From patchwork Fri Aug 26 14:11:30 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Henrique Barboza X-Patchwork-Id: 12956062 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 44B04ECAAA3 for ; Fri, 26 Aug 2022 14:18:49 +0000 (UTC) Received: from localhost ([::1]:45214 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oRaAa-0007p0-1U for qemu-devel@archiver.kernel.org; Fri, 26 Aug 2022 10:18:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:57176) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oRa43-0007Xl-5A; Fri, 26 Aug 2022 10:12:03 -0400 Received: from mail-oi1-x235.google.com ([2607:f8b0:4864:20::235]:34527) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1oRa41-0003ot-I0; Fri, 26 Aug 2022 10:12:02 -0400 Received: by mail-oi1-x235.google.com with SMTP id r10so2137821oie.1; Fri, 26 Aug 2022 07:12:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc; bh=7nsBpd6U2T94rIp6E9694uNRx1OUw5ceVkhMbv8n9sQ=; b=dHu8iCKsKPB1tufnPw6xfyTL2kEBCGfGhu3tJziTp3HoUR7yAWchSuqbUwotSIisWs NCF/NUNgVCcEYBd+/sYghKYzdxOTHwcUsj7sCwuCVMbj0FCxZVEHMZ16/pDVLPPhSWIA 6mbGZkbE7i15GQulFK0w84gEFXYL1YqM0tl38nkZLmtNnQoeZKTue35n3RugJ2lfwPYf 5iYlINiA0drmTa2IngkPo7ZIoB7anQpBDwIa0iV7/AI5RJ2lRRaZuRoD7RwrB6GfEyTk BC7ohDXI1SciwS888L+KFrGGX+RV24DqQVEA49/k0yGtGIyHd0Aw61PIo4F0U0XfYS7j Q68w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc; bh=7nsBpd6U2T94rIp6E9694uNRx1OUw5ceVkhMbv8n9sQ=; b=LgFXJ4QougSPSFfv1DmOlIBzzqJ8fP7I/QtLvocYvhwyvsTt8W7B3bhiR3kzS3DDdv WKTuw/vdUFUDXr/yg6xF1Dwnl5ge0VmCQmU110kwlfsY5WbfDuUbIEPfLZU5j5ilBTa4 Pfvv+axFfcVUEHHCPu7zmX65HTmLkj2hgPi4HqUoL+iF0uTLy5rSFYzTY5qqqVHBdPfl IEnhfWX+1sv7V7uw9KsgqoSCcus/Gh1oIk2t1gN8E3VsSIkVS/SOUIDF5+l96BCI8W5K niNrTpK22PCrs9AV7e8MeKAtXytOpI6XOtsXq5kE/Y5U75f3EWRUqKh5AZp3WO7WoFeq wBWw== X-Gm-Message-State: ACgBeo3TZhrJ/u6Q0wuW/PCvMEssrG8vGNDzvgztlm53XFFmyETkM6lP A5pNO+30sURxitOdAkJmx7Pi4cfwpqs= X-Google-Smtp-Source: AA6agR6qmUresxANBlhkZ2M/Tqj7I4qzlcyVjp17rEp+qhM2MU1S7w7HxgCwW2B6oB3KuPfy7nZRxw== X-Received: by 2002:a54:4598:0:b0:344:e71e:3a13 with SMTP id z24-20020a544598000000b00344e71e3a13mr1760681oib.239.1661523119049; Fri, 26 Aug 2022 07:11:59 -0700 (PDT) Received: from balboa.COMFAST ([177.189.45.98]) by smtp.gmail.com with ESMTPSA id z12-20020a056808064c00b00344aa3f17d9sm1087736oih.10.2022.08.26.07.11.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Aug 2022 07:11:58 -0700 (PDT) From: Daniel Henrique Barboza To: qemu-devel@nongnu.org Cc: qemu-ppc@nongnu.org, clg@kaod.org, david@gibson.dropbear.id.au, alistair.francis@wdc.com, Daniel Henrique Barboza , Peter Maydell , qemu-arm@nongnu.org Subject: [PATCH for-7.2 v4 01/21] hw/arm: do not free machine->fdt in arm_load_dtb() Date: Fri, 26 Aug 2022 11:11:30 -0300 Message-Id: <20220826141150.7201-2-danielhb413@gmail.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220826141150.7201-1-danielhb413@gmail.com> References: <20220826141150.7201-1-danielhb413@gmail.com> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::235; envelope-from=danielhb413@gmail.com; helo=mail-oi1-x235.google.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" At this moment, arm_load_dtb() can free machine->fdt when binfo->dtb_filename is NULL. If there's no 'dtb_filename', 'fdt' will be retrieved by binfo->get_dtb(). If get_dtb() returns machine->fdt, as is the case of machvirt_dtb() from hw/arm/virt.c, fdt now has a pointer to machine->fdt. And, in that case, the existing g_free(fdt) at the end of arm_load_dtb() will make machine->fdt point to an invalid memory region. This is not an issue right now because there's no code that access machine->fdt after arm_load_dtb(), but we're going to add a couple do FDT HMP commands that will rely on machine->fdt being valid. Instead of freeing 'fdt' at the end of arm_load_dtb(), assign it to machine->fdt. This will allow the FDT of ARM machines that relies on arm_load_dtb() to be accessed later on. Since all ARM machines allocates the FDT only once, we don't need to worry about leaking the existing FDT during a machine reset (which is something that other machines have to look after, e.g. the ppc64 pSeries machine). Cc: Peter Maydell Cc: qemu-arm@nongnu.org Signed-off-by: Daniel Henrique Barboza --- hw/arm/boot.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/hw/arm/boot.c b/hw/arm/boot.c index ada2717f76..669a978157 100644 --- a/hw/arm/boot.c +++ b/hw/arm/boot.c @@ -684,7 +684,11 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo, */ rom_add_blob_fixed_as("dtb", fdt, size, addr, as); - g_free(fdt); + /* + * Update the ms->fdt pointer to enable support for + * 'dumpdtb' and 'info fdt' QMP/HMP commands. + */ + ms->fdt = fdt; return size;