[PATCH] start_kernel: test if irq's got enabled early, barf, and disable them again

c4a68306 · Ard van Breemen <[email protected]> · 2007-01-05 16:36:19 -08:00

The calls made by parse_parms to other initialization code might enable
interrupts again way too early.

Having interrupts on this early can make systems PANIC when they initialize
the IRQ controllers (which happens later in the code).  This patch detects
that irq's are enabled again, barfs about it and disables them again as a
safety net.

[[email protected]: cleanups]
Signed-off-by: Ard van Breemen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Commit: c4a68306b9c0939b3facdad2cc5e34d660ff463a
Parents: 34f1ca54

Changes

1 files changed · +5 −0

File	Status	Add	Del	Content
init/main.c	modified	+5	−0	View file

init/main.c

View file

diff --git a/init/main.c b/init/main.c
index 2b1cdaa..bc27d72 100644
--- a/init/main.c
+++ b/init/main.c
@@ -538,6 +538,11 @@ asmlinkage void __init start_kernel(void)
 	parse_args("Booting kernel", command_line, __start___param,
 		   __stop___param - __start___param,
 		   &unknown_bootoption);
+	if (!irqs_disabled()) {
+		printk(KERN_WARNING "start_kernel(): bug: interrupts were "
+				"enabled *very* early, fixing it\n");
+		local_irq_disable();
+	}
 	sort_main_extable();
 	trap_init();
 	rcu_init();