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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A355BC433F5 for ; Mon, 27 Sep 2021 17:39:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 712B060F3A for ; Mon, 27 Sep 2021 17:39:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235961AbhI0Rle (ORCPT ); Mon, 27 Sep 2021 13:41:34 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:59949 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237484AbhI0Rk6 (ORCPT ); Mon, 27 Sep 2021 13:40:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1632764359; 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=NdtzMn+WC7NxHhaIPrEy29/cG597R32mr5hQD2dXXIU=; b=dR0xSXmcS1zTUrJwNGBUkQ0Buk3RaWT8VyPmC+zU5bpeCojA2G1hwKpz1eZcWXpdu91Du2 MuLDyxfr9li4UhEl/bZ/4RtdUAAMCWJtwUDQZImORU83vfyyapaIa4+xHi78kpFmtQtG+Y lV5c2U1oDr9iPV13AnCDkYk9kB97fbQ= Received: from mail-io1-f69.google.com (mail-io1-f69.google.com [209.85.166.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-10-cYS6GCbqMxmX442qO73yAw-1; Mon, 27 Sep 2021 13:39:18 -0400 X-MC-Unique: cYS6GCbqMxmX442qO73yAw-1 Received: by mail-io1-f69.google.com with SMTP id m19-20020a6bea13000000b005d751644a6eso10810700ioc.15 for ; Mon, 27 Sep 2021 10:39:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=NdtzMn+WC7NxHhaIPrEy29/cG597R32mr5hQD2dXXIU=; b=q15wFvR/r0u+2UzrqKA8OsIev8sAfWFdLXQOPMMksdDj0TWBJLtmK9u4yqoHer7E55 Dk+cRQihuTS74TIonlZXFDrA/kBMsHjPBZbp9NOJwxvN33mT2WnUTCRWYNPG00SsFcct OngrgTWQLpFQd1MbEa4hM9qZ1JsQLxXrtRLYgrgCHR3u2zpe0pQSctnoV8s6P6SxgOUC oumf5Y+GxnNVAW7+to8i/iZxbY/fYpnk5ChyoH7UVRNQCZlAPiayslD4wXJfrcPKLQ5u IOZHTHlfZ0GkfLKOj7uPDcgpIfG9SVGcstVMY0l48c6VreuuswgMqxpD0unebHs2QK9z uh6g== X-Gm-Message-State: AOAM530ws7C3HSB81PeMT+whKbjBtzjok2HVgiV+W/bQuLuaEBz0jB0U +bVGmnM7cafNBUL83poyDA6tPQiXkHK8P/8J6pmtFzGnBQRq4/ZW057GpdQ3DNfmIoep8ESS5NF KsDlux+V2efTrzYOkpamRroJ/ X-Received: by 2002:a05:6e02:1065:: with SMTP id q5mr956314ilj.14.1632764357703; Mon, 27 Sep 2021 10:39:17 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwtzhiDWx+2ieyECJ0B7kImxGF2XnYiIelB+sXILXn1t4biruYRD/P0iUhweS3xhyS1ZKLjqQ== X-Received: by 2002:a05:6e02:1065:: with SMTP id q5mr956305ilj.14.1632764357534; Mon, 27 Sep 2021 10:39:17 -0700 (PDT) Received: from t490s ([2607:fea8:56a2:9100::d3ec]) by smtp.gmail.com with ESMTPSA id z4sm205924ilp.64.2021.09.27.10.39.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Sep 2021 10:39:16 -0700 (PDT) Date: Mon, 27 Sep 2021 13:39:15 -0400 From: Peter Xu To: Axel Rasmussen Cc: Linux MM , LKML , Andrew Morton , Andrea Arcangeli , Nadav Amit , Li Wang Subject: Re: [PATCH] mm/userfaultfd: selftests: Fix memory corruption with thp enabled Message-ID: References: <20210923232512.210092-1-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 27, 2021 at 10:34:06AM -0700, Axel Rasmussen wrote: > One possibility would be to MADV_NOHUGEPAGE the regions, which at > least would fix the immediate flakiness. Then we could spend some time > adding a test case which specifically targets THP interactions? (I do > think we want test coverage of that in the end, but with the current > tests it's kind of "accidental".) If we can't reproduce it with khugepaged yet, I'd think we can also consider keep torturing thp with this patch and at the meantime look for a clean approach? Now it's only the event test failing, if we apply NOHUGEPAGE we give up thp for all. -- Peter Xu