From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:50743) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UKk47-0001fH-Q3 for qemu-devel@nongnu.org; Wed, 27 Mar 2013 02:42:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UKk45-0000dH-8T for qemu-devel@nongnu.org; Wed, 27 Mar 2013 02:42:31 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:43242) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UKjkj-0003Fq-Na for qemu-devel@nongnu.org; Wed, 27 Mar 2013 02:22:30 -0400 Received: from m2.gw.fujitsu.co.jp (unknown [10.0.50.72]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id AF0183EE0AE for ; Wed, 27 Mar 2013 15:22:27 +0900 (JST) Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 9717545DE4E for ; Wed, 27 Mar 2013 15:22:27 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 808D745DE50 for ; Wed, 27 Mar 2013 15:22:27 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 740571DB8038 for ; Wed, 27 Mar 2013 15:22:27 +0900 (JST) Received: from g01jpexchkw30.g01.fujitsu.local (g01jpexchkw30.g01.fujitsu.local [10.0.193.113]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 3031D1DB803C for ; Wed, 27 Mar 2013 15:22:27 +0900 (JST) Message-ID: <51529001.8040102@jp.fujitsu.com> Date: Wed, 27 Mar 2013 15:21:53 +0900 From: Kazuya Saito MIME-Version: 1.0 References: <514C1560.1020406@jp.fujitsu.com> <514C3CE1.3000100@redhat.com> <51514AA1.9040008@jp.fujitsu.com> <51514B2F.6090304@redhat.com> In-Reply-To: <51514B2F.6090304@redhat.com> Content-Type: text/plain; charset="ISO-2022-JP" Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 0/5] Add some tracepoints for clarification of the cause of troubles List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: qemu-devel@nongnu.org (2013/03/26 16:15), Paolo Bonzini wrote: > Il 26/03/2013 08:13, Kazuya Saito ha scritto: >>>> >>>> I'm not sure 4-5 are that useful, but the first 3 patches are definitely >>>> good stuff. >> Thanks. I'll modify the patch you pointed out about CPU number and >> re-post it. >> I'd like to add tracepoints to the virtual device creation/deletion >> part. I had an issue that when a Windows guest OS booted up, it didn't >> have a virtual NIC device which it should have had. It took us time to >> figure out which the guest OS or the QEMU had the issue. If I have >> had the tracepoints in the virtual device creation/deletion should have >> eased the situation much better. > > Wouldn't you get the same information from the command line? I think the information you said is different from what I meant. The information I wanted to know is whether QEMU creates/deletes a device successfully or not. We cannot get it from the command line. I was sure I specified a NIC device for the guest, but the Windows guest didn't have it when it booted. There were two possibilities. One was QEMU failed to create the NIC device, and the other was QEMU created it successfully and the Windows guest failed to detect it. Since QEMU output limited message at the moment, it was difficult to prove that it was not QEMU's issue. I took a coredump of the QEMU and proved the QEMU must have a valid structures for the NIC device. I believe the tracepoints could have allowed me to figure out where the issue existed a lot faster and easier. (And it turned out it was the Windows' issue.) Kazuya