From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90814C433FF for ; Thu, 1 Aug 2019 01:53:41 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5F5CC20B7C for ; Thu, 1 Aug 2019 01:53:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="EnONfDgr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5F5CC20B7C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45434 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1ht0Hk-0005zi-AR for qemu-devel@archiver.kernel.org; Wed, 31 Jul 2019 21:53:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39964) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1ht0HM-0005Xz-Ki for qemu-devel@nongnu.org; Wed, 31 Jul 2019 21:53:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ht0HL-0001fx-Rl for qemu-devel@nongnu.org; Wed, 31 Jul 2019 21:53:16 -0400 Received: from mail-ed1-x542.google.com ([2a00:1450:4864:20::542]:44416) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1ht0HL-0001fB-Lq; Wed, 31 Jul 2019 21:53:15 -0400 Received: by mail-ed1-x542.google.com with SMTP id k8so67518274edr.11; Wed, 31 Jul 2019 18:53:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=kAuUUSgahp5qR1FSK0QzNmg9PlAhnc6gE73hIu7pHXA=; b=EnONfDgrNTVdzp/CqZoabbyf35bTj+OeL0Uwm7kt0jweBhmhTiett+vgp2/kqbNZtn sU5h6889N5WUiScphFcErXvAaw7LqeUKY4R9yUQfnPX3Wzw4K8bsGheI4V3WC00+Lpf8 6aHSBBFH7kgAXRda26XludXce2FnQI1/wpfMolH5Y7YgN0o7TLR/gSDpm1AWQXG37o2Z wCJ1vcHj3RWIfkqVGS0jtpau5d0/PSYHjLEOy/sf5fO5DFbeCEAsQrWo6jcPQqrzoUHF wCVZw4ysGy6zOWwZ4umw6fq9H5Ooovb9ecHVXTCUG/Zz+/rWpw946jS+3bUZujERTS45 uN6w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=kAuUUSgahp5qR1FSK0QzNmg9PlAhnc6gE73hIu7pHXA=; b=cCjiLmP4wyhjnkMOIwNNtR3REI2yyEZ0khxGJJ/keU2pWaOX8tQBTdtk1vb8Sw6Kpt FAALVyADbaMfY63WUHT/4smMs92PNiyXg5mCN0cDbjXemFQn2Orlg2vf4HzkG7N8wfr5 9Sc8a28JTn1zguI5r/smWmc0aIBuoSkrxkbDetY2gCiyAI3bZn1yOdNd7PVIWYLjXY19 cKjljYqbt3F1rKKvVUDtWc49uH8FYIsTMJ7liG0Q+kg0Suvd5FiJfQbjfUzUxEJuTpXj 3q55qHL9EI5Qx3yvRH17+BBS1v5JCfl+rGKVygN0Zseb+XbXcqhjCJxqCLxr8mjFOPXx 7Reg== X-Gm-Message-State: APjAAAUfwnPmFxhAGKRB7Ugg5rFmaf+gPAoynxsARqd9P1NFaDtoFJaZ jsHveHAlId/jDKbckMkaL5TfBotOsZZ3QcQPerM= X-Google-Smtp-Source: APXvYqzGZqCraUn3bSmXvl68EZNyVsacvzTt7i2LBYyEnkd7PPhYlBvS0n0qCq/Mjl7T4ngeM7I0hdU91wAOJ111ClU= X-Received: by 2002:a50:ad0c:: with SMTP id y12mr108423584edc.25.1564624394111; Wed, 31 Jul 2019 18:53:14 -0700 (PDT) MIME-Version: 1.0 References: <1564577101-29020-1-git-send-email-bmeng.cn@gmail.com> <581a0284-c658-265f-1b0f-6f4be5406cee@linaro.org> In-Reply-To: <581a0284-c658-265f-1b0f-6f4be5406cee@linaro.org> From: Bin Meng Date: Thu, 1 Aug 2019 09:53:03 +0800 Message-ID: To: Richard Henderson Content-Type: text/plain; charset="UTF-8" X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2a00:1450:4864:20::542 Subject: Re: [Qemu-devel] [PATCH] riscv: rv32: Root page table address can be larger than 32-bit 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: QEMU riscv , Sagar Karandikar , Bastian Koppelmann , Palmer Dabbelt , QEMU devel , Alistair Francis Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Archived-At: List-Archive: Hi Richard, On Thu, Aug 1, 2019 at 1:35 AM Richard Henderson wrote: > > On 7/31/19 5:45 AM, Bin Meng wrote: > > - target_ulong base; > > + hwaddr base; > ... > > - target_ulong pte_addr = base + idx * ptesize; > > + hwaddr pte_addr = base + idx * ptesize; > > I believe that you either need > > base + (hwaddr)idx * ptesize > > or change the type of idx to hwaddr above. > > Otherwise the multiply overflows before it gets promoted with the add. > I am not sure how (idx * ptesize) could overflow. It represents the offset by a page table which is [0, 4096). Regards, Bin