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 0FDD73546D7; Wed, 20 May 2026 22:15:32 +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=1779315333; cv=none; b=DZzXWFy5zl4k13Gs4Z+GJAFakxhgbkmZPON9k+CImf2zGGnSY3C6i0tumv357orOWa8wQlxyZ1ganX5AbE1olxMY9DN6jvXeIv9jJgYQY9PJQytF5SCKx1Ukgjm0rf/Rk36bh8qtZzMH3iM9mUuyYFfes4P+brRohmqbBNxmjz4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779315333; c=relaxed/simple; bh=rT9nUsxSu2Ybme3gJs5c20aSGkkXIKB7Tp3hLLwdwlQ=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=eWVq3DrQQdaaO74P9S9mBJ9XanOcIgBDvOGvGRUMUPUoqSGxYPvhyoTAThIV2bZhP5/40f7RVqVXMVtxrVqzBBHuzW/qRlKjUMZaAle4Ckq5bd/FSYtDm8GChfBq4sRtrF5i30nomdrjMVqc2sWzQ0JVMKcp304GSYAeNx+uAaA= 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=Wr9TJuDN; 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="Wr9TJuDN" 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=rT9nUsxSu2Ybme3gJs5c20aSGkkXIKB7Tp3hLLwdwlQ=; b=Wr9TJuDNhfwD+ASl40rB6eLn5A XHmr9Ui/RLpFuNfW/MAyhI5S1mXY6h4F2wtyet+ZyqA8j+5e2s5f8Upd1vRumjnVyEPUEXyOMWAQG PNMtTcg0BcTYhYLF/q8OF+qbPFFefdSV+JuIzsPupvwDUacau3rb6Wgxfzh2BL+bezLuA/3aZ8j3u HPKtglkKriRmLnFc0OP7b43/19Hnbxp7l3VZdgS1mnTE00aVLoDkBj17Jc+7jUdlSKbxpUA3Tcem0 YbiordyimJUGn7kEkNWPlNKEqnPk2NMbk7Joefc+W79n2WaF+9EX95ha49rVAhKzFry6IwDJfakA/ nc1lyZNQ==; 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 1wPpCF-00000007fCZ-3fxu; Wed, 20 May 2026 22:15:24 +0000 Message-ID: <97b6edeb207a8c02b79b95d7e5091b37c8ce8025.camel@infradead.org> Subject: Re: [PATCH v3 16/41] x86/vmware: Nullify save/restore hooks when using VMware's 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 23:15:22 +0100 In-Reply-To: <20260515191942.1892718-17-seanjc@google.com> References: <20260515191942.1892718-1-seanjc@google.com> <20260515191942.1892718-17-seanjc@google.com> Content-Type: multipart/signed; micalg="sha-256"; protocol="application/pkcs7-signature"; boundary="=-jnx7qWHFD66TSDSU1e26" 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 --=-jnx7qWHFD66TSDSU1e26 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2026-05-15 at 12:19 -0700, Sean Christopherson wrote: > Nullify the sched_clock save/restore hooks when using VMware's version of > sched_clock.=C2=A0 This will allow extending paravirt_set_sched_clock() t= o set > the save/restore hooks, without having to simultaneously change the > behavior of VMware guests. >=20 > Note, it's not at all obvious that it's safe/correct for VMware guests to > do nothing on suspend/resume, but that's a pre-existing problem.=C2=A0 Le= ave it > for a VMware expert to sort out. >=20 > Signed-off-by: Sean Christopherson Reviewed-by: David Woodhouse --=-jnx7qWHFD66TSDSU1e26 Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgEFADCABgkqhkiG9w0BBwEAAKCCD9Aw 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