From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59641) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZKStU-0004sj-PY for qemu-devel@nongnu.org; Wed, 29 Jul 2015 11:03:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZKStP-0000l5-NI for qemu-devel@nongnu.org; Wed, 29 Jul 2015 11:03:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59110) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZKStP-0000kM-Id for qemu-devel@nongnu.org; Wed, 29 Jul 2015 11:03:39 -0400 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (Postfix) with ESMTPS id 2737F90245 for ; Wed, 29 Jul 2015 15:03:39 +0000 (UTC) Date: Wed, 29 Jul 2015 18:03:36 +0300 From: "Michael S. Tsirkin" Message-ID: <20150729180313-mutt-send-email-mst@redhat.com> References: <1438170589-139333-1-git-send-email-imammedo@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1438170589-139333-1-git-send-email-imammedo@redhat.com> Subject: Re: [Qemu-devel] [PATCH for-2.4 v2 0/2] vhost: check if vhost has capacity for hotplugged memory List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Mammedov Cc: pbonzini@redhat.com, qemu-devel@nongnu.org On Wed, Jul 29, 2015 at 01:49:47PM +0200, Igor Mammedov wrote: > v1->v2: > * replace probbing with checking for > /sys/module/vhost/parameters/max_mem_regions and > if it's missing has non wrong value return > hardcoded legacy limit (64 slots). > > it's defensive patchset which helps to avoid QEMU crashing > at memory hotplug time by checking that vhost has free capacity > for an additional memory slot. What if vhost is added after memory hotplug? Don't you need to check that as well? > > Igor Mammedov (2): > vhost: add vhost_has_free_slot() interface > pc-dimm: add vhost slots limit check before commiting to hotplug > > hw/mem/pc-dimm.c | 7 +++++++ > hw/virtio/vhost-backend.c | 21 ++++++++++++++++++++- > hw/virtio/vhost-user.c | 8 +++++++- > hw/virtio/vhost.c | 21 +++++++++++++++++++++ > include/hw/virtio/vhost-backend.h | 2 ++ > include/hw/virtio/vhost.h | 1 + > stubs/Makefile.objs | 1 + > stubs/vhost.c | 6 ++++++ > 8 files changed, 65 insertions(+), 2 deletions(-) > create mode 100644 stubs/vhost.c > > -- > 1.8.3.1