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 88CE6C3F6B0 for ; Tue, 9 Aug 2022 12:22:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241261AbiHIMWC (ORCPT ); Tue, 9 Aug 2022 08:22:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57154 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232784AbiHIMWB (ORCPT ); Tue, 9 Aug 2022 08:22:01 -0400 Received: from mail.efficios.com (mail.efficios.com [167.114.26.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC04B1F637; Tue, 9 Aug 2022 05:21:56 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 88CEC4290E7; Tue, 9 Aug 2022 08:21:55 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id VA4D7GnKn4e5; Tue, 9 Aug 2022 08:21:55 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id EAB714290E4; Tue, 9 Aug 2022 08:21:54 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com EAB714290E4 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efficios.com; s=default; t=1660047715; bh=yaql+OHmxrSRIFF3ySv247yWXrCOS5bC0G5bebaliwY=; h=Date:From:To:Message-ID:MIME-Version; b=Cn+kTKgqSdyG27J2H72mf4t7c15Au8g0GzhEvNz82ew6t2XB62VW85zMC0MY4dO66 bfWxHqgEmSuz2N6fGJxDi2PCxm7zQ5tOxLQrFdbKtfvJgay3+exr5GJPIFoUx4dOUF Hs9bv613auRXhX3OOMEIXadBZwbe49mmmU+Z1TGwpUovxvzTXVkI5AspHT2sRMNDeh O/Ci0Tn7PSSp5/XAVWk+uhuhg8zJC/E+H3BnLIGYP4Z5OxJMvrh79dKHY4pwvmh+FM BPordgJZ9kuWcQ8vRQFX8V6e9EhLgvzLLHWlgKZGhLyvkmnZp93GdAZKn0UfcJdh7x xlWuUUYH2AY0Q== X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id GOweDkJi16HZ; Tue, 9 Aug 2022 08:21:54 -0400 (EDT) Received: from mail03.efficios.com (mail03.efficios.com [167.114.26.124]) by mail.efficios.com (Postfix) with ESMTP id D8B874291F7; Tue, 9 Aug 2022 08:21:54 -0400 (EDT) Date: Tue, 9 Aug 2022 08:21:54 -0400 (EDT) From: Mathieu Desnoyers To: Gavin Shan Cc: Florian Weimer , 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 , andrew jones , seanjc@google.com, yihyu@redhat.com, shan gavin Message-ID: <797306043.114963.1660047714774.JavaMail.zimbra@efficios.com> In-Reply-To: <616d4de6-81f6-9d14-4e57-4a79fec45690@redhat.com> 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> <87o7wtnay6.fsf@oldenburg.str.redhat.com> <616d4de6-81f6-9d14-4e57-4a79fec45690@redhat.com> Subject: Re: [PATCH 1/2] KVM: selftests: Make rseq compatible with glibc-2.35 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [167.114.26.124] X-Mailer: Zimbra 8.8.15_GA_4304 (zclient/8.8.15_GA_4304) Thread-Topic: selftests: Make rseq compatible with glibc-2.35 Thread-Index: oHLHOFY5Vh2uVE5+gR7UtW52F8t44g== Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org ----- Gavin Shan wrote: > Hi Florian, > > On 8/9/22 5:16 PM, Florian Weimer wrote: > >>> __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). > > > > For kvm/selftests, there are 3 architectures involved actually. So we > just need consider 4 cases: aarch64, x86, s390 and other. For other > case, we just use __builtin_thread_pointer() to maintain code's > integrity, but it's not called at all. > > I think kvm/selftest is always relying on glibc if I'm correct. All those are handled in the rseq selftests and in librseq. Why duplicate all that logic again? Thanks, Mathieu > > Thanks, > Gavin > -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com