From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id 5F3B13858D28 for ; Tue, 14 Dec 2021 07:40:38 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 5F3B13858D28 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-480-JL3sVZ4dNYeiW6hGKW68AQ-1; Tue, 14 Dec 2021 02:40:35 -0500 X-MC-Unique: JL3sVZ4dNYeiW6hGKW68AQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id F41DE1023F4E; Tue, 14 Dec 2021 07:40:33 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.2.17.223]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B6F6F7A238; Tue, 14 Dec 2021 07:40:32 +0000 (UTC) From: Florian Weimer To: "H.J. Lu via Libc-alpha" Subject: Re: [PATCH] elf: Align argument of __munmap to page size [BZ #28676] References: <20211213152057.151438-1-hjl.tools@gmail.com> <3e6b30a4-cf8a-49c9-7382-3f3255c8201a@linux.alibaba.com> Date: Tue, 14 Dec 2021 08:40:29 +0100 In-Reply-To: (H. J. Lu via Libc-alpha's message of "Mon, 13 Dec 2021 19:34:45 -0800") Message-ID: <87y24nskgi.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-6.5 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 Dec 2021 07:40:40 -0000 * H. J. Lu via Libc-alpha: > On Mon, Dec 13, 2021 at 6:49 PM Rongwei Wang > wrote: >> >> Hi, HJ >> >> Thanks for your help to fix this bug. And I just found out that the >> patch "elf: Properly align PT_LOAD segments" had been merged into >> glibc/master. >> >> And I saw Florian's email: >> >> > We should check munmap failure though and rollback everything if >> > necessary. It's possible we can undo the initial PROT_NONE mapping even >> > if future munmap calls fail because unmapping the first mapping does not >> > need to split a mapping. >> >> It seems rollback initial PROT_NONE mapping when munmap fails is good >> idea. Nice to have. Of course, IMO, this your patch is also can fix this >> munmap failure well. what do you think? >> >> When this fix is stable in glibc upstream, I will backport it into our >> internal glibc repo. So, if you have any improve this fix suggestions, I >> will respond immediately. Sorry for my speed is much slower than your. >> >> > > Let's wait for a few days. Can we please fix the regression in some way? It impacts development, particularly at this late stage during the 2.34 cycle. Either revert the change, or at least add the unchecked __munmap, and fix that later. Thanks, Florian