From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51652) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZDCA6-0007Cu-JO for qemu-devel@nongnu.org; Thu, 09 Jul 2015 09:46:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZDCA2-0005VH-GB for qemu-devel@nongnu.org; Thu, 09 Jul 2015 09:46:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55551) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZDCA2-0005Ur-As for qemu-devel@nongnu.org; Thu, 09 Jul 2015 09:46:46 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (Postfix) with ESMTPS id 9E4F32C76EC for ; Thu, 9 Jul 2015 13:46:45 +0000 (UTC) Date: Thu, 9 Jul 2015 16:46:43 +0300 From: "Michael S. Tsirkin" Message-ID: <20150709164336-mutt-send-email-mst@redhat.com> References: <1436442444-132020-1-git-send-email-imammedo@redhat.com> <1436442444-132020-5-git-send-email-imammedo@redhat.com> <20150709155919-mutt-send-email-mst@redhat.com> <559E7A65.6080908@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <559E7A65.6080908@redhat.com> Subject: Re: [Qemu-devel] [PATCH v4 4/7] pc: fix QEMU crashing when more than ~50 memory hotplugged List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Igor Mammedov , qemu-devel@nongnu.org On Thu, Jul 09, 2015 at 03:43:01PM +0200, Paolo Bonzini wrote: > > > On 09/07/2015 15:06, Michael S. Tsirkin wrote: > > > QEMU asserts in vhost due to hitting vhost backend limit > > > on number of supported memory regions. > > > > > > Describe all hotplugged memory as one continuos range > > > to vhost with linear 1:1 HVA->GPA mapping in backend. > > > > > > Signed-off-by: Igor Mammedov > > > > Hmm - a bunch of work here to recombine MRs that memory listener > > interface breaks up. In particular KVM could benefit from this too (on > > workloads that change the table a lot). Can't we teach memory core to > > pass hva range as a single continuous range to memory listeners? > > Memory listeners are based on memory regions, not HVA ranges. > > Paolo Many listeners care about HVA ranges. I know KVM and vhost do. I guess we could create dummy MRs to fill in the holes left by memory hotplug? vhost already has logic to recombine consequitive chunks created by memory core. -- MST