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/um_arch.c b/arch/um/kernel/um_arch.c
index 9ba39ab..cb7eef8 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -223,6 +223,23 @@
return;
}
+static int panic_exit(struct notifier_block *self, unsigned long unused1,
+ void *unused2)
+{
+ bust_spinlocks(1);
+ show_regs(&(current->thread.regs));
+ bust_spinlocks(0);
+ uml_exitcode = 1;
+ os_dump_core();
+ return 0;
+}
+
+static struct notifier_block panic_exit_notifier = {
+ .notifier_call = panic_exit,
+ .next = NULL,
+ .priority = 0
+};
+
/* Set during early boot */
unsigned long brk_start;
unsigned long end_iomem;
@@ -327,6 +344,9 @@
printf("Kernel virtual memory size shrunk to %lu bytes\n",
virtmem_size);
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &panic_exit_notifier);
+
uml_postsetup();
stack_protections((unsigned long) &init_thread_info);
@@ -335,29 +355,8 @@
return start_uml();
}
-extern int uml_exitcode;
-
-static int panic_exit(struct notifier_block *self, unsigned long unused1,
- void *unused2)
-{
- bust_spinlocks(1);
- show_regs(&(current->thread.regs));
- bust_spinlocks(0);
- uml_exitcode = 1;
- os_dump_core();
- return 0;
-}
-
-static struct notifier_block panic_exit_notifier = {
- .notifier_call = panic_exit,
- .next = NULL,
- .priority = 0
-};
-
void __init setup_arch(char **cmdline_p)
{
- atomic_notifier_chain_register(&panic_notifier_list,
- &panic_exit_notifier);
paging_init();
strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
*cmdline_p = command_line;
