From 835a463e190af87a36df681863db7c3ea7ba0d66 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20B=C3=A4chler?= Date: Thu, 3 Apr 2014 21:55:37 +0200 Subject: [PATCH 04/10] fs: Don't return 0 from get_anon_bdev MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 9e30cc9595303b27b48 removed an internal mount. This has the side-effect that rootfs now has FSID 0. Many userspace utilities assume that st_dev in struct stat is never 0, so this change breaks a number of tools in early userspace. Since we don't know how many userspace programs are affected, make sure that FSID is at least 1. References: http://article.gmane.org/gmane.linux.kernel/1666905 References: http://permalink.gmane.org/gmane.linux.utilities.util-linux-ng/8557 Cc: 3.14 Signed-off-by: Thomas Bächler --- fs/super.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/super.c b/fs/super.c index 80d5cf2..7624267 100644 --- a/fs/super.c +++ b/fs/super.c @@ -802,7 +802,10 @@ void emergency_remount(void) static DEFINE_IDA(unnamed_dev_ida); static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */ -static int unnamed_dev_start = 0; /* don't bother trying below it */ +/* Many userspace utilities consider an FSID of 0 invalid. + * Always return at least 1 from get_anon_bdev. + */ +static int unnamed_dev_start = 1; int get_anon_bdev(dev_t *p) { -- 1.9.2