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 ESMTP id 8A8AF3857836 for ; Wed, 30 Jun 2021 15:38:56 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 8A8AF3857836 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-98-f0i0izyvMdmuVR6VOUfIgg-1; Wed, 30 Jun 2021 11:38:52 -0400 X-MC-Unique: f0i0izyvMdmuVR6VOUfIgg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 06B2918414B4; Wed, 30 Jun 2021 15:38:51 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-115-5.ams2.redhat.com [10.36.115.5]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2EAAF1F6; Wed, 30 Jun 2021 15:38:48 +0000 (UTC) From: Florian Weimer To: "Enrico Weigelt, metux IT consult" Cc: Thiago Macieira , hjl.tools@gmail.com, libc-alpha@sourceware.org, linux-api@vger.kernel.org, linux-arch@vger.kernel.org, x86@kernel.org Subject: Re: x86 CPU features detection for applications (and AMX) References: <22261946.eFiGugXE7Z@tjmaciei-mobl1> <3c5c29e2-1b52-3576-eda2-018fb1e58ff9@metux.net> <2379132.fg5cGID6mU@tjmaciei-mobl1> <87pmw3ifpv.fsf@oldenburg.str.redhat.com> <030f1462-2bf9-39bc-d620-6d9fbe454a27@metux.net> Date: Wed, 30 Jun 2021 17:38:47 +0200 In-Reply-To: <030f1462-2bf9-39bc-d620-6d9fbe454a27@metux.net> (Enrico Weigelt's message of "Wed, 30 Jun 2021 17:16:06 +0200") Message-ID: <87lf6ricqg.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Spam-Status: No, score=-6.7 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_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) 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: Wed, 30 Jun 2021 15:38:58 -0000 * Enrico Weigelt: > On 30.06.21 16:34, Florian Weimer wrote: > >> It breaks integration with system-wide settings, such as user/group >> databases, host name lookup, and cryptographic policies. In many >> environments, that is not really an option. > > Not necessarily, these can still be applied (and fairly simple). > You actually have to twist more extra knobs if to wanted those weird > things to happen. Sorry, this is just not true. You cannot load system libraries such as NSS modules or cryptographic libraries with a custom glibc because the system glibc could be newer, and glibc does not provide that kind of compatibility (only the other way round). Thanks, Florian