From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x227gxvB9cl1S2U4ZOOqyeA4UE6kcG2caZ8o8iLhqC6I3z3C6LT8LGokyi3VH+r6mahqqiIaL ARC-Seal: i=1; a=rsa-sha256; t=1517401855; cv=none; d=google.com; s=arc-20160816; b=N8CgAHfQQYhlf3fBhexjOPq6qrBEsyVTFlfkLSXY/+kaW8zB0uh1CdkIH7B6epT12T 9m6OzcN0uTuZeNIqDE9NuH88xDk6ClwG7qeVBTsmLV3/tsByRzU+tWQ6OJLtrsYGHOWL 2HIPofML0qipw3vBZEW3xcWr2C7KBLdgHJOL+cvGhYjcJkEsOtrUgtGGEpcP0n8QB6QO GEbc+qDuzIr1HGtP4LS9vWN8XuA7bTnJg6Q9unQJZWHVYZfBYym8tG37jnDKjcVhKBWD gZX1kcZ+AVLCjmH2ZAJKcSZhPt/2UVPWTmns9o0Zklar2JNBHM/mBklMczR5h+/CC4Kz u+tQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-transfer-encoding :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:arc-authentication-results; bh=Qf4GLMSXNT13KbUMkKBrz/G6hEqancG+iwYZY58JxtE=; b=0mv6MmEoMEObo2NYb3SUUxdnqCt3WUjtgAX6/ubcsJqi0HQVMK2+Qv91LsYdzJorpf x87PetHaxP5id9aGCQauRIKfz6l84EEQMQma6rM+VqHmi0UfpJS5UHWzjJjXB590GdxN SMK+iBaC8JPzGsKVOp7Rg+WnDIYqOPLyE8xzbOzv9VO4reQv+fQ951nNGRDyyIRM+S0p JSsuJ3NBX1jhJ5GxMkGftw3yhDjdl3J1EL+3F4qW1ZdTUvB7U2TWO4iFQ6njJLZhKP/c csbhsPt4wAyQodSchQAhF8oheoliVnd7NCVqHBADRpCZs0dv8CbT416JM7di+PjQFGJ1 d08w== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of dgilbert@redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=dgilbert@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of dgilbert@redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=dgilbert@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Date: Wed, 31 Jan 2018 12:30:36 +0000 From: "Dr. David Alan Gilbert" To: Borislav Petkov Cc: Thomas Gleixner , Christophe de Dinechin , Alan Cox , Linus Torvalds , David Woodhouse , Arjan van de Ven , Eduardo Habkost , KarimAllah Ahmed , Linux Kernel Mailing List , Andi Kleen , Andrea Arcangeli , Andy Lutomirski , Ashok Raj , Asit Mallick , Dan Williams , Dave Hansen , Greg Kroah-Hartman , "H . Peter Anvin" , Ingo Molnar , Janakarajan Natarajan , Joerg Roedel , Jun Nakajima , Laura Abbott , Masami Hiramatsu , Paolo Bonzini , Peter Zijlstra , Radim =?utf-8?B?S3LEjW3DocWZ?= , Tim Chen , Tom Lendacky , KVM list , the arch/x86 maintainers Subject: Re: [RFC,05/10] x86/speculation: Add basic IBRS support infrastructure Message-ID: <20180131123036.GD2521@work-vm> References: <1517257022.18619.30.camel@infradead.org> <20180129204256.GV25150@localhost.localdomain> <31415b7f-9c76-c102-86cd-6bf4e23e3aee@linux.intel.com> <1517259759.18619.38.camel@infradead.org> <20180130204623.583b1a7a@alans-desktop> <200C59E8-80F3-4FEC-BA3B-E6A56FA12C74@dinechin.org> <20180131110406.GB2521@work-vm> <20180131115211.2cxz2xj6elv37p6t@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20180131115211.2cxz2xj6elv37p6t@pd.tnic> User-Agent: Mutt/1.9.1 (2017-09-22) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1590140581449802182?= X-GMAIL-MSGID: =?utf-8?q?1591111167500179023?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: * Borislav Petkov (bp@suse.de) wrote: > On Wed, Jan 31, 2018 at 11:04:07AM +0000, Dr. David Alan Gilbert wrote: > > That half is the easy bit, we've already got that (thanks to Eduardo), > > QEMU has -IBRS variants of CPU types, so if you start a VM with > > -cpu Broadwell-IBRS > > Eww, a CPU model with a specific feature bit. I hope you guys don't add > a model like that for every CPU feature. Indeed, it's only for this weird case where you suddenly need to change it. Dave > -- > Regards/Gruss, > Boris. > > SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) > -- -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK