From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1J4RiR-0002wG-W7 for qemu-devel@nongnu.org; Mon, 17 Dec 2007 20:57:52 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1J4RiP-0002qr-Az for qemu-devel@nongnu.org; Mon, 17 Dec 2007 20:57:50 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1J4RiP-0002qj-2l for qemu-devel@nongnu.org; Mon, 17 Dec 2007 20:57:49 -0500 Received: from e36.co.us.ibm.com ([32.97.110.154]) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1J4RiO-0001XO-NA for qemu-devel@nongnu.org; Mon, 17 Dec 2007 20:57:48 -0500 Received: from d03relay02.boulder.ibm.com (d03relay02.boulder.ibm.com [9.17.195.227]) by e36.co.us.ibm.com (8.13.8/8.13.8) with ESMTP id lBI1v1PI003391 for ; Mon, 17 Dec 2007 20:57:01 -0500 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id lBI1v033154086 for ; Mon, 17 Dec 2007 18:57:00 -0700 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id lBI1v0Tg007907 for ; Mon, 17 Dec 2007 18:57:00 -0700 From: Hollis Blanchard In-Reply-To: <476247EB.9040003@linux.vnet.ibm.com> References: <11975745782686-git-send-email-ehrhardt@linux.vnet.ibm.com> <42DFA526FC41B1429CE7279EF83C6BDCAD01E3@pdsmsx415.ccr.corp.intel.com> <476247EB.9040003@linux.vnet.ibm.com> Content-Type: text/plain Date: Mon, 17 Dec 2007 19:56:58 -0600 Message-Id: <1197943018.5026.0.camel@diesel> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: [kvm-devel] [PATCH][UPDATE] kvm-userspace: sync icache for morearchitectures Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Christian Ehrhardt Cc: kvm-devel@lists.sourceforge.net, kvm-ppc-devel@lists.sourceforge.net, qemu-devel@nongnu.org On Fri, 2007-12-14 at 10:07 +0100, Christian Ehrhardt wrote: > > Hollis Blanchard wrote: > > A comment to explain why the icache needs flushing only in the KVM > case > > would be useful. Other than that I'm fine with it. > > > > Signed-off-by: Hollis Blanchard > AFAIK Plain qemu does not directly execute guest code on the > processor, > so the icache is not an issue for it. > Qemu itself has the flush_icache_range function only as helper for the > dynamic code generation. > But we may now write executable guest code with our intercepted mmio > handling that is directly executed when switching back to the guest > context, therefore we need that invalidation in the kvm case. > > For the case that I'm overlooking something in plain qemu, so that it > might need it too I add qemu-devel@nongnu.org for comments from there, > but currently I think to have it in #ifdef USE_KVM is the right way. > > > P.S. Hollis did you mean you would like to see a comment in the code > where that call takes place? Yes! Hopefully much shorter than this email... :-P -- Hollis Blanchard IBM Linux Technology Center