From nobody Tue Nov 11 15:05:03 2025 Delivered-To: importer@patchew.org Received-SPF: none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=fail(p=none dis=none) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; t=1556916698; cv=none; d=zoho.com; s=zohoarc; b=UkKv1G7a6z0b07RdWKaOWQ08cDDnik8zaatWVoabMfILfnBRkBqni00O+jCq2BF3HgYxTU+9q7VichLz08iqeIASWId/2p8AIimPvErB8LZSz2Yg3hUV0DtIuyT75MXvZlgKH3voDVxU1qo5OtMTbNz1zHgKMeJ2aN6rZpsaW9A= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1556916698; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=SwMbnbGavmIEQsvvM6gxRQVHdZCepMDSUk4q6ed+3VE=; b=E5bc9lKe1yb8pPJOoMj0JaaFLGl4x7msYLgqhRjSd5MBw22PQJ/vanvjoApaV4jWNq6p5NjrloFp9fogBTdvEJEEdqfI1f5W79JVBotaKlvpXcNnIWt/HE1yzYmytn7WjD4U4mbKG7oWlWFOuQGA5uJt1nXRgCqUBPDIS7DdBXI= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=fail; spf=none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1556916698990770.1309305600205; Fri, 3 May 2019 13:51:38 -0700 (PDT) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hMf8P-0006Wi-3m; Fri, 03 May 2019 20:50:21 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hMf8O-0006WL-4b for xen-devel@lists.xenproject.org; Fri, 03 May 2019 20:50:20 +0000 Received: from mail.kernel.org (unknown [198.145.29.99]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 0e697570-6de5-11e9-828d-2b50afc410d5; Fri, 03 May 2019 20:50:17 +0000 (UTC) Received: from sstabellini-ThinkPad-X260.xilinx.com (c-67-164-102-47.hsd1.ca.comcast.net [67.164.102.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5DC9F20B7C; Fri, 3 May 2019 20:50:16 +0000 (UTC) X-Inumbo-ID: 0e697570-6de5-11e9-828d-2b50afc410d5 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556916616; bh=3IWWvsDOnuB69RLJ4DGWqOAGTi/kmS2DUY2cbb7ugjk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bs2xjMaCmhrW+IPJYUQ/o2oSd5r9ntKu7RqgAdvXBS2VF0Az87/ZLRvyJIEOR9ztd wjgvWeVnsof8TGFBPdOR0OQgBkB19CFy5Vwd8iwSWVwqUTXyCBWrq6rtJMYXHjwcL6 Zu0h4AbGvDcFmcVmvVsJyFKvoGf4gSCVWITfHr2s= From: Stefano Stabellini To: julien.grall@arm.com Date: Fri, 3 May 2019 13:50:14 -0700 Message-Id: <1556916614-21512-3-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: Subject: [Xen-devel] [PATCH 3/3] xen/arm: fix mask calculation in init_pdx 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: xen-devel@lists.xenproject.org, sstabellini@kernel.org, JBeulich@suse.com, Stefano Stabellini MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) The mask calculation in init_pdx is wrong when the first bank starts at address 0x0. The reason is that pdx_init_mask will do '0 - 1' causing an underflow. As a result, the mask becomes 0xffffffffffffffff which is the biggest possible mask and ends up causing a significant memory waste in the frametable size computation. For instance, on platforms that have a low memory bank and a high memory bank, the frametable will end up covering all the holes in between. The purpose of the mask is to be passed as a parameter to pfn_pdx_hole_setup, which based on the mask parameter caculates pfn_pdx_hole_shift, pfn_pdx_bottom_mask, etc. which are actually the important masks for frametable initialization later on. pfn_pdx_hole_setup never compresses addresses below MAX_ORDER bits (1GB on ARM). Thus, it is safe to initialize mask passing 1ULL << (MAX_ORDER + PAGE_SHIFT) as start address to pdx_init_mask. Signed-off-by: Stefano Stabellini CC: JBeulich@suse.com --- xen/arch/arm/setup.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c index ccb0f18..22f20bb 100644 --- a/xen/arch/arm/setup.c +++ b/xen/arch/arm/setup.c @@ -481,10 +481,15 @@ static paddr_t __init next_module(paddr_t s, paddr_t = *end) static void __init init_pdx(void) { paddr_t bank_start, bank_size, bank_end; - - u64 mask =3D pdx_init_mask(bootinfo.mem.bank[0].start); + u64 mask; int bank; =20 + /* + * We always map the first 1<