From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0202D3FC3 for ; Tue, 31 Aug 2021 15:18:46 +0000 (UTC) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 17VF4TA3052060; Tue, 31 Aug 2021 11:18:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=date : from : to : cc : subject : message-id : references : content-type : in-reply-to : mime-version; s=pp1; bh=zuHAQQs0gmUCQco7aRWvmy11cWZcfnUYpyX3TZ43UXA=; b=geLgWUQisEKJDUnurg1sfiX+fo4evxjnzjVzvbXl3ZSDW+94yPKFMECGxf6Gi5ElZh1y qejCRqU5g+ZCjZr3uOwxfpzDjjtJ6IvZQOOiYTdqG7yzkeDM3TopRK2l5RVJcxe6MA5q FQ5gnfk44T+pDTl+mL/CLJ1y7Q7gmSJWdU/D5Nks+G0Q0dkbfwnud1wV1FfGJ6QiV2AU pOXlXIEwazZCOd8Ugb2mopSZ2VvIJpFseHz3qgsuAuriVGpCS2lJc6sQjtoygk60115d ukeW9PbHTArw1RB4CTp/Wnm9jMGQhzu86Hc8k09zpbKUHgd6KwYQy0qjmUGGg7v6UGZK 7w== Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 3asp891pfj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 31 Aug 2021 11:18:38 -0400 Received: from m0098413.ppops.net (m0098413.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 17VF5hbJ064295; Tue, 31 Aug 2021 11:18:38 -0400 Received: from ppma05fra.de.ibm.com (6c.4a.5195.ip4.static.sl-reverse.com [149.81.74.108]) by mx0b-001b2d01.pphosted.com with ESMTP id 3asp891pf6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 31 Aug 2021 11:18:38 -0400 Received: from pps.filterd (ppma05fra.de.ibm.com [127.0.0.1]) by ppma05fra.de.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 17VFGxVV008705; Tue, 31 Aug 2021 15:18:36 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma05fra.de.ibm.com with ESMTP id 3aqcs8uxr0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 31 Aug 2021 15:18:36 +0000 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 17VFIWvG29032706 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 31 Aug 2021 15:18:32 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 240214208A; Tue, 31 Aug 2021 15:18:32 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BF60542087; Tue, 31 Aug 2021 15:18:31 +0000 (GMT) Received: from osiris (unknown [9.145.60.147]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Tue, 31 Aug 2021 15:18:31 +0000 (GMT) Date: Tue, 31 Aug 2021 17:18:30 +0200 From: Heiko Carstens To: Marco Elver Cc: Christian Borntraeger , Nathan Chancellor , Linus Torvalds , Vasily Gorbik , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, qemu-s390x Subject: Re: [GIT PULL] s390 updates for 5.15 merge window Message-ID: References: <82161448-2770-158c-fdd3-d253b4ae476f@de.ibm.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-TM-AS-GCONF: 00 X-Proofpoint-GUID: 7xetOQ97Ah06IA0LnvIUpM37fwGRXaQ0 X-Proofpoint-ORIG-GUID: QLg8D5EGsrGv4VqBqEToK6xy605cjhtA X-Proofpoint-UnRewURL: 0 URL was un-rewritten Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.790 definitions=2021-08-31_07:2021-08-31,2021-08-31 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 mlxscore=0 impostorscore=0 lowpriorityscore=0 malwarescore=0 suspectscore=0 priorityscore=1501 phishscore=0 bulkscore=0 spamscore=0 mlxlogscore=682 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2107140000 definitions=main-2108310080 On Tue, Aug 31, 2021 at 05:02:15PM +0200, Marco Elver wrote: > On Tue, Aug 31, 2021 at 12:46PM +0200, Marco Elver wrote: > > On Tue, 31 Aug 2021 at 12:13, Heiko Carstens wrote: > I repro'd, and the problem is part QEMU TCG and a minor problem with > stack_trace_save() on s390: > > 1. QEMU TCG doesn't seem to want to execute threads concurrently, > resulting in no "value changes" being observed. This is probably just > a limitation of TCG, and if run on a real CPU, shouldn't be a problem. > On QEMU, most test cases will pass with CONFIG_KCSAN_REPORT_VALUE_CHANGE_ONLY=n > (There's one left that requires value changes to be observable) > > 2. stack_trace_save() is subtly broken on s390: it starts the trace in > stack_trace_save() itself. This is incorrect, as the trace should > start with the caller. We reported something similar to arm64, also > because one of our sanitizer tests failed: > https://lkml.kernel.org/r/20210319184106.5688-1-mark.rutland@arm.com ... > I fixed it with the below, and now most tests pass. Note that, other > debugging tools may also report misleading stack traces without the > stack_trace_save() fix (e.g. certain KFENCE reports). > > If you have a better solution for how to fix stack_trace_save() on s390, > please discard my patch. Ah, with your patch I get the below on a real machine; so it looks like this really was the only problem for the failing self tests. Thanks a lot for the patch! Will look into it later and apply if everything else still works! [ 5.138547] ok 1 - test_basic [ 7.538799] ok 2 - test_concurrent_races [ 9.938524] ok 3 - test_novalue_change [ 11.620063] ok 4 - test_novalue_change_exception [ 11.952404] ok 5 - test_unknown_origin [ 14.349852] ok 6 - test_write_write_assume_atomic [ 14.681937] ok 7 - test_write_write_struct [ 15.031046] ok 8 - test_write_write_struct_part [ 17.429869] ok 9 - test_read_atomic_write_atomic [ 17.760862] ok 10 - test_read_plain_atomic_write [ 18.093500] ok 11 - test_read_plain_atomic_rmw [ 20.490570] ok 12 - test_zero_size_access [ 22.939270] ok 13 - test_data_race [ 23.271104] ok 14 - test_assert_exclusive_writer [ 23.601940] ok 15 - test_assert_exclusive_access [ 26.000281] ok 16 - test_assert_exclusive_access_writer [ 26.330718] ok 17 - test_assert_exclusive_bits_change [ 28.739480] ok 18 - test_assert_exclusive_bits_nochange [ 28.962218] ok 19 - test_assert_exclusive_writer_scoped [ 29.071385] ok 20 - test_assert_exclusive_access_scoped [ 31.479706] ok 21 - test_jiffies_noreport [ 33.879581] ok 22 - test_seqlock_noreport [ 36.279853] ok 23 - test_atomic_builtins [ 36.279893] ok 1 - kcsan