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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 60102C433DF for ; Mon, 22 Jun 2020 08:20:35 +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 3085C206FA for ; Mon, 22 Jun 2020 08:20:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Jm4EIcve" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3085C206FA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:55402 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jnHgw-0007Lp-FL for qemu-devel@archiver.kernel.org; Mon, 22 Jun 2020 04:20:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60150) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jnHg4-0006MD-PD for qemu-devel@nongnu.org; Mon, 22 Jun 2020 04:19:40 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:21145 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jnHg3-0007MS-1e for qemu-devel@nongnu.org; Mon, 22 Jun 2020 04:19:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592813977; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=HBfNkhiLZwq94RrXGsptsFaKNi0i8m86p0ud9sgUBVs=; b=Jm4EIcves7zclHMDybar5+moYW6yNgp7FsqJ/fB2j4L9w8Eyrer0RBPU9O+NDOHUa1Idkf eoNJknDxASadnqMrLGJq4yV52dFB/AIZuRExmC/fIDleFLvWaPVl8M71fRKDkcQs85XWSR sRIImLIQYzTGd+Yocong+T5NqtUNMOc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-192-DcRYl1tBMwCgPksz9tb6Yg-1; Mon, 22 Jun 2020 04:19:35 -0400 X-MC-Unique: DcRYl1tBMwCgPksz9tb6Yg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B2ABE107ACCA; Mon, 22 Jun 2020 08:19:34 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-112-121.ams2.redhat.com [10.36.112.121]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6BCFD5D9DD; Mon, 22 Jun 2020 08:19:34 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 9759C113846D; Mon, 22 Jun 2020 10:19:31 +0200 (CEST) From: Markus Armbruster To: David Gibson Subject: Re: Memory leak in spapr_machine_init()? References: <874kr8uakm.fsf@dusky.pond.sub.org> <20200619041334.GI17085@umbus.fritz.box> Date: Mon, 22 Jun 2020 10:19:31 +0200 In-Reply-To: <20200619041334.GI17085@umbus.fritz.box> (David Gibson's message of "Fri, 19 Jun 2020 14:13:34 +1000") Message-ID: <87ftanpl64.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain Received-SPF: pass client-ip=205.139.110.61; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/22 03:17:49 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action 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: David Gibson , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" David Gibson writes: > On Thu, Jun 18, 2020 at 08:55:53AM +0200, Markus Armbruster wrote: >> Either I'm confused (quite possible), or kvmppc_check_papr_resize_hpt() >> can leak an Error object on failure. Please walk through the code with >> me: >> >> kvmppc_check_papr_resize_hpt(&resize_hpt_err); >> >> This sets @resize_hpt_err on failure. >> >> if (spapr->resize_hpt == SPAPR_RESIZE_HPT_DEFAULT) { >> /* >> * If the user explicitly requested a mode we should either >> * supply it, or fail completely (which we do below). But if >> * it's not set explicitly, we reset our mode to something >> * that works >> */ >> if (resize_hpt_err) { >> spapr->resize_hpt = SPAPR_RESIZE_HPT_DISABLED; >> error_free(resize_hpt_err); >> resize_hpt_err = NULL; >> >> Case 1: failure and SPAPR_RESIZE_HPT_DEFAULT; we free @resize_hpt_err. >> Good. >> >> } else { >> spapr->resize_hpt = smc->resize_hpt_default; >> } >> } >> >> assert(spapr->resize_hpt != SPAPR_RESIZE_HPT_DEFAULT); >> >> if ((spapr->resize_hpt != SPAPR_RESIZE_HPT_DISABLED) && resize_hpt_err) { >> /* >> * User requested HPT resize, but this host can't supply it. Bail out >> */ >> error_report_err(resize_hpt_err); >> exit(1); >> >> Case 2: failure and not SPAPR_RESIZE_HPT_DISABLED; fatal. Good. >> >> } >> >> What about case 3: failure and SPAPR_RESIZE_HPT_DISABLED? >> >> Good if we get here via case 1 (we freed @resize_hpt_err). >> >> Else, ??? > > I think you're right, and we leak it in this case - I think I forgot > that in the DISABLED case we still (unnecessarily) ask the kernel if > it can do it. > > Of course, it will only happen once per run, so it's not like it's a > particularly noticeable leak. Understood. I'll post a patch. Thanks!