[PATCH] Make initramfs printk a warning on incorrect cpio type

It turns out that the "-c" option of cpio is highly unportable even between
distros let alone unix variants, and may actually make the wrong type of
cpio archive.  I just wasted quite some time on this, and the kernel can
detect this and warn about it (it's __init memory so it gets thrown away
and thus there is no runtime overhead)

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/init/initramfs.c b/init/initramfs.c
index d28c1094d7e5..85f04037ade1 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -182,6 +182,10 @@ static int __init do_collect(void)
 
 static int __init do_header(void)
 {
+        if (memcmp(collected, "070707", 6)==0) {
+                error("incorrect cpio method used: use -H newc option");
+                return 1;
+        }
         if (memcmp(collected, "070701", 6)) {
                 error("no cpio magic");
                 return 1;