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[209.132.180.67]) by mx.google.com with ESMTP id f10-v6si4666765pln.401.2018.02.05.00.57.37; Mon, 05 Feb 2018 00:57:51 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@infradead.org header.s=bombadil.20170209 header.b=i/jCP9Kk; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752647AbeBEIzr (ORCPT + 99 others); Mon, 5 Feb 2018 03:55:47 -0500 Received: from bombadil.infradead.org ([65.50.211.133]:35609 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752199AbeBEIzk (ORCPT ); Mon, 5 Feb 2018 03:55:40 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; 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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=x9Om08tjiWHEdtc5RZQ7ucnfV2BmEvMMrdQvocB7Jbc=; b=i/jCP9KkuJhxYVPG9Y+zT6Bzj 6vxIMAk02KKDcamJhLmmPFZa1ncJJJ8reSoXz8WgOrpn9oRAT/Cm491Lbk78433TOLvRGQUmdbNpM xfCZwhIU6NtJ8kocyME76OA9UEIBu+ipz7aCuuZpCPZdvv/dcbI8R9tHeBbuJXqQynbEJH1rPifWz 1uztndhiN3ZqLSvWpKGVWg4rGKFkmE91mTJWMUUSuIXupEGEpM6H/2NAGAFf+TjMm2ZSUWGMSxqwT dbIPALDptUJ5sep18W9K98Y/Rlx9j7tP0rGiMwZtaeKTFflejWpvpJZTxdWDXem1E+NY/oRnhMkEZ SS4PC6dTg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.89 #1 (Red Hat Linux)) id 1eicYi-0003lO-62; Mon, 05 Feb 2018 08:55:28 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 76A6D2029F9F9; Mon, 5 Feb 2018 09:55:26 +0100 (CET) Date: Mon, 5 Feb 2018 09:55:26 +0100 From: Peter Zijlstra To: David Woodhouse Cc: Alan Cox , Linus Torvalds , Thomas Gleixner , KarimAllah Ahmed , sironi@amazon.de, the arch/x86 maintainers , KVM list , Paolo Bonzini , Linux Kernel Mailing List , Borislav Petkov Subject: Re: [PATCH] KVM: x86: Reduce retpoline performance impact in slot_handle_level_range() Message-ID: <20180205085526.GG2249@hirez.programming.kicks-ass.net> References: <1517583559-424-1-git-send-email-dwmw@amazon.co.uk> <1517599033.31953.71.camel@infradead.org> <20180202212321.5186c13c@alans-desktop> <1517669207.31953.120.camel@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1517669207.31953.120.camel@infradead.org> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 03, 2018 at 02:46:47PM +0000, David Woodhouse wrote: > Yeah. I'm keen on being able to use something like alternatives to > *change* 'usualfunction' at runtime though. I suspect it'll be a win > for stuff like dma_ops. That shouldn't be too hard to implement.