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 C3FF7C433FE for ; Mon, 3 Oct 2022 15:56:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229711AbiJCP4n (ORCPT ); Mon, 3 Oct 2022 11:56:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53742 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229570AbiJCP4g (ORCPT ); Mon, 3 Oct 2022 11:56:36 -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 ESMTPS id DE84C2CCBA for ; Mon, 3 Oct 2022 08:56:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1664812594; 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: content-transfer-encoding:content-transfer-encoding; bh=c+kdz5cc3NrJArhDY2JgimgASSW1d1LMZTKXqfIaym0=; b=HEt5J27PULF+xYKbuqsfzXr5JFagp9DzFuumogbkWsa5bHesqoRU8s5wlCp4uPxIXVVbAQ dAAd+8jCnybGrbwyFlkjYdM9B3mO3Qg+sZNdbcyKMwQOCVpbmfq/LUn1+oMHceqsn2KICE EX7LONde08hgYPeyUpwB6ZeeLRxgk+Q= Received: from mail-qk1-f199.google.com (mail-qk1-f199.google.com [209.85.222.199]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-597-HjfK0IK8PJeH1zrfLbaJkA-1; Mon, 03 Oct 2022 11:56:33 -0400 X-MC-Unique: HjfK0IK8PJeH1zrfLbaJkA-1 Received: by mail-qk1-f199.google.com with SMTP id az15-20020a05620a170f00b006cece4cd0beso9494402qkb.22 for ; Mon, 03 Oct 2022 08:56:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date; bh=c+kdz5cc3NrJArhDY2JgimgASSW1d1LMZTKXqfIaym0=; b=YDjFWympkI15o/n5EjoT06FiZx53EiBmRTFhfhkRBikACH5K32wM4zDwzcN4ya/Am6 XLgNI3sR+AG/3z3Ee+9OXdqsIL+efHq+9gvIqMhHt5Kciru+ZpC/sbXDUXkvW3vBEDka r/62h4NeBP9qs7SSilqLCiCOkJ7wpFvbCc807NW5HUGB2FHS4EkLrPn/6f+0HOeVpBGm RDyCgPm34U+rG3ynNVs3li0Xj6H0+dpU2o6NoGNhHhfXPYsSfhxbOv2tIDEkklul38x+ DifrgNAMJi40qtJKDGnGCFBfVWvOay4oTz89qQlT720UWUNzaJoygAxS1kEs2nouF6r9 5mmw== X-Gm-Message-State: ACrzQf39MqSs9FqnpfqZzVQLOAKuTBL+1kx0f6YXiwkQQpgVVhGF8Iup RUS0H/fKG+GOv9RRzuvRQA7HD43xyLMS8ESacQYClG4A2XQZV1oHokXHUyziWCjzdNKkI+zwhHW lhQglFVS8i4NeklUr0c5IKtP4IGLJvmFuooUCkabwoYKfYQXpjxIdU1KmfxvBBjVQIlYpB4OYwg == X-Received: by 2002:a05:620a:1a8f:b0:6ce:7d4e:6bf8 with SMTP id bl15-20020a05620a1a8f00b006ce7d4e6bf8mr13686644qkb.349.1664812592986; Mon, 03 Oct 2022 08:56:32 -0700 (PDT) X-Google-Smtp-Source: AMsMyM772dQHPW6o9PwTFwZTSvMd0ETbKDy6p1qmmy6Hv9ZpUfc2C7s+ziRT/FDrpRICFT2iN9vS6g== X-Received: by 2002:a05:620a:1a8f:b0:6ce:7d4e:6bf8 with SMTP id bl15-20020a05620a1a8f00b006ce7d4e6bf8mr13686625qkb.349.1664812592729; Mon, 03 Oct 2022 08:56:32 -0700 (PDT) Received: from x1n.redhat.com (bras-base-aurron9127w-grc-46-70-31-27-79.dsl.bell.ca. [70.31.27.79]) by smtp.gmail.com with ESMTPSA id bs18-20020a05620a471200b006cf38fd659asm10956732qkb.103.2022.10.03.08.56.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 03 Oct 2022 08:56:32 -0700 (PDT) From: Peter Xu To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: peterx@redhat.com, Andrea Arcangeli , Mike Rapoport , David Hildenbrand , Andrew Morton , Axel Rasmussen , Mike Kravetz , Nadav Amit Subject: [PATCH 0/3] mm/hugetlb: Fix selftest failures with write check Date: Mon, 3 Oct 2022 11:56:27 -0400 Message-Id: <20221003155630.469263-1-peterx@redhat.com> X-Mailer: git-send-email 2.37.3 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently akpm mm-unstable fails with uffd hugetlb private mapping test randomly on a write check. The initial bisection of that points to the recent pmd unshare series, but it turns out there's no direction relationship with the series but only some timing change caused the race to start trigger. The race should be fixed in patch 1. Patch 2 is a trivial cleanup on the similar race with hugetlb migrations, patch 3 comment on the write check so when anyone read it again it'll be clear why it's there. Thanks, Peter Xu (3): mm/hugetlb: Fix race condition of uffd missing/minor handling mm/hugetlb: Use hugetlb_pte_stable in migration race check mm/selftest: uffd: Explain the write missing fault check mm/hugetlb.c | 62 ++++++++++++++++++++---- tools/testing/selftests/vm/userfaultfd.c | 22 ++++++++- 2 files changed, 73 insertions(+), 11 deletions(-) -- 2.37.3