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 A527D3750AF; Wed, 20 May 2026 22:28:00 +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=1779316083; cv=none; b=pTC1Uc+xd9COUC86ERL4j7iTn5puILvZSmVdDLlD1KG/kQir4yfkZukY7mjk7GeEaartbQkkUk3B88siJcCNgkEGbDksBQi/Bpr7i1kHLPDRLuVRqxMQ9gdhu4YU4ClFEREt7IV+wO+AU68HYXHl41yhEngkqj0oImomXDDAxrc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779316083; c=relaxed/simple; bh=u/o0dx1DTtvDMEvtqsgv6xvzgr05hh9iTv1UVVaweM8=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=fvBGjDLlA5v/FyIyYtSbkgHnlKsdu3dNVLsvbNd2HxVeubBS8I2v9aK808aEEEP+zJDEz64uneHSC+iuQNg3ILivp7U+ZdvhUki7VISulG73VUSvrGCQOaT+YFYgH0fZo6LEt58aKwy9JI3051waz/0pphTx3meObjJwrmm0L2s= 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=Pf4BtEcR; 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="Pf4BtEcR" 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=u/o0dx1DTtvDMEvtqsgv6xvzgr05hh9iTv1UVVaweM8=; b=Pf4BtEcR1l2SN8va8ePyeHXTYd UdkibwUXr3vheIE7ybNGI6jziKF5IfUWKppllOgstw5tkz+n0qfSv+hNKT7YcN7cCCn8TvAFwomwq NmCKWjlehElWaf42JeesPOgqI9pcYK0u1BCIRWRA9KAKckQd1T6d31MK4erjJfq6ody+beqE3EAOQ 6qDdakbhleQXU1geIXfWCSfzwuzCS9n0Db1K5q9D/dYU/8dAPV/ZtQQ7pGy+sYODX+dEBpFqY6SjG y+O4Q7VuoLvl6IXC61Zzydc+xLeaF8LAQiClSFyfNIG1E6CxiBu/RfFlOzTOxCpJaZUgBmZgU1rOz qnClQF2w==; Received: from 54-240-197-227.amazon.com ([54.240.197.227] helo=freeip.amazon.com) by casper.infradead.org with esmtpsa (Exim 4.99.1 #2 (Red Hat Linux)) id 1wPpOK-00000007guY-2eBr; Wed, 20 May 2026 22:27:52 +0000 Message-ID: <28efabc0618268447144db5068cdf377afbea506.camel@infradead.org> Subject: Re: [PATCH v3 17/41] x86/tsc: WARN if TSC sched_clock save/restore used with PV 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: Wed, 20 May 2026 23:27:50 +0100 In-Reply-To: <20260515191942.1892718-18-seanjc@google.com> References: <20260515191942.1892718-1-seanjc@google.com> <20260515191942.1892718-18-seanjc@google.com> Content-Type: multipart/signed; micalg="sha-256"; protocol="application/pkcs7-signature"; boundary="=-WbaHQ7O15QtA6Zt9MU0Q" 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 --=-WbaHQ7O15QtA6Zt9MU0Q Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2026-05-15 at 12:19 -0700, Sean Christopherson wrote: > Now that all PV clocksources override the sched_clock save/restore hooks > when overriding sched_clock, WARN if the "default" TSC hooks are invoked > when using a PV sched_clock, e.g. to guard against regressions. >=20 > Signed-off-by: Sean Christopherson Reviewed-by: David Woodhouse --=-WbaHQ7O15QtA6Zt9MU0Q 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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