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=-20.8 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,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 4CE14C4320E for ; Mon, 30 Aug 2021 12:40:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 336D360C40 for ; Mon, 30 Aug 2021 12:40:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234822AbhH3Mlq (ORCPT ); Mon, 30 Aug 2021 08:41:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51392 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233505AbhH3Mlo (ORCPT ); Mon, 30 Aug 2021 08:41:44 -0400 Received: from mail-qv1-xf34.google.com (mail-qv1-xf34.google.com [IPv6:2607:f8b0:4864:20::f34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5185BC061760 for ; Mon, 30 Aug 2021 05:40:51 -0700 (PDT) Received: by mail-qv1-xf34.google.com with SMTP id a5so8220268qvq.0 for ; Mon, 30 Aug 2021 05:40:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=T0GjF5w0oMuRtLInC2hBs3sq1EKkXCp946NJQvmrNNA=; b=YJz06bSaVp5ajqLNrj0z3k7B2zNq9W3juYAjTRacLX1OTnWl+Y2TCuZRXrDpNev5ES LI9vF8Ek/BlSVqhQxxZNTzpA5FUjX/13eTlFBMEzsXx19XkdMbZPqCBpO+RkihfEnj0l J5p6+wZXhw44KfNzMBWBNzDL/r8IzJMq1PUz9AGeK1i6zpPFRaQj7/uzkd9BXt9TCJfc W42wzWo2iZS4pWlUgqlA7jUlEn0stzTigVCRnRBofn3VEjYosxE04T10wIyEgIow15e4 4JqWV2i7dl5xXX5bp87lKznKwdqX/+WO93wXw52VHRAZmCWLEEbhZctMAempuTEerRIF bm2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=T0GjF5w0oMuRtLInC2hBs3sq1EKkXCp946NJQvmrNNA=; b=M/VGEHdzodWy91ch7oIlZL6OzUnGGxHpqHMjLxBOrNw/e26b0HzBwNcppIzCvznA4y wHYTne315+atP3za8a2EZsKg3Dj5q7OxlMfnLkiuwopZk8YAJf7tBBfTsQ0RYZkdXnRV J835ZKzQIb7MqElzI8wE2yXWQiWi8+TE/VjXhOQaOJP2IJdayWosbuc6hlsL+6udrD9G Su3Hc16FaDPzy6l9RXSA2+zMSgWgvFRGWGgKVdqBR8zGIRSMm2QlQztQquzCEvCBnyzp bQhXa2SurBx+L+eMUZpE8wzPYhIP6dzH5UqSc0p4b7d6fxnkWutE92g3J9rlueLxDdyT h8bA== X-Gm-Message-State: AOAM531KGbsZECxbLDPGYG9SRXPZXbQCLNOzV2jYDsyuhxlH0RMpFevi Tcii3RbCLEi9zkRZaGxcL1adSA== X-Google-Smtp-Source: ABdhPJyaf6VQxCJ00UbLfwPFp16U/tNv3663ulooWB0/urnMOTvjl6SDaLLUsNSISMLXKOIbvLqaHA== X-Received: by 2002:a0c:e70f:: with SMTP id d15mr22462454qvn.47.1630327250483; Mon, 30 Aug 2021 05:40:50 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-142-162-113-129.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.162.113.129]) by smtp.gmail.com with ESMTPSA id c10sm8262652qtb.20.2021.08.30.05.40.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Aug 2021 05:40:49 -0700 (PDT) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1mKgan-0070tA-0m; Mon, 30 Aug 2021 09:40:49 -0300 Date: Mon, 30 Aug 2021 09:40:49 -0300 From: Jason Gunthorpe To: Li Zhijian , akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-rdma@vger.kernel.org, jglisse@redhat.com, hch@infradead.org, yishaih@nvidia.com, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH v3] mm/hmm: bypass devmap pte when all pfn requested flags are fulfilled Message-ID: <20210830124049.GN1200268@ziepe.ca> References: <20210830094232.203029-1-lizhijian@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210830094232.203029-1-lizhijian@cn.fujitsu.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 30, 2021 at 05:42:32PM +0800, Li Zhijian wrote: > Previously, we noticed the one rpma example was failed[1] since 36f30e486d, > where it will use ODP feature to do RDMA WRITE between fsdax files. > > After digging into the code, we found hmm_vma_handle_pte() will still > return EFAULT even though all the its requesting flags has been > fulfilled. That's because a DAX page will be marked as > (_PAGE_SPECIAL | PAGE_DEVMAP) by pte_mkdevmap(). > > [1]: https://github.com/pmem/rpma/issues/1142 > > CC: stable@vger.kernel.org > Fixes: 405506274922 ("mm/hmm: add missing call to hmm_pte_need_fault in HMM_PFN_SPECIAL handling") > Signed-off-by: Li Zhijian > > --- > V3: adjust the checking order > --- > mm/hmm.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) Reviewed-by: Jason Gunthorpe Andrew, can you grab this please? Thanks, Jason