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=-2.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_NEOMUTT 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 74D1DC48BE0 for ; Fri, 21 Jun 2019 12:44:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C89F21530 for ; Fri, 21 Jun 2019 12:44:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=shutemov-name.20150623.gappssmtp.com header.i=@shutemov-name.20150623.gappssmtp.com header.b="B//niuCs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726713AbfFUMoD (ORCPT ); Fri, 21 Jun 2019 08:44:03 -0400 Received: from mail-ed1-f65.google.com ([209.85.208.65]:46699 "EHLO mail-ed1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726260AbfFUMoD (ORCPT ); Fri, 21 Jun 2019 08:44:03 -0400 Received: by mail-ed1-f65.google.com with SMTP id d4so9858256edr.13 for ; Fri, 21 Jun 2019 05:44:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=OqVBZEPWFSP/e9s0tB0Ipt3Dw5LvuQwd4dI9ko39cRU=; b=B//niuCskz8qf17kB7Iq3o6K45T58/nDnBXWjN/lMtJrjgnyfvaL2a31L14a+fI2p+ 5ChVYoeC82xkf1EHe2lYG+Bl/oyGAgO54WMGewBL1psB3FSD5b4tl9tMsxcoRW/6yIER kmTdftp73gm5VP9cZaPDBdc/oUezHnco0r2TCH3bNn9B4PABUavvKWsX4RiyWBruSJHq vNjuu5eDcmFQEIdQg3r+0jA131TpF6fLOoWd8ebt6ejVko6orgnK4PaS0pbVmtU+IYzJ 0OTl/a1Z596ofyzBk40B7tabxY4eKlGFQ0oZKKaAGrKElE9YTyiRHv9JT9lrewUYCXlp CJ/w== 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:user-agent; bh=OqVBZEPWFSP/e9s0tB0Ipt3Dw5LvuQwd4dI9ko39cRU=; b=mwKjrZ7TMNwsQQUNCkK0zuKgkRaeQHhtLSgOuDONsH4qeON4P/+q0UQS5mZq+u0Bhu P770nZnhU+hR5/zOpvBwzf/Kn9k/vv0Q8RkFfML0G++SkXCoIh3+i7uNKy+Wyb618yCz D4QncZUDEIdvvjgxsxkg2AxE8eDKln9TR2ySlDW8+ooQE4Cnx1LZWq7/rSxzfehnpV5E VTj9+Vtrt+v5FqfKXKaBdtfrYmG19hlouS6eBEYvYexTbPXEZqItitKiRNUubilDswYv mYQYqfD0pr+PQiJSXduE+uuTlj8tby6SIKRHcPmgjKQFSbnT6dCbGWKAybQ19qSMpFaq jkOw== X-Gm-Message-State: APjAAAXS88qiszCLsxQ0RzUZDyWa46XzulmHE2XTYnI8AILrG/FfuX+b 764ipzfgyeIs1vH1sf+LMTLhpA== X-Google-Smtp-Source: APXvYqyuPh8UjXLvvCCKNbaorIU7bGuaPuVf4C/aLJivx/vVf6Ln9WpleDFHzTJZF8WmtQPEuHB/lw== X-Received: by 2002:a50:ec03:: with SMTP id g3mr84559343edr.233.1561121041750; Fri, 21 Jun 2019 05:44:01 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id i21sm404358ejc.79.2019.06.21.05.44.00 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 21 Jun 2019 05:44:00 -0700 (PDT) Received: by box.localdomain (Postfix, from userid 1000) id CF12B10289C; Fri, 21 Jun 2019 15:44:02 +0300 (+03) Date: Fri, 21 Jun 2019 15:44:02 +0300 From: "Kirill A. Shutemov" To: Song Liu Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, oleg@redhat.com, rostedt@goodmis.org, mhiramat@kernel.org, matthew.wilcox@oracle.com, kirill.shutemov@linux.intel.com, kernel-team@fb.com Subject: Re: [PATCH v4 3/5] mm, thp: introduce FOLL_SPLIT_PMD Message-ID: <20190621124402.z4l67ck4vr5g7xe3@box> References: <20190613175747.1964753-1-songliubraving@fb.com> <20190613175747.1964753-4-songliubraving@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190613175747.1964753-4-songliubraving@fb.com> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 13, 2019 at 10:57:45AM -0700, Song Liu wrote: > @@ -419,6 +419,11 @@ static struct page *follow_pmd_mask(struct vm_area_struct *vma, > put_page(page); > if (pmd_none(*pmd)) > return no_page_table(vma, flags); > + } else { /* flags & FOLL_SPLIT_PMD */ > + spin_unlock(ptl); > + ret = 0; > + split_huge_pmd(vma, pmd, address); > + pte_alloc(mm, pmd); pte_alloc() can fail and the failure should be propogated to the caller. -- Kirill A. Shutemov