From mboxrd@z Thu Jan 1 00:00:00 1970 From: Woody Suwalski Subject: Re: [PATCH] init/do_mounts.c : Create /root if it does not exits Date: Wed, 30 Nov 2011 19:24:25 -0500 Message-ID: <4ED6C939.9050403@gmail.com> References: <20111130125555.85ac54e7.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: yanhong , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Al Viro To: Andrew Morton Return-path: In-Reply-To: <20111130125555.85ac54e7.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Andrew Morton wrote: > 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. > I think that it may lead to more problems... If I make mistake in the initramfs or forget to make one I want to know about it, rather then see some unexpected root and system maybe partially booting. Unless we start printing a highly visible warning along? Still - it is cleaner to simply stop boot (IMHO). Woody