From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753623Ab1K3Uz6 (ORCPT ); Wed, 30 Nov 2011 15:55:58 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:54772 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753331Ab1K3Uz4 (ORCPT ); Wed, 30 Nov 2011 15:55:56 -0500 Date: Wed, 30 Nov 2011 12:55:55 -0800 From: Andrew Morton To: yanhong Cc: , linux-fsdevel@vger.kernel.org, Al Viro Subject: Re: [PATCH] init/do_mounts.c : Create /root if it does not exits Message-Id: <20111130125555.85ac54e7.akpm@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 26 Nov 2011 08:34:18 +0000 yanhong wrote: > > From: YanHong > > If someone supplies an initramfs without /root in it, and we fail to execute rdinit, we will try to mount root device and fail, for the mount point does not exits. > > But we get error message "VFS: Cannot open root device". It's confusing. > > We can give more detailed error message, or we can go further: if /root does not exits, create one. > I really don't know enough about initramfs usage to know if this is a good or bad thing. Can anyone else comment? > --- a/init/do_mounts.c > +++ b/init/do_mounts.c > @@ -350,6 +350,9 @@ void __init mount_block_root(char *name, int flags) > const char *b = name; > #endif > > + if (sys_access((const char __user *) "/root", 0) != 0) > + sys_mkdir((const char __user *) "/root", 0700); > + > get_fs_names(fs_names); > retry: > for (p = fs_names; *p; p += strlen(p)+1) { I suppose we could remove the sys_access() check and just run mkdir(), which will fail to do anything if /root already exists.