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 5A8A7346ADC; Wed, 20 May 2026 23:06:34 +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=1779318395; cv=none; b=k3QEzCQferh55KMRfKzimFHbWbJnF/MV3KeRRua7+BTlCwbajuTzpUMXXtyC9+6hGAuj4TShaShFSg7K5IaDINIGJUSmSiGwvOjnC/QJJX7f/RgOCPi/zkJDQXcMlBkTb14TD5sEP7jM8oz4mFrVgiXEUhlqHKXYdYu/tbAOQ5Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779318395; c=relaxed/simple; bh=4GQvxYPbI05Z1cj/1WHAcL42C7RPKsGJx4Urkvl1K7Q=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=KldAlduVZeZktJiQiUhhOQF1UZlmyiNIX8HuvHtWLinlXvha6eOjwQUohcqZJRyOZb0DfoS3RzilAiCobSYSdwxY0vY+x2ed1XljKQQyCMIe1ukeGTUoJNDp8M0TSLQsfiujXHE8+cECYQ5SpIlWFdueGTLIq5dGvPiCNAD5Uyg= 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=k4QnWiSB; 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="k4QnWiSB" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=MIME-Version:Content-Type:References: In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=4GQvxYPbI05Z1cj/1WHAcL42C7RPKsGJx4Urkvl1K7Q=; b=k4QnWiSBnVT26KV/1hox8Bc2Zw h1ug6i4QDDFzmM1Wh9T7JCcQfBsfGyrAfq6hqZpmaf+jbpJizEBTCL6RJISAN+3C4DxGza0zAwOvS pnPO2w4zr+FMIHUZvDFIFMC8THsNlepjNwn9dDI9zBcVCmR9nbPX7YS/HHTjMJALFu5xiGau39JT3 g3pSSv8rCr8QSFozr5/dF72kXNI2qtwpxkQKvg9P5r6hCk5Mk89exS5Wjqj1q9fsQlmnnoPyG8gla BGL+QTW3FsmGeV7rHl1L1F8CZBv7fe2334TuURMV6+GtWXlTdi7Ls8BdIWuFmWHAkQeQ3kT33sdmB F4G6SkGA==; Received: from 54-240-197-235.amazon.com ([54.240.197.235] helo=freeip.amazon.com) by casper.infradead.org with esmtpsa (Exim 4.99.1 #2 (Red Hat Linux)) id 1wPpzd-00000007iyd-3KJu; Wed, 20 May 2026 23:06:25 +0000 Message-ID: <0f85539ce23881f8a5c5a46c8cc633ef1ec3d162.camel@infradead.org> Subject: Re: [PATCH v3 25/41] x86/kvmclock: Hook clocksource.suspend/resume when kvmclock isn't sched_clock From: David Woodhouse To: Sean Christopherson , Kiryl Shutsemau , Paolo Bonzini , "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Ajay Kaher , Alexey Makhalov , Jan Kiszka , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Juergen Gross , Daniel Lezcano , Thomas Gleixner , John Stultz Cc: Rick Edgecombe , Vitaly Kuznetsov , Broadcom internal kernel review list , Boris Ostrovsky , Stephen Boyd , x86@kernel.org, linux-coco@lists.linux.dev, kvm@vger.kernel.org, linux-hyperv@vger.kernel.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, Michael Kelley , Tom Lendacky , Nikunj A Dadhania , Thomas Gleixner Date: Thu, 21 May 2026 00:06:24 +0100 In-Reply-To: <20260515191942.1892718-26-seanjc@google.com> References: <20260515191942.1892718-1-seanjc@google.com> <20260515191942.1892718-26-seanjc@google.com> Content-Type: multipart/signed; micalg="sha-256"; protocol="application/pkcs7-signature"; boundary="=-fsxfMtCF9Cp6c6pnaDKT" 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 --=-fsxfMtCF9Cp6c6pnaDKT Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2026-05-15 at 12:19 -0700, Sean Christopherson wrote: > Save/restore kvmclock across suspend/resume via clocksource hooks when > kvmclock isn't being used for sched_clock.=C2=A0 This will allow using kv= mclock > as a clocksource (or for wallclock!) without also using it for sched_cloc= k. >=20 > Signed-off-by: Sean Christopherson Reviewed-by: David Woodhouse --=-fsxfMtCF9Cp6c6pnaDKT Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgEFADCABgkqhkiG9w0BBwEAAKCCD9Aw ggSOMIIDdqADAgECAhAOmiw0ECVD4cWj5DqVrT9PMA0GCSqGSIb3DQEBCwUAMGUxCzAJBgNVBAYT AlVTMRUwEwYDVQQKEwxEaWdpQ2VydCBJbmMxGTAXBgNVBAsTEHd3dy5kaWdpY2VydC5jb20xJDAi BgNVBAMTG0RpZ2lDZXJ0IEFzc3VyZWQgSUQgUm9vdCBDQTAeFw0yNDAxMzAwMDAwMDBaFw0zMTEx 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