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 7A9362356D9; Fri, 25 Apr 2025 07:12:13 +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=1745565141; cv=none; b=rdEf51y4XLVbSjws7iS//a1rs3UsVytgwaKSdxksWsCMNsl2ehcE8oXdq9JsoZDqaOXPWC1+Z6S7IFwJ6fZTMAwtiXZbHhtFtG0Xgy5lKFy2j/53JcXjZNM7yS4V6mQEYgKBMPdyWaGwRoy2JIcfUQo65iVQBOkcQ1nASDGKCgc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745565141; c=relaxed/simple; bh=OWCgD4c53AWzLHmGkJc92XOEsxdbIrlrlIzldWXKc9c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eMEJ03S67yG/8dxLqUPgWwAK44aMYEAu+MiKPOV4SJrRD0yFA4Km8F/oNk6s1QuZoBKlfrOK3nqTAYJIv9ahzCCz2QsD2pWOzRWLBVhaBiXYjvJ/DdO8aKHMZDYQJEUqTfg+SEIj0dmm4VW5GUEhdaaUjMvpIjBMMhH8EzLj0mc= 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=Qw+6HPRA; 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="Qw+6HPRA" 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=/gz49BzCJiWld7uM47beLEzscI0nDdN8PKFhZbH8k1o=; b=Qw+6HPRAw2GLZXmgq20QS8wt0C txn/mVTO91ykn5tuFL/uuYfAuUYz48Q+lrxxQKWB2g9D74CKa+ah99c2oA9gm4GaeNVuoBaXtLVTE EIQdRwY5DRRXVVw52ts12pvJLUE9HqBbfk09qveKUwveCLkKx6mpx/Pt92hCzjodDWEFS+AyI99lE XynTiM71ri22QAuhPkA1dOyMyrvoIpydTtDNIbY90QgKhPVFKkLiMxiJwtrCmY2XuUv18oexVkyGa K2Yz5b9lN+AeV19kdukXXE8nn2xl4BF0X2TDbsW+JRVY+YdM++E1hfKHpu8kf3a1t1S5TXUufej/G ZpKgJFCw==; 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 1u8DE6-0000000BzpF-0oO3; Fri, 25 Apr 2025 07:11:58 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 9C8B63003C4; Fri, 25 Apr 2025 09:11:57 +0200 (CEST) Date: Fri, 25 Apr 2025 09:11:57 +0200 From: Peter Zijlstra To: =?iso-8859-1?Q?J=FCrgen_Gro=DF?= Cc: "Xin Li (Intel)" , 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: <20250425071157.GI18306@noisy.programming.kicks-ass.net> References: <20250422082216.1954310-1-xin@zytor.com> <20250422082216.1954310-22-xin@zytor.com> Precedence: bulk X-Mailing-List: kvm@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="xy1v71s9LdcW622N" Content-Disposition: inline In-Reply-To: --xy1v71s9LdcW622N Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Apr 22, 2025 at 11:57:01AM +0200, J=FCrgen Gro=DF wrote: > On 22.04.25 10:22, Xin Li (Intel) wrote: > > This becomes even more silly for trivial instructions like STI/CLI > > or in the worst case paravirt_nop(). >=20 > This is nonsense. What Jurgen says. Someone hasn't done their homework. static __always_inline void arch_local_irq_disable(void) { PVOP_ALT_VCALLEE0(irq.irq_disable, "cli;", ALT_NOT_XEN); } static __always_inline void arch_local_irq_enable(void) { PVOP_ALT_VCALLEE0(irq.irq_enable, "sti;", ALT_NOT_XEN); } That very much patches in STI/CLI directly when not Xen. --xy1v71s9LdcW622N Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEv3OU3/byMaA0LqWJdkfhpEvA5LoFAmgLNbQACgkQdkfhpEvA 5LoeWg/8D6ZI5w51DgwY+CTaX5PthgVGKgELCKDw5kBtAe3UxeF/H12T6L6a4XhK iSGZ9nZg17P5b2kv9cfXnslz/BqlOUjFfT+cuY64cIDvGXPqjbEcWxhHp/O7e34u L1wOXvlh5ZnWkVUPbeIFgLxCqPqOnGBpsq0LrQwaCxbEzkB5wKqS57h2ooqsrloQ V4WBwabMJ/lp704zpEgcqzWhM8zWydjPgfGuCZUTbVlvc4pgAGAwktnRd7ot+D4x n9UbVvBHSzW53t3RpsrzcQkVDGirtlcIipDUbPeIyTs+ArR+xfBiEl7QvXz1liAg GiJ7aNB/6PybXktHZBkEoRd/3sPBavWiOc1TMriCjWit/pNE+GJjUUozds3kRe/v pwMTYEbXlPYsgYv121YZpFaaz1ihVlIpnDj/6aqMTe+KQhAziId4CtU8pfSHYZi3 EgC+1PUUySs0LV4TkieDsk1zmfG1lDvWNe5UKyuFYKQ/A99Kg3BacBJHc+PrZDMq X7MfWZLRG++yhbcBPfHasl6Vg++GagMpoJLKp5zC9QaTUjRdvYm36SR0NvOC+BAt NPIq3H7qbBLYR0JBaJrgNSqe+1rPgJooo5PYg1Ozmv4q50Umlai3coKqls3pnTIe zwUVnBTjAszAW1zI3BcSrm5Ol912qJXA7AzxV+FRiKDC+kIRaU4= =t7cf -----END PGP SIGNATURE----- --xy1v71s9LdcW622N--