uml: install panic notifier earlier

It turns out that if there's a panic early enough, UML will just sit there in
the LED-blinking loop because the panic notifier hadn't been installed yet.

This patch installs it earlier.

It also fixes the problem which exposed the hang, namely that if you give UML
a zero-sized initrd, it will ask alloc_bootmem for zero bytes, and that will
cause the panic.

While I was in initrd.c, I gave it a style makeover.

Prompted by checkpatch, I moved a couple extern declarations of uml_exitcode
to kern_util.h.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/um/include/kern_util.h b/arch/um/include/kern_util.h
index 625ca2924a56..715ffb5b95c1 100644
--- a/arch/um/include/kern_util.h
+++ b/arch/um/include/kern_util.h
@@ -9,6 +9,8 @@
 #include "sysdep/ptrace.h"
 #include "sysdep/faultinfo.h"
 
+extern int uml_exitcode;
+
 extern int ncpus;
 extern int kmalloc_ok;
 extern int nsyscalls;