From patchwork Mon Jun 17 15:41:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anthony PERARD X-Patchwork-Id: 10999653 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 664641395 for ; Mon, 17 Jun 2019 15:42:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 55F3628969 for ; Mon, 17 Jun 2019 15:42:34 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4A4D52896F; Mon, 17 Jun 2019 15:42:34 +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=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A12AF28969 for ; Mon, 17 Jun 2019 15:42:33 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hctky-0008M6-HG; Mon, 17 Jun 2019 15:41:16 +0000 Received: from us1-rack-dfw2.inumbo.com ([104.130.134.6]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hctkw-0008LU-Va for xen-devel@lists.xenproject.org; Mon, 17 Jun 2019 15:41:15 +0000 X-Inumbo-ID: 561209d7-9116-11e9-8980-bc764e045a96 Received: from esa4.hc3370-68.iphmx.com (unknown [216.71.155.144]) by us1-rack-dfw2.inumbo.com (Halon) with ESMTPS id 561209d7-9116-11e9-8980-bc764e045a96; Mon, 17 Jun 2019 15:41:13 +0000 (UTC) Authentication-Results: esa4.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none; spf=None smtp.pra=anthony.perard@citrix.com; spf=Pass smtp.mailfrom=anthony.perard@citrix.com; spf=None smtp.helo=postmaster@mail.citrix.com Received-SPF: None (esa4.hc3370-68.iphmx.com: no sender authenticity information available from domain of anthony.perard@citrix.com) identity=pra; client-ip=162.221.158.21; receiver=esa4.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="anthony.perard@citrix.com"; x-conformance=sidf_compatible Received-SPF: Pass (esa4.hc3370-68.iphmx.com: domain of anthony.perard@citrix.com designates 162.221.158.21 as permitted sender) identity=mailfrom; client-ip=162.221.158.21; receiver=esa4.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="anthony.perard@citrix.com"; x-conformance=sidf_compatible; x-record-type="v=spf1"; x-record-text="v=spf1 ip4:209.167.231.154 ip4:178.63.86.133 ip4:195.66.111.40/30 ip4:85.115.9.32/28 ip4:199.102.83.4 ip4:192.28.146.160 ip4:192.28.146.107 ip4:216.52.6.88 ip4:216.52.6.188 ip4:162.221.158.21 ip4:162.221.156.83 ~all" Received-SPF: None (esa4.hc3370-68.iphmx.com: no sender authenticity information available from domain of postmaster@mail.citrix.com) identity=helo; client-ip=162.221.158.21; receiver=esa4.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="postmaster@mail.citrix.com"; x-conformance=sidf_compatible IronPort-SDR: m8p7QSPWyD6XAlP0UCvQs8rrSZpRFRITJnOmdhyixFTQF+HI+KTQhyUcxt3Wzbd7aww30IHafu PM5jGuamTqsXMfNgjC99ipQShn66hGYE8f+KNXYQGtgGZVaRFmHSrH+ae4Dre9+jkV9DC+LWt6 JrBm9ctvIIWM+cZRKH8V2TqzoaUlO2KVzqrzfkOrO+e/KOBKtTkpsyAQ1v0P/qHm02McQ3MEwM Nhx3hbhykEwGGG6ukfgPV9rLzbAfAVcMH5YwFtVkW2x9S/i9zwxBEBNmVfaxHfFd31t0mJLB6N 9Lc= X-SBRS: 2.7 X-MesageID: 1846122 X-Ironport-Server: esa4.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.63,385,1557201600"; d="scan'208";a="1846122" From: Anthony PERARD To: Date: Mon, 17 Jun 2019 16:41:05 +0100 Message-ID: <20190617154105.32323-5-anthony.perard@citrix.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190617154105.32323-1-anthony.perard@citrix.com> References: <20190617154105.32323-1-anthony.perard@citrix.com> MIME-Version: 1.0 Subject: [Xen-devel] [PATCH 4/4] xen: Avoid VLA X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Anthony PERARD , xen-devel@lists.xenproject.org, Stefano Stabellini , Paul Durrant Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP Avoid using a variable length array. Signed-off-by: Anthony PERARD --- Notes: Was suggested by Peter here: "should we try to stop using variable length arrays?" hw/i386/xen/xen-hvm.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/hw/i386/xen/xen-hvm.c b/hw/i386/xen/xen-hvm.c index 725f9c2278..10d73b55b4 100644 --- a/hw/i386/xen/xen-hvm.c +++ b/hw/i386/xen/xen-hvm.c @@ -615,7 +615,8 @@ static void xen_sync_dirty_bitmap(XenIOState *state, { hwaddr npages = size >> TARGET_PAGE_BITS; const int width = sizeof(unsigned long) * 8; - unsigned long bitmap[DIV_ROUND_UP(npages, width)]; + unsigned long *bitmap = NULL; + size_t bitmap_size = DIV_ROUND_UP(npages, width); int rc, i, j; const XenPhysmap *physmap = NULL; @@ -632,6 +633,8 @@ static void xen_sync_dirty_bitmap(XenIOState *state, return; } + bitmap = g_new0(unsigned long, bitmap_size); + rc = xen_track_dirty_vram(xen_domid, start_addr >> TARGET_PAGE_BITS, npages, bitmap); if (rc < 0) { @@ -644,10 +647,10 @@ static void xen_sync_dirty_bitmap(XenIOState *state, ", 0x" TARGET_FMT_plx "): %s\n", start_addr, start_addr + size, strerror(errno)); } - return; + goto out; } - for (i = 0; i < ARRAY_SIZE(bitmap); i++) { + for (i = 0; i < bitmap_size; i++) { unsigned long map = bitmap[i]; while (map != 0) { j = ctzl(map); @@ -657,6 +660,8 @@ static void xen_sync_dirty_bitmap(XenIOState *state, TARGET_PAGE_SIZE); }; } +out: + g_free(bitmap); } static void xen_log_start(MemoryListener *listener,