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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CEB7EC3F6B0 for ; Tue, 9 Aug 2022 07:16:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238723AbiHIHQn (ORCPT ); Tue, 9 Aug 2022 03:16:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44516 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238173AbiHIHQl (ORCPT ); Tue, 9 Aug 2022 03:16:41 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E9EE320BFC for ; Tue, 9 Aug 2022 00:16:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660029400; 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=pFDs6xidhpbw1qYaUFr1MfUDhoMVpVETbRmiPl3tRsM=; b=fXa1CMGcAXRVWNbH3E/l6WQrDeXMQ20xhdrLw5OvDmN+dmqEB4kG2lH6s3hGyrN2qtu01M kFD90sce6ZgEz7J5uKMS/xlqUQTsG94jHmgV5bVcwOSAL6zMnqlO++Uxo1MNdFvwgD6cWf Xq+U71d4E8kv2DHjKENTSANZMayCez8= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-607-wVvB783QNq-aMoXaZIWmxA-1; Tue, 09 Aug 2022 03:16:38 -0400 X-MC-Unique: wVvB783QNq-aMoXaZIWmxA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 37B753801FE4; Tue, 9 Aug 2022 07:16:38 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.193.65]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2DC411415125; Tue, 9 Aug 2022 07:16:35 +0000 (UTC) From: Florian Weimer To: Gavin Shan Cc: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, maz@kernel.org, oliver.upton@linux.dev, andrew.jones@linux.dev, seanjc@google.com, mathieu.desnoyers@efficios.com, yihyu@redhat.com, shan.gavin@gmail.com Subject: Re: [PATCH 1/2] KVM: selftests: Make rseq compatible with glibc-2.35 References: <20220809060627.115847-1-gshan@redhat.com> <20220809060627.115847-2-gshan@redhat.com> <8735e6ncxw.fsf@oldenburg.str.redhat.com> <7844e3fa-e49e-de75-e424-e82d3a023dd6@redhat.com> Date: Tue, 09 Aug 2022 09:16:33 +0200 In-Reply-To: <7844e3fa-e49e-de75-e424-e82d3a023dd6@redhat.com> (Gavin Shan's message of "Tue, 9 Aug 2022 18:45:26 +1000") Message-ID: <87o7wtnay6.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 2.85 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org * Gavin Shan: >> __builtin_thread_pointer doesn't work on all architectures/GCC >> versions. >> Is this a problem for selftests? >> > > It's a problem as the test case is running on all architectures. I think I > need introduce our own __builtin_thread_pointer() for where it's not > supported: (1) PowerPC (2) x86 without GCC 11 > > Please let me know if I still have missed cases where > __buitin_thread_pointer() isn't supported? As far as I know, these are the two outliers that also have rseq support. The list is a bit longer if we also consider non-rseq architectures (csky, hppa, ia64, m68k, microblaze, sparc, don't know about the Linux architectures without glibc support). Thanks, Florian