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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 DB65BC10DCE for ; Wed, 18 Mar 2020 05:22:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 69D2E2076A for ; Wed, 18 Mar 2020 05:22:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 69D2E2076A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=vivo.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0A0046B0003; Wed, 18 Mar 2020 01:22:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0514A6B0006; Wed, 18 Mar 2020 01:22:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EA87A6B0007; Wed, 18 Mar 2020 01:22:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0064.hostedemail.com [216.40.44.64]) by kanga.kvack.org (Postfix) with ESMTP id D0A196B0003 for ; Wed, 18 Mar 2020 01:22:40 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id ECC038245571 for ; Wed, 18 Mar 2020 05:22:40 +0000 (UTC) X-FDA: 76607338080.08.wren12_8bb76f3da1424 X-HE-Tag: wren12_8bb76f3da1424 X-Filterd-Recvd-Size: 2100 Received: from m17617.mail.qiye.163.com (m17617.mail.qiye.163.com [59.111.176.17]) by imf07.hostedemail.com (Postfix) with SMTP for ; Wed, 18 Mar 2020 05:22:39 +0000 (UTC) Received: from ubuntu.localdomain (unknown [58.251.74.227]) by m17617.mail.qiye.163.com (Hmail) with ESMTPA id E5CB2261414; Wed, 18 Mar 2020 13:22:33 +0800 (CST) From: Wang Wenhu To: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: trivial@kernel.org, kernel@vivo.com, Wang Wenhu Subject: [PATCH] mm: clarify a confusing comment for vm_iomap_memory Date: Tue, 17 Mar 2020 22:22:06 -0700 Message-Id: <20200318052206.105104-1-wenhu.wang@vivo.com> X-Mailer: git-send-email 2.17.1 X-HM-Spam-Status: e1kfGhgUHx5ZQUtXWQgYFAkeWUFZTlVPSEpCQkJNQ0hIQ0tKSFlXWShZQU hPN1dZLVlBSVdZCQ4XHghZQVk1NCk2OjckKS43PlkG X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6Okk6ERw5TjgyTzQtPTwXCRwK AhoKFE1VSlVKTkNPTktDQk5NT05LVTMWGhIXVQweFRMOVQwaFRw7DRINFFUYFBZFWVdZEgtZQVlO Q1VJTkpVTE9VSUlMWVdZCAFZQUpMSUk3Bg++ X-HM-Tid: 0a70ec17e6e69375kuwse5cb2261414 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: The param "start" actually referes to the physical memory start, which is to be mapped into virtual area vma. And it is the field vma->vm_start which stands for the start of the area. Most of the time, we do not read through whole implementation of a function but only the definition and essential comments. Accurate comments are definitely the base stone. Signed-off-by: Wang Wenhu --- mm/memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/memory.c b/mm/memory.c index 583f84519870..5c356a57b892 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2009,7 +2009,7 @@ EXPORT_SYMBOL(remap_pfn_range); /** * vm_iomap_memory - remap memory to userspace * @vma: user vma to map to - * @start: start of area + * @start: start of the physical memory to be mapped * @len: size of area * * This is a simplified io_remap_pfn_range() for common driver use. The -- 2.17.1