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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 D8836C433DB for ; Mon, 15 Mar 2021 13:36:34 +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 6330D60240 for ; Mon, 15 Mar 2021 13:36:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6330D60240 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bugs.launchpad.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45654 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lLnOb-0003xD-Hq for qemu-devel@archiver.kernel.org; Mon, 15 Mar 2021 09:36:33 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39464) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lLnNi-00031I-U5 for qemu-devel@nongnu.org; Mon, 15 Mar 2021 09:35:38 -0400 Received: from indium.canonical.com ([91.189.90.7]:43082) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1lLnNh-0000Ms-0n for qemu-devel@nongnu.org; Mon, 15 Mar 2021 09:35:38 -0400 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.86_2 #2 (Debian)) id 1lLnNf-0006Lm-7y for ; Mon, 15 Mar 2021 13:35:35 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id 225712E815F for ; Mon, 15 Mar 2021 13:35:35 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Date: Mon, 15 Mar 2021 13:28:26 -0000 From: Peter Maydell <1918302@bugs.launchpad.net> To: qemu-devel@nongnu.org X-Launchpad-Notification-Type: bug X-Launchpad-Bug: product=qemu; status=In Progress; importance=Undecided; assignee=alex.bennee@linaro.org; X-Launchpad-Bug-Tags: arm semihosting X-Launchpad-Bug-Information-Type: Public X-Launchpad-Bug-Private: no X-Launchpad-Bug-Security-Vulnerability: no X-Launchpad-Bug-Commenters: ajbennee pmaydell statham-arm X-Launchpad-Bug-Reporter: Simon Tatham (statham-arm) X-Launchpad-Bug-Modifier: Peter Maydell (pmaydell) References: <161530383644.26074.10419563158373925479.malonedeb@gac.canonical.com> Message-Id: <161581490613.17173.11512699561363337781.malone@wampee.canonical.com> Subject: [Bug 1918302] Re: qemu-system-arm segfaults while servicing SYS_HEAPINFO X-Launchpad-Message-Rationale: Subscriber (QEMU) @qemu-devel-ml X-Launchpad-Message-For: qemu-devel-ml Precedence: bulk X-Generated-By: Launchpad (canonical.com); Revision="d4fcb062545ed29d3cd7773e52e43615e042623f"; Instance="production" X-Launchpad-Hash: 6df973ec143f7d8a9644f6e9afb9676c610838db Received-SPF: none client-ip=91.189.90.7; envelope-from=bounces@canonical.com; helo=indium.canonical.com X-Spam_score_int: -65 X-Spam_score: -6.6 X-Spam_bar: ------ X-Spam_report: (-6.6 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, RCVD_IN_DNSWL_HI=-5, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Bug 1918302 <1918302@bugs.launchpad.net> Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Looking at the current stack seems an odd approach, because often semihosting guest programs use HEAPINFO to find out what they should set SP to in the first place... -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1918302 Title: qemu-system-arm segfaults while servicing SYS_HEAPINFO Status in QEMU: In Progress Bug description: I compiled QEMU version 5.2.0 from source on Ubuntu 18.04, and tried to use it to run the attached bare-metal Arm hello-world image, using the command line qemu-system-arm -M microbit -semihosting -nographic -device loader,file=3Dhello.hex The result was that qemu-system-arm itself died of a segfault. Compiling it for debugging, the location of the segfault was in target/arm/arm-semi.c, in the case handler for the semihosting call TARGET_SYS_HEAPINFO, on line 1020 which assigns to 'rambase': const struct arm_boot_info *info =3D env->boot_info; target_ulong rambase =3D info->loader_start; and the problem seems to be that 'info', aka env->boot_info, is NULL in this context. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1918302/+subscriptions