From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f74.google.com (mail-pj1-f74.google.com [209.85.216.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9753025291B for ; Mon, 13 Oct 2025 17:49:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760377763; cv=none; b=C8IVSrrr7g4vvuYOcBChIZkkv5MFt3FdxW/eUSOdQ3mz4w29pWPyN6CgMDQDb4v+UD8Fg0mE3nXTWHFiBS6yJAR+hWk83CqJ/NMCxPJUKfg4MXJkLpnl8FlQW/bHlwFgaON9T0qXsRRxbh08MNdlVjFmQQEJNOtGFYfc9gGzDWY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760377763; c=relaxed/simple; bh=YpOrvarDsgX+BoUcJp30a+73+gS1d+gCoNWkzrol2Qg=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=DYr9/krVIvx4nsgo3Jlq4I5KhhaHW+AO3dyoHnbXN177LM7Q93b+L9g423ePNu/xO7czW4zuQEv9U547eOhrnYLrdSNcwcJwRdgIPsaE7E6+Rwb99S9/ytZUDq2nGppt/5ICX2gAsoTstmCCHPT0lc0k0q5LYfof9Ou4VcIbh/E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=aYDoKku+; arc=none smtp.client-ip=209.85.216.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="aYDoKku+" Received: by mail-pj1-f74.google.com with SMTP id 98e67ed59e1d1-339ee7532b9so23770533a91.3 for ; Mon, 13 Oct 2025 10:49:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1760377761; x=1760982561; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=LukZPy5/CZdWHCV/h7XbMjLCjzkVUD5w5QgJZZyHQqI=; b=aYDoKku+jZmKnk4if5dd0rTv1LX6iyEHKcnXuhcklX0LO3cjxUAHj2zZtyNHt6FECE BxSWWTK525BaO8xEefXbJBsKIfytOgSgbDrpNbJNYewtaKuJW5/lEY+RYHQzBmsknE6T LoLerJ/sAMKCpppWLtEJ78nVmgy6t6LkJGox8mYmlhN+6y7bbsFxdIIPr4HO3TJZUvyV 0VLfoEBBpFrflboIxp/xioT1BSfEhLUsJdSQ+hkUOeP5ItaKuI7GJXh6Tr2VS9kPPyj1 MmjpbIG+0ZxIuwSscsw63MQyfcg1Ps/QF4cocMjazgH8x/d4ylthOtNcF43Jr/bjk+5Q 2T1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1760377761; x=1760982561; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=LukZPy5/CZdWHCV/h7XbMjLCjzkVUD5w5QgJZZyHQqI=; b=IHki4AVa4MlE3Wv4OXIT5dsMy8lWaY9T8Mo3ZOidfy8hGAqQRs4G1uPvQ+/iovgoVG naUG4EK3ZKBFkJLZw3mQwizz5ENthejZi0OHSLw8O9a5zBHnPXlgr6pKIYUFEyHc/IRU UUE+73ksMoI7cBZwkm4QChQkllKM32zpVc/oGapkKRgOhfGyvHYRgC2oAG8PQhUjH4KZ UZCrONI80DpcHWHg8xYiJaCQiCiLlID5tRrVHQXiJDNi0zIfNwwN8ppdIymihBN1Bavd ngNSpssb/lBoCLOLURZsBbOY9HNFclrbC6Ch/e8FJcR7pzohYd7RxfNfrunwqcwXMWji ZgBQ== X-Forwarded-Encrypted: i=1; AJvYcCUnYlMhzAhX0kWIHrMu5IxRMPQWPLKzhDd9SAAWOSGkGNCSe11nCmPMFM1A5PWI5UkU6X4edPVWMI99kPY=@vger.kernel.org X-Gm-Message-State: AOJu0Yx1HLfmvz2H3MyRLz2vO0rUWyDIXypshTKl9NsIViv6yfQNcaHC Z94bYHMrvAr+hopjWH8L/6BECI94uCb/gDMvLdeDH6pNTnGMtT4CB5vWf/mX2GACoeiXFoWJ/uZ 8ldXiNA== X-Google-Smtp-Source: AGHT+IEHWN8e42GwQBxFY89j15A3l2TcV+QryJNJewInavabM7dzmeX+taQwOLPmxj1PdL/WYv3lcA396qk= X-Received: from pjbfr8.prod.google.com ([2002:a17:90a:e2c8:b0:32d:57a8:8ae6]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:1b50:b0:32d:a0f7:fa19 with SMTP id 98e67ed59e1d1-33b51375940mr33870345a91.17.1760377760845; Mon, 13 Oct 2025 10:49:20 -0700 (PDT) Date: Mon, 13 Oct 2025 10:49:19 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251010220403.987927-1-seanjc@google.com> <20251010220403.987927-3-seanjc@google.com> Message-ID: Subject: Re: [RFC PATCH 2/4] KVM: x86: Extract VMXON and EFER.SVME enablement to kernel From: Sean Christopherson To: Chao Gao Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "Kirill A. Shutemov" , Paolo Bonzini , linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, kvm@vger.kernel.org, Dan Williams , Xin Li , Kai Huang , Adrian Hunter Content-Type: text/plain; charset="us-ascii" On Mon, Oct 13, 2025, Chao Gao wrote: > >+void __init x86_virt_init(void) > >+{ > >+ cpu_emergency_virt_cb *vmx_cb = NULL, *svm_cb = NULL; > >+ > >+ if (x86_virt_is_vmx()) > >+ vmx_cb = x86_vmx_init(); > >+ > >+ if (x86_virt_is_svm()) > >+ svm_cb = x86_svm_init(); > >+ > >+ if (!vmx_cb && !svm_cb) > >+ return; > >+ > >+ if (WARN_ON_ONCE(vmx_cb && svm_cb)) > >+ return; > >+ > >+ cpu_emergency_register_virt_callback(vmx_cb ? : svm_cb); > > To be consistent with x86_virt_{get,put}_cpu(), perhaps we can have a common > emergency callback and let reboot.c call it directly, with the common callback > routing to svm/vmx code according to the hardware type. Oh, yeah, that's a much better idea, especially if x86_virt_init() runs unconditionally during boot (as proposed). cpu_emergency_disable_virtualization() can be dropped entirely (it'd just be a one-line wrapper).