Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932674AbbHJSqn (ORCPT ); Mon, 10 Aug 2015 14:46:43 -0400 Received: from smtp.citrix.com ([66.165.176.89]:18997 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932311AbbHJSqj (ORCPT ); Mon, 10 Aug 2015 14:46:39 -0400 X-IronPort-AV: E=Sophos;i="5.15,647,1432598400"; d="scan'208";a="289765686" Date: Mon, 10 Aug 2015 19:46:37 +0100 From: Wei Liu To: Julien Grall CC: , , "Konrad Rzeszutek Wilk" , Boris Ostrovsky , David Vrabel , Wei Liu Subject: Re: [PATCH] xen/xenbus: Don't leak memory when unmapping the ring on HVM backend Message-ID: <20150810184637.GA32679@zion.uk.xensource.com> References: <1439230238-6413-1-git-send-email-julien.grall@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <1439230238-6413-1-git-send-email-julien.grall@citrix.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-DLP: MIA1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1823 Lines: 48 On Mon, Aug 10, 2015 at 07:10:38PM +0100, Julien Grall wrote: > The commit ccc9d90a9a8b5c4ad7e9708ec41f75ff9e98d61d "xenbus_client: > Extend interface to support multi-page ring" removes the call to > free_xenballooned_pages in xenbus_unmap_ring_vfree_hvm. > > This will result to not give back the pages to Linux and loose them > forever. It only happens when the backends are running in HVM domains. > > Signed-off-by: Julien Grall > > --- > Cc: Konrad Rzeszutek Wilk > Cc: Boris Ostrovsky > Cc: David Vrabel > Cc: Wei Liu > Reviewed-by: Wei Liu > Appeared in Linux 4.1. HVM backend, which is always the case on ARM, will > leak every mapped ring (i.e ~12KB per domain with 1 disk and 1 vif). > --- > drivers/xen/xenbus/xenbus_client.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c > index 9ad3272..e303535 100644 > --- a/drivers/xen/xenbus/xenbus_client.c > +++ b/drivers/xen/xenbus/xenbus_client.c > @@ -814,8 +814,10 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr) > > rv = xenbus_unmap_ring(dev, node->handles, node->nr_handles, > addrs); > - if (!rv) > + if (!rv) { > vunmap(vaddr); > + free_xenballooned_pages(node->nr_handles, node->hvm.pages); > + } > else > WARN(1, "Leaking %p, size %u page(s)\n", vaddr, > node->nr_handles); > -- > 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/