From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 1A5B712CD8B; Fri, 25 Apr 2025 12:33:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745584410; cv=none; b=KDuUWVafjitUa4Y/UJJ1zJiCcxCd/PqDHll+eJYK1s2coJTqJBMnZu0mLh9+Nu2gbUw9l15Woc750oI61mrNqp9v3pH+L0doAjPNRid1HcTYy7tkvwUefvAePNSPbQ8S0m0my1OTTyhUKwG0q8t4xB/ybo7j4drg3RoeIyskebw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745584410; c=relaxed/simple; bh=z0kssRXr0Jmr2iLuPqygq8fHDe3P+7Q6+7xMZ7CRFpA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=iX53u3wdIfTBtEkqns/iG4Lwz2tVMr4O/O21tpOKpAYFU2ekZ3cdc88hoL8MQ4IbqvRnCbdC6ot+uXqi/4DpNwsaHfPjYeOeZEWcR4IWY7DqtxDxio96djbklEjs/6OR91X1ABUC5ewlWBB0+fE0d8dH9CN+H6T5h+E37NJmYCc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=n62i0DvK; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="n62i0DvK" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=z0kssRXr0Jmr2iLuPqygq8fHDe3P+7Q6+7xMZ7CRFpA=; b=n62i0DvKUkkS19M6Grw/IA6BJM 6eax7WEzMDhdsLLdBaVpyql0sL3uwAA/S4ABBYyHfp8Tx/iU0ee0EuTw7NJfGf9EI8UsjXrlSl0sS 02tBYqSgzmjI/Kny3gI739/JKlgl+9wGdEidVTiMFctgk47RLsTlqNTkCUR+iW8cVDyF62mXAMwh5 XkywTMBNuRYpIwM9+ushQW73ekmtzH4pzyRk9psYN+bzsnJD1auXiTevc+ivI+Y1ZKlYKr7ewsVRG jovxOw3NEqLfi+p+LosTspxc/ZhCArckwjJxCRVQhZyFjxgfcqmpAHeIJnZG6UgRJMQ7uJJh6ZqZe G7VOYhcg==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.1 #2 (Red Hat Linux)) id 1u8IF4-0000000C2S5-1fLP; Fri, 25 Apr 2025 12:33:18 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id DA9983003C4; Fri, 25 Apr 2025 14:33:17 +0200 (CEST) Date: Fri, 25 Apr 2025 14:33:17 +0200 From: Peter Zijlstra To: =?iso-8859-1?Q?J=FCrgen_Gro=DF?= Cc: Xin Li , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-hyperv@vger.kernel.org, virtualization@lists.linux.dev, linux-pm@vger.kernel.org, linux-edac@vger.kernel.org, xen-devel@lists.xenproject.org, linux-acpi@vger.kernel.org, linux-hwmon@vger.kernel.org, netdev@vger.kernel.org, platform-driver-x86@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, acme@kernel.org, andrew.cooper3@citrix.com, namhyung@kernel.org, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, irogers@google.com, adrian.hunter@intel.com, kan.liang@linux.intel.com, wei.liu@kernel.org, ajay.kaher@broadcom.com, bcm-kernel-feedback-list@broadcom.com, tony.luck@intel.com, pbonzini@redhat.com, vkuznets@redhat.com, seanjc@google.com, luto@kernel.org, boris.ostrovsky@oracle.com, kys@microsoft.com, haiyangz@microsoft.com, decui@microsoft.com Subject: Re: [RFC PATCH v2 21/34] x86/msr: Utilize the alternatives mechanism to write MSR Message-ID: <20250425123317.GB22125@noisy.programming.kicks-ass.net> References: <20250422082216.1954310-1-xin@zytor.com> <20250422082216.1954310-22-xin@zytor.com> <37c88ea3-dd24-4607-9ee1-0f19025aaef3@suse.com> Precedence: bulk X-Mailing-List: linux-hwmon@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="/MHZas7e8A04P/yf" Content-Disposition: inline In-Reply-To: <37c88ea3-dd24-4607-9ee1-0f19025aaef3@suse.com> --/MHZas7e8A04P/yf Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Apr 23, 2025 at 06:05:19PM +0200, J=FCrgen Gro=DF wrote: > > It's not a major change, but when it is patched to use the immediate > > form MSR write instruction, it's straightforwardly streamlined. >=20 > It should be rather easy to switch the current wrmsr/rdmsr paravirt patch= ing > locations to use the rdmsr/wrmsr instructions instead of doing a call to > native_*msr(). Right, just make the Xen functions asm stubs that expect the instruction registers instead of C-abi and ALT_NOT_XEN the thing. Shouldn't be hard at all. --/MHZas7e8A04P/yf Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEv3OU3/byMaA0LqWJdkfhpEvA5LoFAmgLgQUACgkQdkfhpEvA 5LqJKRAAkGelIfMDPEkg613aLM0RL5GIPigFIL9+IaLhypRMpJMp1rKIwy8kLaRd NwdJ0yX6iqAzFF/AHn3KvVp7MxNCeDWNTXTcCpxuCSB8NoKfph2JduGzhUylWdg3 AhemoMrgzBgwkVVk2mDD2kvewJ0Axr2isfs+ugJLAo+GvKhnV+qJRvSE/FB0V7XV LC+r1B6ZXIcUBjvYOW2JbRYPW/UDT/LS9CZDWr2pu+A3jJ8vmlOwAb0Yeh3/2yKB /LdGM2PIII/0x66JaVvZawFSLjeUT18HxLAAh8MDDLgWCiwp+Uk3RzgrnaSj9oC0 6uV/J7czytoK4haaV70zPcWqzZPIurtpgcG9AynaG05VjJ5ARgEG6EFJd91NnbM+ 7dZWXM6y1PI6IFuh1ldUJUD3YnEd3VuXAWaYE4aBr63rXaUYuVpAKRUY0NFZmxHw KGaVmss4AtUGeDBTPMvYyx+d1BTxPiYVeVbLzodtjl/mQPfpne5vlQomBolxd/0a fkeL0zUZoVgLfndRNVN+dIa2cPWo+BHNNM8tI92aFQ0YrxaTpdSjrOJ0bobnBUch deYEsdgKUEpUcFZqcp/ox1cc73kPeJ9365RwavrAN8sZIUSs+vvtu36/WIVI12eK qw6upySrPM0KLVTItTbNxKmS5uvFrc2fDPMAoru3P2Y5VkKPa2Q= =6Oyb -----END PGP SIGNATURE----- --/MHZas7e8A04P/yf--