From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752246AbbCTNq4 (ORCPT ); Fri, 20 Mar 2015 09:46:56 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:24770 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751500AbbCTNqz (ORCPT ); Fri, 20 Mar 2015 09:46:55 -0400 Date: Fri, 20 Mar 2015 14:46:42 +0100 From: Daniel Kiper To: Juergen Gross Cc: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, konrad.wilk@oracle.com, david.vrabel@citrix.com, boris.ostrovsky@oracle.com, pebolle@tiscali.nl Subject: Re: [Patch V2 2/2] xen: before ballooning hotplugged memory, set frames to invalid Message-ID: <20150320134642.GJ27971@olila.local.net-space.pl> References: <1426856139-3359-1-git-send-email-jgross@suse.com> <1426856139-3359-3-git-send-email-jgross@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1426856139-3359-3-git-send-email-jgross@suse.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: userv0022.oracle.com [156.151.31.74] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 20, 2015 at 01:55:39PM +0100, Juergen Gross wrote: > Commit 25b884a83d487fd62c3de7ac1ab5549979188482 ("x86/xen: set > regions above the end of RAM as 1:1") introduced a regression. > > To be able to add memory pages which were added via memory hotplug to > a pv domain, the pages must be "invalid" instead of "identity" in the > p2m list before they can be added. > > Suggested-by: David Vrabel > Signed-off-by: Juergen Gross In general... Reviewed-by: Daniel Kiper ... but... > --- > drivers/xen/balloon.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c > index 0b52d92..65fedb8 100644 > --- a/drivers/xen/balloon.c > +++ b/drivers/xen/balloon.c > @@ -229,6 +229,19 @@ static enum bp_state reserve_additional_memory(long credit) > balloon_hotplug = round_up(balloon_hotplug, PAGES_PER_SECTION); > nid = memory_add_physaddr_to_nid(hotplug_start_paddr); > > +#ifdef CONFIG_XEN_HAVE_PVMMU > + if (!xen_feature(XENFEAT_auto_translated_physmap)) { > + unsigned long pfn, i; > + > + pfn = PFN_DOWN(hotplug_start_paddr); > + for (i = 0; i < balloon_hotplug; i++) > + if (!set_phys_to_machine(pfn + i, INVALID_P2M_ENTRY)) { > + pr_warn("set_phys_to_machine() failed, no memory added\n"); > + return BP_ECANCELED; > + } > + } > +#endif Should not we fill everything above "maxmem" with INVALID_P2M_ENTRY at boot time? Daniel