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=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 CAC28C433B4 for ; Sat, 24 Apr 2021 00:12:28 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2931961396 for ; Sat, 24 Apr 2021 00:12:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2931961396 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id AAD756B0036; Fri, 23 Apr 2021 20:12:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A5E4B6B006C; Fri, 23 Apr 2021 20:12:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8FD7B6B006E; Fri, 23 Apr 2021 20:12:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0111.hostedemail.com [216.40.44.111]) by kanga.kvack.org (Postfix) with ESMTP id 6CC4D6B0036 for ; Fri, 23 Apr 2021 20:12:27 -0400 (EDT) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 236A11827D86C for ; Sat, 24 Apr 2021 00:12:27 +0000 (UTC) X-FDA: 78065333934.11.32B4852 Received: from mail-ej1-f44.google.com (mail-ej1-f44.google.com [209.85.218.44]) by imf20.hostedemail.com (Postfix) with ESMTP id 5934A135 for ; Sat, 24 Apr 2021 00:12:17 +0000 (UTC) Received: by mail-ej1-f44.google.com with SMTP id n2so76181316ejy.7 for ; Fri, 23 Apr 2021 17:12:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=qHr7tUOXaQai/2OdZAuZvtKoquZIqzNXavanHLPXua4=; b=Zx4YtT/ak9bAKuxFjeh83s+2vCvsnhqW3WCOWH4QzP7FZDumo/tG8NEFlLRf/X/sbx YFUhP9uRlqwpI3tvdp2tiW7FVEXDjWLkB88vK9RtxYeM+kx5snSvvD+2Ugvc1PRL1saF uH/CLk8Mcqrg2WyECWStWddk61woeHpnR4f4uyysEdWMMKR/fzCtR11lVV65qWR6Iq+E c1fXjIlaM9+x9Jl1n005XVF0hQnEyoDeQu7d50p+OzI4PLRAJHKlMs5ToOR01asCBMk8 SG44A7i5NlRMdVttNuSG8NcItte4Gkfk044vNafdlz1AMqgObu+XiIuTsP1TtksYy+N6 fuNA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=qHr7tUOXaQai/2OdZAuZvtKoquZIqzNXavanHLPXua4=; b=QsGZ95XOZx76BA4NrcvbUVsExNpm2bZ05mbSATfTx1F7BiDQZZ6yRjSewxudXBn9SX QiKyqAhX5iD+8DGdsIZjsdjL9BWNZmejAtJlOCmCmoMMuIA+mXZKEqP7wrXDzHvzIpVV G+AaDIBZno41EEYyzDI6TIQwdANrwVoIUdueVYVDClIpWwx9UVCE3fFfUJdDFC+3o8Cl KJU41H1b8UENc/H2HFcu2JiSk19w4CrscJcYzBd6/lCzC/R7OYrgLLXkExE6mNtBwitw 0inzDWd5JgMNzu0h4FFlGjtCDcUw8MrQ3VGqoQTTh7zVavm1QssrHHCf4CwmAorRW2o6 VQ8g== X-Gm-Message-State: AOAM530AyWGDACvpEwFWSz5T/RTkqrPh8ER79LwfZzM+WzY+H88sM3By aBAxOua8ECHV2qCEaDwZJ8N/5LFJFSF8/nzWf6fJPw== X-Google-Smtp-Source: ABdhPJxw0VS3dz3A1xGOFxbEhcW7vCcLHVEkly52DIWEjT1QLF7rLt2Jx7ufHOUIpby/EW/WDEEg9aMUXcjUacu5Jzk= X-Received: by 2002:a17:907:7631:: with SMTP id jy17mr6812547ejc.418.1619223143985; Fri, 23 Apr 2021 17:12:23 -0700 (PDT) MIME-Version: 1.0 References: <20210325230938.30752-1-joao.m.martins@oracle.com> <20210325230938.30752-2-joao.m.martins@oracle.com> In-Reply-To: <20210325230938.30752-2-joao.m.martins@oracle.com> From: Dan Williams Date: Fri, 23 Apr 2021 17:12:18 -0700 Message-ID: Subject: Re: [PATCH v1 01/11] memory-failure: fetch compound_head after pgmap_pfn_valid() To: Joao Martins Cc: Linux MM , Ira Weiny , linux-nvdimm , Matthew Wilcox , Jason Gunthorpe , Jane Chu , Muchun Song , Mike Kravetz , Andrew Morton Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 5934A135 X-Stat-Signature: 477e17mdnuib7dwgk4qb69jk3muggq1d Received-SPF: none (intel.com>: No applicable sender policy available) receiver=imf20; identity=mailfrom; envelope-from=""; helo=mail-ej1-f44.google.com; client-ip=209.85.218.44 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619223137-12793 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Mar 25, 2021 at 4:10 PM Joao Martins wrote: > > memory_failure_dev_pagemap() at the moment assumes base pages (e.g. > dax_lock_page()). For pagemap with compound pages fetch the > compound_head in case we are handling a tail page memory failure. > > Currently this is a nop, but in the advent of compound pages in > dev_pagemap it allows memory_failure_dev_pagemap() to keep working. > > Reported-by: Jane Chu > Signed-off-by: Joao Martins > --- > mm/memory-failure.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 24210c9bd843..94240d772623 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1318,6 +1318,8 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > goto out; > } > > + page = compound_head(page); Unless / until we do compound pages for the filesystem-dax case, I would add a comment like: /* pages instantiated by device-dax (not filesystem-dax) may be compound pages */