From mboxrd@z Thu Jan 1 00:00:00 1970 From: Don Slutz Subject: Re: ioport 0x12 logfile writing Date: Tue, 24 Dec 2013 11:34:21 -0500 Message-ID: <52B9B78D.5040709@terremark.com> References: <6035A0D088A63A46850C3988ED045A4B68561A9C@BITCOM1.int.sbss.com.au> <9AAE0902D5BC7E449B7C8E4E778ABCD01C1D77@AMSPEX01CL01.citrite.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1VvUy5-0007cK-HL for xen-devel@lists.xenproject.org; Tue, 24 Dec 2013 16:36:29 +0000 In-Reply-To: <9AAE0902D5BC7E449B7C8E4E778ABCD01C1D77@AMSPEX01CL01.citrite.net> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Paul Durrant Cc: "xen-devel@lists.xenproject.org" , James Harper List-Id: xen-devel@lists.xenproject.org On 12/24/13 04:10, Paul Durrant wrote: >> -----Original Message----- >> From: xen-devel-bounces@lists.xen.org [mailto:xen-devel- >> bounces@lists.xen.org] On Behalf Of James Harper >> Sent: 24 December 2013 06:28 >> To: xen-devel@lists.xenproject.org >> Subject: [Xen-devel] ioport 0x12 logfile writing >> >> Under xen 4.1 and the old qemu I could write to /var/log/xen/qemu-dm- >> .log from inside the vm by writing to ioport 0x12. Is that >> functionality replaced in any way in qemu upstream? Does qemu have its >> own logging mechanism? >> > That logging mechanism (via qemu tracing: see http://repo.or.cz/w/qemu/stefanha.git/blob_plain/refs/heads/tracing:/docs/tracing.txt) is still there, but unfortunately off by default. I think recent xen builds now compile upstream qemu with a stderr trace backend by default at least so all you should need to do is create a events file by doing: > > Echo xen_platform_log > /tmp/events > > And then adding "-trace events=/tmp/events" to your qemu command line via your xl.cfg: > > device_model_args = ['-trace', 'events=/tmp/events'] > > Port 0x12 logging should then appear as before. > > Paul QEMU tracing is on only for "debug=y" builds (tools/Makefile): ifeq ($(debug),y) QEMU_XEN_ENABLE_DEBUG := --enable-debug --enable-trace-backend=stderr else QEMU_XEN_ENABLE_DEBUG := endif -Don Slutz > > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel