From patchwork Wed Sep 26 21:28:14 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Snow X-Patchwork-Id: 10616911 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6C6F3180E for ; Wed, 26 Sep 2018 21:29:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5E06F2A5B6 for ; Wed, 26 Sep 2018 21:29:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5250D2B7AF; Wed, 26 Sep 2018 21:29:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 345752A5B6 for ; Wed, 26 Sep 2018 21:29:11 +0000 (UTC) Received: from localhost ([::1]:60735 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g5HMs-0004fD-1A for patchwork-qemu-devel@patchwork.kernel.org; Wed, 26 Sep 2018 17:29:10 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43918) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g5HMF-0004JB-2Q for qemu-devel@nongnu.org; Wed, 26 Sep 2018 17:28:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g5HME-00010y-Eb for qemu-devel@nongnu.org; Wed, 26 Sep 2018 17:28:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34010) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g5HM8-0000sk-GA; Wed, 26 Sep 2018 17:28:24 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 112CA4E919; Wed, 26 Sep 2018 21:28:21 +0000 (UTC) Received: from probe.bos.redhat.com (dhcp-17-171.bos.redhat.com [10.18.17.171]) by smtp.corp.redhat.com (Postfix) with ESMTP id E6C7560BE1; Wed, 26 Sep 2018 21:28:14 +0000 (UTC) From: John Snow To: qemu-devel@nongnu.org, qemu-block@nongnu.org Date: Wed, 26 Sep 2018 17:28:14 -0400 Message-Id: <20180926212814.3822-1-jsnow@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Wed, 26 Sep 2018 21:28:21 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH] util/hbitmaps: recalculate count on merge 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: Fam Zheng , John Snow , vsementsov@virtuozzo.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP We have been neglecting to do so, which results in wrong counts after merge. In the worst case, we may think the bitmap is empty when it has had new writes merged into it. Reported-by: Eric Blake Signed-off-by: John Snow --- util/hbitmap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/util/hbitmap.c b/util/hbitmap.c index d5aca5159f..28e9c523ab 100644 --- a/util/hbitmap.c +++ b/util/hbitmap.c @@ -759,6 +759,9 @@ bool hbitmap_merge(const HBitmap *a, const HBitmap *b, HBitmap *result) } } + /* Recompute the dirty count */ + a->count = hb_count_between(a, 0, a->size - 1); + return true; }