From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 2F83327A47F; Mon, 1 Jun 2026 21:49:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780350558; cv=none; b=tEx9vsoPfsh7Hsu1aJm9Hdg3cMxOlnoHLawMgL70ZHehp7vI7UCG6DMKYec/3Z6fpv4QmzdG760ey3pv5x0CRtp6vGbAJ2hbuDRgOkd96RCXBQ053pxII97AsHxjt/WOKFrfhBDks6W3ae/hqdQuYvefocfGGoysYS6DEX3RXkg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780350558; c=relaxed/simple; bh=pzYOc1WctnHJWbfi6MuvhZlFBL2ub6scSoq92qAqslw=; h=Message-ID:Subject:From:To:Cc:Date:in-reply-to:Content-Type: MIME-Version; b=FlJYklpevQBPfpPthEPRo3zahnJDl4uhFzR/LV3yHUUR3iolf9wLhFbxgJ5vJSkCdDfefEl8Zoqe2FjhXGvWnpUI1uvA3ijeSMIkors2lBvaW2fSbMHaOxWDdlIxKp0EdVO2pD7afoez+nDJOZdEVXPVn/+ptXMUg0pSV4i+Ob0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=casper.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=UP9RiNMG; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=casper.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="UP9RiNMG" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=MIME-Version:Content-Type:in-reply-to: Date:Cc:To:From:Subject:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:References; bh=7F3/Z3S4Ohu4+WmzhSzzI4cWIlxfQO/JOD7SKgruhD0=; b=UP9RiNMGxszqf6cpNGmSpW/Olq wJCrrH93bWGbwyG9cYajFAiiCq/1OnvoCwvP5y8IyiqNChPfpbNocauWGNoZJHRzTimocBwlg+xN4 UGdN0zGR9eeBYY8not2P3zM54tWs0T+YrQMBA14yqi5EQTAsUELxepenYbY8VkK/+pZki/ZQL/ak9 0wqejZMgSkMwtnEMnPfYAI2mfzFi1VHTwpom+eH7Lm3rd3apkI84PW0CdNTnmdj3IbjVZMMR3WyVW XEKglOeWdelUYadOr7i6d8QrJiUFKyU1lFiFPKaV3HEys7SiEkVI5RFpmOsOTmnEBxeDL53HFXx/U hNHFj76g==; Received: from [2001:8b0:10b:5:5b40:b57d:669c:36f4] (helo=u09cd745991455d.ant.amazon.com) by casper.infradead.org with esmtpsa (Exim 4.99.1 #2 (Red Hat Linux)) id 1wUAVL-00000000p2a-2TBZ; Mon, 01 Jun 2026 21:49:04 +0000 Message-ID: Subject: Re: [PATCH v4 8/47] x86/tsc: Add dedicated hypervisor hooks for getting known TSC/CPU frequencies From: David Woodhouse To: seanjc@google.com Cc: pbonzini@redhat.com, tglx@kernel.org, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, kas@kernel.org, kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, ajay.kaher@broadcom.com, alexey.makhalov@broadcom.com, jan.kiszka@siemens.com, luto@kernel.org, peterz@infradead.org, jgross@suse.com, daniel.lezcano@kernel.org, jstultz@google.com, hpa@zytor.com, rick.p.edgecombe@intel.com, vkuznets@redhat.com, bcm-kernel-feedback-list@broadcom.com, boris.ostrovsky@oracle.com, sboyd@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, linux-hyperv@vger.kernel.org, virtualization@lists.linux.dev, xen-devel@lists.xenproject.org, dwmw@amazon.co.uk, thomas.lendacky@amd.com, nikunj@amd.com, dwmw2@infradead.org, mhklinux@outlook.com, tglx@linutronix.de Date: Mon, 01 Jun 2026 22:49:02 +0100 in-reply-to: <20260529144435.704127-9-seanjc@google.com> Content-Type: multipart/signed; micalg="sha-256"; protocol="application/pkcs7-signature"; boundary="=-KfGeQos5ntguCu9qjbbK" User-Agent: Evolution 3.52.3-0ubuntu1.1 Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html --=-KfGeQos5ntguCu9qjbbK Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 29 May 2026 07:43:55 -0700, Sean Christopherson wrote: > Add dedicated hypervisor hooks for getting known TSC/CPU frequencies > instead of overriding seemingly generic platform hooks, and explicitly > priotize hypervisor-provided frequencies over native methods, but do NOT > clobber the frequency obtained from trusted firmware. While shuffling th= e > hooks around is arguably "six of one, half dozen of the other", scoping > them to x86_hyper_init makes their purpose more obvious, and allows for > explicitly defining the priority of sources (as is done here). > > Cc: David Woodhouse > Signed-off-by: Sean Christopherson Reviewed-by: David Woodhouse --=-KfGeQos5ntguCu9qjbbK Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgEFADCABgkqhkiG9w0BBwEAAKCCD9Aw ggSOMIIDdqADAgECAhAOmiw0ECVD4cWj5DqVrT9PMA0GCSqGSIb3DQEBCwUAMGUxCzAJBgNVBAYT AlVTMRUwEwYDVQQKEwxEaWdpQ2VydCBJbmMxGTAXBgNVBAsTEHd3dy5kaWdpY2VydC5jb20xJDAi BgNVBAMTG0RpZ2lDZXJ0IEFzc3VyZWQgSUQgUm9vdCBDQTAeFw0yNDAxMzAwMDAwMDBaFw0zMTEx MDkyMzU5NTlaMEExCzAJBgNVBAYTAkFVMRAwDgYDVQQKEwdWZXJva2V5MSAwHgYDVQQDExdWZXJv a2V5IFNlY3VyZSBFbWFpbCBHMjCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAMjvgLKj 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