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 [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id CCD1F3861881 for ; Mon, 28 Jun 2021 11:06:22 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org CCD1F3861881 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-219-pSMeRt-YMNeXQfmbw7ZAYg-1; Mon, 28 Jun 2021 07:06:19 -0400 X-MC-Unique: pSMeRt-YMNeXQfmbw7ZAYg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C27571084F58; Mon, 28 Jun 2021 11:06:17 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-112-228.ams2.redhat.com [10.36.112.228]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AA15F369A; Mon, 28 Jun 2021 11:06:16 +0000 (UTC) From: Florian Weimer To: Wilco Dijkstra Cc: Wilco Dijkstra via Libc-alpha , Szabolcs Nagy Subject: Re: [PATCH] AArch64: Add hp-timing.h References: <87pmw6uw73.fsf@oldenburg.str.redhat.com> Date: Mon, 28 Jun 2021 13:06:14 +0200 In-Reply-To: (Wilco Dijkstra's message of "Mon, 28 Jun 2021 10:53:05 +0000") Message-ID: <87h7hiuu3d.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 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain 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_PASS, 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: Mon, 28 Jun 2021 11:06:24 -0000 * Wilco Dijkstra: > Hi Florian, > >> Is the MSR called cntcvt_el0 or cntvct_el0? > > cntvct_el0 - it's just a random combination of characters! Okay, then please fix the other occurence that is a typo. >> I'm clearly missing something: If this is broken on some kernels, how is >> this disabled? > > It's not enabled just to be extremely conservative - however I don't > believe this is an issue in practice since it works fine even on the > first AArch64 boards and servers. I meant: How is this disabled in glibc on older kernels? Or is this code just dormant as of now? Thanks, Florian