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>
diff --git a/arch/um/kernel/initrd.c b/arch/um/kernel/initrd.c
index ae31c62..fa01556 100644
--- a/arch/um/kernel/initrd.c
+++ b/arch/um/kernel/initrd.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
@@ -20,18 +20,27 @@
long long size;
int err;
- if(initrd == NULL)
+ if (initrd == NULL)
return 0;
err = os_file_size(initrd, &size);
- if(err)
+ if (err)
return 0;
+ /*
+ * This is necessary because alloc_bootmem craps out if you
+ * ask for no memory.
+ */
+ if (size == 0) {
+ printk(KERN_ERR "\"%\" is a zero-size initrd\n");
+ return 0;
+ }
+
area = alloc_bootmem(size);
- if(area == NULL)
+ if (area == NULL)
return 0;
- if(load_initrd(initrd, area, size) == -1)
+ if (load_initrd(initrd, area, size) == -1)
return 0;
initrd_start = (unsigned long) area;
@@ -58,13 +67,15 @@
int fd, n;
fd = os_open_file(filename, of_read(OPENFLAGS()), 0);
- if(fd < 0){
- printk("Opening '%s' failed - err = %d\n", filename, -fd);
+ if (fd < 0) {
+ printk(KERN_ERR "Opening '%s' failed - err = %d\n", filename,
+ -fd);
return -1;
}
n = os_read_file(fd, buf, size);
- if(n != size){
- printk("Read of %d bytes from '%s' failed, err = %d\n", size,
+ if (n != size) {
+ printk(KERN_ERR "Read of %d bytes from '%s' failed, "
+ "err = %d\n", size,
filename, -n);
return -1;
}