From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=41479 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q8vCP-0008KY-4w for qemu-devel@nongnu.org; Sun, 10 Apr 2011 10:01:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Q8vCO-0002ad-7O for qemu-devel@nongnu.org; Sun, 10 Apr 2011 10:01:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54851) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Q8vCN-0002aS-U1 for qemu-devel@nongnu.org; Sun, 10 Apr 2011 10:01:08 -0400 Message-ID: <4DA1B81C.8000506@redhat.com> Date: Sun, 10 Apr 2011 17:01:00 +0300 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [Qemu-devel] Re: software breakpoints disappearing/reappearing in KVM/qemu References: <4D9F7597.7020604@web.de> In-Reply-To: <4D9F7597.7020604@web.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: qemu-devel@nongnu.org, Craig Brozefsky On 04/08/2011 11:52 PM, Jan Kiszka wrote: > QEMU's gdbstub in KVM mode is simply not designed to account for guests > swapping out code pages that contain breakpoints. Due to the fact that > the Linux kernel does not do these weird things to its own code, It actually happily patches its own code at certain circumstances. If you debug early boot or suspend/resume or cpu hotplug you're likely to encounter them. > at > least I never seriously thought about potential workarounds. As your > approach indicates, those might become fairly guest-specific - if they > can be implemented reliably at all. -- error compiling committee.c: too many arguments to function