From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60789) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z0BGU-0004R6-Ok for qemu-devel@nongnu.org; Wed, 03 Jun 2015 12:11:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z0BGQ-00053A-LD for qemu-devel@nongnu.org; Wed, 03 Jun 2015 12:11:38 -0400 Received: from mail-wi0-x234.google.com ([2a00:1450:400c:c05::234]:38737) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z0BGQ-00051g-EJ for qemu-devel@nongnu.org; Wed, 03 Jun 2015 12:11:34 -0400 Received: by wibdt2 with SMTP id dt2so19065140wib.1 for ; Wed, 03 Jun 2015 09:11:33 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <556F2731.8010801@redhat.com> Date: Wed, 03 Jun 2015 18:11:29 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1433334157-37665-1-git-send-email-imammedo@redhat.com> <1433334157-37665-3-git-send-email-imammedo@redhat.com> <556EF7AE.8040609@redhat.com> <20150603160526.7727e4e4@nial.brq.redhat.com> <556F1850.7090903@redhat.com> <20150603172347.481107ae@nial.brq.redhat.com> In-Reply-To: <20150603172347.481107ae@nial.brq.redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC 2/2] pc: fix QEMU crashing when more than ~50 memory hotplugged List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Mammedov Cc: qemu-devel@nongnu.org, mst@redhat.com On 03/06/2015 17:23, Igor Mammedov wrote: >> > Understood now. This still should be a separate patch. I'm much more >> > confident with the other two (e.g. what happens if a malicious guest >> > writes to memory that is still MAP_NORESERVE), > it should get SIGSEVG due to access to PROT_NONE. QEMU doesn't get the SEGV if you do address_space_rw or address_space_map to unallocated space, because the empty area in the container is treated as MMIO. But what does vhost do if you tell it to treat the whole block as a single huge lump? Paolo >> > so feel free to post >> > those without RFC tag. But the vhost one really needs mst's eyes. > ok, I'll split it out. >