan'208";a="187007555" Received: from litbin-desktop.sh.intel.com ([10.239.159.60]) by orviesa010-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Nov 2025 02:09:29 -0800 From: Binbin Wu To: seanjc@google.com, pbonzini@redhat.com Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, binbin.wu@linux.intel.com Subject: [PATCH] KVM: x86: Add a help to dedup loading guest/host XCR0 and XSS Date: Thu, 6 Nov 2025 18:11:38 +0800 Message-ID: <20251106101138.2756175-1-binbin.wu@linux.intel.com> X-Mailer: git-send-email 2.46.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add and use a helper, kvm_load_xfeatures(), to dedup the code that loads guest/host xfeatures by passing XCR0 and XSS values accordingly. No functional change intended. Signed-off-by: Binbin Wu Reviewed-by: Chao Gao --- The patch is based on the patch series "KVM: x86: Cleanup #MC and XCR0/XSS/PKRU handling" [1], which is applied on=20 top of kvm-x86 next branch(commit a996dd2a5e1ec54dcf7d7b93915ea3f97e14e68a). [1] https://lore.kernel.org/all/20251030224246.3456492-1-seanjc@google.com --- arch/x86/kvm/x86.c | 25 +++++-------------------- 1 file changed, 5 insertions(+), 20 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b8df02a083b2..35fc1333e198 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1203,33 +1203,18 @@ void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long = msw) } EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_lmsw); =20 -static void kvm_load_guest_xfeatures(struct kvm_vcpu *vcpu) +static void kvm_load_xfeatures(struct kvm_vcpu *vcpu, u64 xcr0, u64 xss) { if (vcpu->arch.guest_state_protected) return; =20 if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) { if (vcpu->arch.xcr0 !=3D kvm_host.xcr0) - xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0); + xsetbv(XCR_XFEATURE_ENABLED_MASK, xcr0); =20 if (guest_cpu_cap_has(vcpu, X86_FEATURE_XSAVES) && vcpu->arch.ia32_xss !=3D kvm_host.xss) - wrmsrq(MSR_IA32_XSS, vcpu->arch.ia32_xss); - } -} - -static void kvm_load_host_xfeatures(struct kvm_vcpu *vcpu) -{ - if (vcpu->arch.guest_state_protected) - return; - - if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) { - if (vcpu->arch.xcr0 !=3D kvm_host.xcr0) - xsetbv(XCR_XFEATURE_ENABLED_MASK, kvm_host.xcr0); - - if (guest_cpu_cap_has(vcpu, X86_FEATURE_XSAVES) && - vcpu->arch.ia32_xss !=3D kvm_host.xss) - wrmsrq(MSR_IA32_XSS, kvm_host.xss); + wrmsrq(MSR_IA32_XSS, xss); } } =20 @@ -11310,7 +11295,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) if (vcpu->arch.guest_fpu.xfd_err) wrmsrq(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err); =20 - kvm_load_guest_xfeatures(vcpu); + kvm_load_xfeatures(vcpu, vcpu->arch.xcr0, vcpu->arch.ia32_xss); =20 if (unlikely(vcpu->arch.switch_db_regs && !(vcpu->arch.switch_db_regs & KVM_DEBUGREG_AUTO_SWITCH))) { @@ -11406,7 +11391,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) vcpu->mode =3D OUTSIDE_GUEST_MODE; smp_wmb(); =20 - kvm_load_host_xfeatures(vcpu); + kvm_load_xfeatures(vcpu, kvm_host.xcr0, kvm_host.xss); =20 /* * Sync xfd before calling handle_exit_irqoff() which may base-commit: a996dd2a5e1ec54dcf7d7b93915ea3f97e14e68a prerequisite-patch-id: 9aafd634f0ab2033d7b032e227d356777469e046 prerequisite-patch-id: 656ce1f5aa97c77a9cf6125713707a5007b2c7ba prerequisite-patch-id: d6328b8c0fdb8593bb534ab7378821edcf9f639d prerequisite-patch-id: c7f36d1cedc4ae6416223d2225460944629b3d4f --=20 2.46.0