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 X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, URIBL_RED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1A797C433B4 for ; Sun, 9 May 2021 04:10:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC1D56142D for ; Sun, 9 May 2021 04:10:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229502AbhEIELE (ORCPT ); Sun, 9 May 2021 00:11:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:60506 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229585AbhEIELC (ORCPT ); Sun, 9 May 2021 00:11:02 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 131FF613FA; Sun, 9 May 2021 04:09:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1620533399; bh=8ObyEW6yGEt206dYX/GYSZtBdRf1vXYBEF4iCK4F1lI=; h=Date:From:To:Subject:From; b=xupLHSSUlPij/7IRFrgjVfusb30CaH19WlRRs97FgjPEAPM419V2Lqv+IInMFuQPa 6MI1L7T/awbWPolMmBn1QFzBltyCy9UbV0i1dMGTGMuCrpvYmUDdRUYb9sOgTxJYWJ U6NgAKuoqrYt6ys9Y1gRVpn04KpsRc1ySZmJPF/o= Date: Sat, 08 May 2021 21:09:58 -0700 From: akpm@linux-foundation.org To: aarcange@redhat.com, almasrymina@google.com, axelrasmussen@google.com, bgeffon@google.com, dgilbert@redhat.com, hughd@google.com, jglisse@redhat.com, joe@perches.com, kirill@shutemov.name, lokeshgidra@google.com, mike.kravetz@oracle.com, mm-commits@vger.kernel.org, oupton@google.com, peterx@redhat.com, rppt@linux.vnet.ibm.com, sfr@canb.auug.org.au, shli@fb.com, shuah@kernel.org, viro@zeniv.linux.org.uk, wangqing@vivo.com Subject: + userfaultfd-selftests-remove-the-time-check-on-delayed-uffd.patch added to -mm tree Message-ID: <20210509040958.emeAN3ynW%akpm@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: userfaultfd/selftests: remove the time() check on delayed uffd has been added to the -mm tree. Its filename is userfaultfd-selftests-remove-the-time-check-on-delayed-uffd.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/userfaultfd-selftests-remove-the-time-check-on-delayed-uffd.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/userfaultfd-selftests-remove-the-time-check-on-delayed-uffd.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Peter Xu Subject: userfaultfd/selftests: remove the time() check on delayed uffd There seems to have no guarantee that time() will return the same for the two calls even if there's no delay, e.g. when a fault is accidentally crossing the changing of a second. Meanwhile, this message is also not helping that much since delay could happen with a lot of reasons, e.g., schedule latency of resolving thread. It may not mean an issue with uffd. Neither do I saw this error triggered either in the past runs. Even if it triggers, it'll be drown in all the rest of test logs. Remove it. Link: https://lkml.kernel.org/r/20210412232753.1012412-3-peterx@redhat.com Signed-off-by: Peter Xu Reviewed-by: Axel Rasmussen Cc: Alexander Viro Cc: Andrea Arcangeli Cc: Brian Geffon Cc: "Dr . David Alan Gilbert" Cc: Hugh Dickins Cc: Jerome Glisse Cc: Joe Perches Cc: Kirill A. Shutemov Cc: Lokesh Gidra Cc: Mike Kravetz Cc: Mike Rapoport Cc: Mina Almasry Cc: Oliver Upton Cc: Shaohua Li Cc: Shuah Khan Cc: Stephen Rothwell Cc: Wang Qing Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/userfaultfd.c | 8 -------- 1 file changed, 8 deletions(-) --- a/tools/testing/selftests/vm/userfaultfd.c~userfaultfd-selftests-remove-the-time-check-on-delayed-uffd +++ a/tools/testing/selftests/vm/userfaultfd.c @@ -395,7 +395,6 @@ static void *locking_thread(void *arg) unsigned long long count; char randstate[64]; unsigned int seed; - time_t start; if (bounces & BOUNCE_RANDOM) { seed = (unsigned int) time(NULL) - bounces; @@ -432,7 +431,6 @@ static void *locking_thread(void *arg) page_nr += 1; page_nr %= nr_pages; - start = time(NULL); if (bounces & BOUNCE_VERIFY) { count = *area_count(area_dst, page_nr); if (!count) { @@ -495,12 +493,6 @@ static void *locking_thread(void *arg) count++; *area_count(area_dst, page_nr) = count_verify[page_nr] = count; pthread_mutex_unlock(area_mutex(area_dst, page_nr)); - - if (time(NULL) - start > 1) - fprintf(stderr, - "userfault too slow %ld " - "possible false positive with overcommit\n", - time(NULL) - start); } return NULL; _ Patches currently in -mm which might be from peterx@redhat.com are mm-hugetlb-fix-f_seal_future_write.patch mm-hugetlb-fix-cow-where-page-writtable-in-child.patch mm-gup_benchmark-support-threading.patch userfaultfd-selftests-use-user-mode-only.patch userfaultfd-selftests-remove-the-time-check-on-delayed-uffd.patch userfaultfd-selftests-dropping-verify-check-in-locking_thread.patch userfaultfd-selftests-only-dump-counts-if-mode-enabled.patch userfaultfd-selftests-unify-error-handling.patch mm-thp-simplify-copying-of-huge-zero-page-pmd-when-fork.patch mm-userfaultfd-fix-uffd-wp-special-cases-for-fork.patch mm-userfaultfd-fix-a-few-thp-pmd-missing-uffd-wp-bit.patch mm-userfaultfd-fail-uffd-wp-registeration-if-not-supported.patch mm-pagemap-export-uffd-wp-protection-information.patch userfaultfd-selftests-add-pagemap-uffd-wp-test.patch