From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [semi-urgent Xen CS question] Re: git commit 9fd67b4ed0714ab718f1f9bd14c344af336a6df7 (x86-64: Give vvars their own page) breaks Xen PV guests (64-bit). Date: Tue, 2 Aug 2011 10:10:30 -0400 Message-ID: <20110802141030.GK11133@dumpdata.com> References: <4E30317E.30706@goop.org> <4E3048B4.6020805@goop.org> <4E30FCAE.4070906@goop.org> <4E32D257.6090606@goop.org> <20110731185657.GA3747@dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Andrew Lutomirski Cc: Jeremy Fitzhardinge , xen-devel@lists.xensource.com, Keir Fraser List-Id: xen-devel@lists.xenproject.org On Sun, Jul 31, 2011 at 03:14:59PM -0400, Andrew Lutomirski wrote: > Actually I'm waiting b/c I'm defending my thesis tomorrow. I might get v2 > out before then, but no guarantee. Oooh, yeah take care of your thesis first. And then celebrate by writting more patches :-) > On Jul 31, 2011 2:57 PM, "Konrad Rzeszutek Wilk" > wrote: > > On Fri, Jul 29, 2011 at 08:31:35AM -0700, Jeremy Fitzhardinge wrote: > >> On 07/29/2011 05:51 AM, Andrew Lutomirski wrote: > >> > VCGF_in_syscall: gettimeofday() (the syscall version) takes 593 ns. > >> > Without VCGF_in_syscall, it's 712 ns. > >> > > >> > I'd argue for using my original approach of adding a user_64bit_mode > >> > function -- I think it's a legitimate cleanup and Xen, for better or > >> > worse, really does have two long mode CPL 3 selectors. If we removed > >> > selector 6 from the GDT, that would be a different story, but that > >> > would probably be a more intrusive change. > >> > >> Sigh. Yeah, let's see what happens. > > > > So.. roll with Andrew's patches? I think Andrew is just waiting for the > word > > from you whether to repost the patches so that x86 maintainers can take a > look > > at them..