From nobody Tue Nov 11 04:56:26 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1560993485; cv=none; d=zoho.com; s=zohoarc; b=jJgHwwG8zBIhUzf6CIlZ98XpUCt4oF7u5lAi5eJWRjJnfBLkQVJZaXZO/3HfS6EZvB2xYBTO5GEBWraARhKUDoXTgqSo3J45Ll6LbhQaORhIffRikvdUKBjWIwhacyX+Kg7PjYdkKbsYJqevS5U1JLQKSpS+wudOemi1D5KkJjw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1560993485; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=hGRR4tlWLI//LeUlu16/PI05Amv1NDvHQbht3PVhY7E=; b=IA6FK2nXkHyZMoDS5gobkPCNkPbtUibon36PfxphqsYFK/ZNsb5fO0anPlzBySOid/P89meoa8XeyWEE2/ZqZ+uklCF1XCMfz22YFTygmWEpUEMauGDm8aN2ArjmcF9Bw2WXCYZAtE+KYFyjez9JAAYMgMCS6FQpKA0S4/ayWVg= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1560993485831929.7018017951995; Wed, 19 Jun 2019 18:18:05 -0700 (PDT) Received: from localhost ([::1]:42890 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hdliE-0004qd-Kv for importer@patchew.org; Wed, 19 Jun 2019 21:18:02 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40708) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hdle7-0002EK-L9 for qemu-devel@nongnu.org; Wed, 19 Jun 2019 21:13:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hdlUo-0004pQ-Pi for qemu-devel@nongnu.org; Wed, 19 Jun 2019 21:04:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54584) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hdlUn-0004mk-40; Wed, 19 Jun 2019 21:04:09 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 55F4381129; Thu, 20 Jun 2019 01:04:08 +0000 (UTC) Received: from probe.bos.redhat.com (dhcp-17-164.bos.redhat.com [10.18.17.164]) by smtp.corp.redhat.com (Postfix) with ESMTP id 395671001E67; Thu, 20 Jun 2019 01:04:07 +0000 (UTC) From: John Snow To: qemu-devel@nongnu.org, qemu-block@nongnu.org Date: Wed, 19 Jun 2019 21:03:48 -0400 Message-Id: <20190620010356.19164-5-jsnow@redhat.com> In-Reply-To: <20190620010356.19164-1-jsnow@redhat.com> References: <20190620010356.19164-1-jsnow@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 20 Jun 2019 01:04:08 +0000 (UTC) Content-Transfer-Encoding: quoted-printable 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 04/12] hbitmap: Fix merge when b is empty, and result is not an alias of a X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Fam Zheng , vsementsov@virtuozzo.com, Wen Congyang , Xie Changlong , Markus Armbruster , Max Reitz , John Snow Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" Nobody calls the function like this currently, but we neither prohibit or cope with this behavior. I decided to make the function cope with it. Signed-off-by: John Snow --- util/hbitmap.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/util/hbitmap.c b/util/hbitmap.c index 7905212a8b..45d1725daf 100644 --- a/util/hbitmap.c +++ b/util/hbitmap.c @@ -781,8 +781,9 @@ bool hbitmap_can_merge(const HBitmap *a, const HBitmap = *b) } =20 /** - * Given HBitmaps A and B, let A :=3D A (BITOR) B. - * Bitmap B will not be modified. + * Given HBitmaps A and B, let R :=3D A (BITOR) B. + * Bitmaps A and B will not be modified, + * except when bitmap R is an alias of A or B. * * @return true if the merge was successful, * false if it was not attempted. @@ -797,7 +798,9 @@ bool hbitmap_merge(const HBitmap *a, const HBitmap *b, = HBitmap *result) } assert(hbitmap_can_merge(b, result)); =20 - if (hbitmap_count(b) =3D=3D 0) { + if ((!hbitmap_count(a) && result =3D=3D b) || + (!hbitmap_count(b) && result =3D=3D a) || + (!hbitmap_count(a) && !hbitmap_count(b))) { return true; } =20 --=20 2.21.0