From nobody Mon Feb 9 19:52:20 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1495128557324768.4580227906321; Thu, 18 May 2017 10:29:17 -0700 (PDT) Received: from localhost ([::1]:54920 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dBPEh-0003Jj-O7 for importer@patchew.org; Thu, 18 May 2017 13:29:15 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57054) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dBPAf-0008K0-0R for qemu-devel@nongnu.org; Thu, 18 May 2017 13:25:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dBPAb-0006Sw-K9 for qemu-devel@nongnu.org; Thu, 18 May 2017 13:25:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43912) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dBPAb-0006Sc-DV for qemu-devel@nongnu.org; Thu, 18 May 2017 13:25:01 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6DD8C80486 for ; Thu, 18 May 2017 17:25:00 +0000 (UTC) Received: from secure.mitica (ovpn-117-10.ams2.redhat.com [10.36.117.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1F5E45DD70; Thu, 18 May 2017 17:24:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 6DD8C80486 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=quintela@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 6DD8C80486 From: Juan Quintela To: qemu-devel@nongnu.org Date: Thu, 18 May 2017 19:24:45 +0200 Message-Id: <20170518172453.32599-2-quintela@redhat.com> In-Reply-To: <20170518172453.32599-1-quintela@redhat.com> References: <20170518172453.32599-1-quintela@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 18 May 2017 17:25:00 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 01/18] migration: Fix non-multiple of page size migration X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: lvivier@redhat.com, dgilbert@redhat.com, peterx@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: "Dr. David Alan Gilbert" Unfortunately it's legal to create a VM with a RAM size that's not a multiple of the underlying host page or huge page size. Recently I'd changed things to always send host sized pages, and that breaks if we have say a 1025MB guest on 2MB hugepages. Unfortunately we can't just make that illegal since it would break migration from/to existing oddly configured VMs. Symptom: qemu-system-x86_64: Illegal RAM offset 40100000 as it transmits the fraction of the hugepage after the end of the RAMBlock (may also cause a crash on the source - possibly due to clearing bits after the bitmap) Reported-by: Yumei Huang Red Hat bug: https://bugzilla.redhat.com/show_bug.cgi?id=3D1449037 Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela --- migration/ram.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/migration/ram.c b/migration/ram.c index f59fdd4..59459ef 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1312,6 +1312,8 @@ static int ram_save_target_page(RAMState *rs, PageSea= rchStatus *pss, * a host page in which case the remainder of the hostpage is sent. * Only dirty target pages are sent. Note that the host page size may * be a huge page for this block. + * The saving stops at the boundary of the used_length of the block + * if the RAMBlock isn't a multiple of the host page size. * * Returns the number of pages written or negative on error * @@ -1335,7 +1337,8 @@ static int ram_save_host_page(RAMState *rs, PageSearc= hStatus *pss, =20 pages +=3D tmppages; pss->page++; - } while (pss->page & (pagesize_bits - 1)); + } while ((pss->page & (pagesize_bits - 1)) && + offset_in_ramblock(pss->block, pss->page << TARGET_PAGE_BITS)= ); =20 /* The offset we leave with is the last one we looked at */ pss->page--; --=20 2.9.3