From nobody Mon Feb 9 05:59:43 2026 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 37E90198851 for ; Thu, 28 Nov 2024 01:35:04 +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=1732757705; cv=none; b=PBQ+yjJVLh/HkDwnTG5YnkghG4PI/xbR+wrmG0NNXV/rQbSsw8pw4KBZyFAZyGVkesEmITDi73pnNbCNf02+GUvLUqcE0IU8EH/NeaufHA6umIfO+ZRwiHLDAedYh8/QQw3RfmrOHTbrk+xsNsF82bsO2a5fB9GKIvzz3VUz8O4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732757705; c=relaxed/simple; bh=21B9ts389TeEE9vha5UXItt4ArqBvD8PoHd8CLYe9JY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=INzkTBuR96SRIwapFImLMrUHUbxdbhyEhmg5ze5a34D7n0eMCfsky7/C/wn+sFDqRvmxy8CAavB/9gi8a3ZdGyZpjRlHTO7UcRI+qWvNZ+5zp1jACa9rnSvXlLbLmnm6uOtrk7aBwfyGW035N1tNx+AIK2nAg6QBiB9/HpkSOLc= 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=LPGsfbfb; 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="LPGsfbfb" Received: by mail-pj1-f74.google.com with SMTP id 98e67ed59e1d1-2ee237d13b4so524054a91.1 for ; Wed, 27 Nov 2024 17:35:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1732757703; x=1733362503; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=a/9iAaldSIYNoaw8wlfvun5f6TVnKjV0yuck5Iu36H8=; b=LPGsfbfb5OX9lxevSNgFhBRQlUA3kV+qGbQ2VZGUVD3MozmTHLNLb1C8YqRtyEs27P knlVWeE4ypEWI41DZh/X42tWzHhNHNcQwABjhJYAqq38CsD8UZaPffp2mudi/FS/Jrg4 K+OETWdYacj9O9WbC9UC1St76sMhqHtyfRW2WLees8nrDU3qotbbxrfmiwAsTPVLjHRV iH2MpflAtRuLs1oNSSR5l0tDNTjwxYYtH3Vee1UuRLlKkpuhwqWex4zH1MIcELc4HaGN vluH60TxF2ssi3MW0A4SfGHnMdQ1CXaW/Z7PmsN80tBtCkpb/Tc5/ENgWli43nnPNFP+ 6aVw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1732757703; x=1733362503; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=a/9iAaldSIYNoaw8wlfvun5f6TVnKjV0yuck5Iu36H8=; b=Qxdr92+eqn7FUqvod13KPlMYRCT6W2n6v5ONYe8sfmK8IVcBlbxXdgSZd44MdkBqK6 4XAW/A4SxK4lReTjrWFGn38fzxhiSZbG3UE8q+dlYH6N8lQPz93O99W5wPsQIaXDgcUB ofwqU+bU3ObD2R0TL0LydweeqFxhS+FCIOrhyXHQXXo+oQhW5YN/ih04Dqd4KG9wdIW3 FDxi/EH8/LbgZle78f3jE1RXys038l28VOwibSK9mXtsb4z9VFRKAmhHs7SvUv/BdiCP 7OcR8m9yYsk1lEPugZFKF3uYVXLxexOmifBEX03x4ikWFPfItAq3eknhFn6JknkY001g e9Gg== X-Forwarded-Encrypted: i=1; AJvYcCXynn5wkelT2B5KKZBZkq3BWEhGyeEYt0c6rrXvlCpS6qYMA9Q0HBCvL4leEPousAqXBdIL2J+3H5w2yn4=@vger.kernel.org X-Gm-Message-State: AOJu0YxpOOijCLry2BIpA5Wc0Rdxn3WR99xtNwMzeWBwTcRM2u/yZ0q9 w3Nfy24HEl9joOXjFeL1rwh0Evkp53FSigRXENQWt7n23Mp+Fr+tzW62m3jBnBqgV2UDcg7UWq6 8Ow== X-Google-Smtp-Source: AGHT+IEEgaZtWbIrOrUz2mxSm9EPBvK+IDwvuT3hAKykt6QoSkNbBU7y039G0akcnYFaBbsuxXcjj7GaWGw= X-Received: from pjbsp6.prod.google.com ([2002:a17:90b:52c6:b0:2ea:5dea:eafa]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:2690:b0:2ea:7755:a0fa with SMTP id 98e67ed59e1d1-2ee08e9d433mr7018289a91.7.1732757703634; Wed, 27 Nov 2024 17:35:03 -0800 (PST) Reply-To: Sean Christopherson Date: Wed, 27 Nov 2024 17:33:45 -0800 In-Reply-To: <20241128013424.4096668-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241128013424.4096668-1-seanjc@google.com> X-Mailer: git-send-email 2.47.0.338.g60cca15819-goog Message-ID: <20241128013424.4096668-19-seanjc@google.com> Subject: [PATCH v3 18/57] KVM: x86: Zero out PV features cache when the CPUID leaf is not present From: Sean Christopherson To: Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Jarkko Sakkinen Cc: kvm@vger.kernel.org, linux-sgx@vger.kernel.org, linux-kernel@vger.kernel.org, Maxim Levitsky , Hou Wenlong , Xiaoyao Li , Kechen Lu , Oliver Upton , Binbin Wu , Yang Weijiang , Robert Hoo Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Clear KVM's PV feature cache prior when processing a new guest CPUID so that KVM doesn't keep a stale cache entry if userspace does KVM_SET_CPUID2 multiple times, once with a PV features entry, and a second time without. Fixes: 66570e966dd9 ("kvm: x86: only provide PV features if enabled in gues= t's CPUID") Cc: Oliver Upton Reviewed-by: Maxim Levitsky Signed-off-by: Sean Christopherson --- arch/x86/kvm/cpuid.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 27919c8f438b..a94234637e09 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -251,6 +251,8 @@ void kvm_update_pv_runtime(struct kvm_vcpu *vcpu) { struct kvm_cpuid_entry2 *best =3D kvm_find_kvm_cpuid_features(vcpu); =20 + vcpu->arch.pv_cpuid.features =3D 0; + /* * save the feature bitmap to avoid cpuid lookup for every PV * operation --=20 2.47.0.338.g60cca15819-goog