Subject: Re: [BUG] next-20081216 - WARNING: at kernel/smp.c:333 smp_call_function_mask

From: Yinghai Lu <[email-masked]>
Date: Fri, 26 Dec 2008 02:05:47 -0800

Kamalesh Babulal wrote:
> * Yinghai Lu <[email-masked]> [2008-12-24 12:34:41]:
> 
>> --
> 
> After the applying the patch, the kernel panic's with the same backtrace. The
> box is running Fedora 5 on it.
> 

please try...
Ingo, do we need to switch to use #idef and inline function instead?

YH

[PATCH] sparseirq: add printk to workaround compiler optimizing

Impact: fix panic on null pointer with sparseirq

some compiler seems to inline the weak global function.
try to workaround it

also remove duplicated arch_early_irq_init()
already have one weak copy in init/main.c

Signed-off-by: Yinghai <[email-masked]>

---
 init/main.c         |    2 ++
 kernel/irq/handle.c |    7 ++-----
 2 files changed, 4 insertions(+), 5 deletions(-)

Index: linux-2.6/init/main.c
===================================================================
--- linux-2.6.orig/init/main.c
+++ linux-2.6/init/main.c
@@ -544,10 +544,12 @@ void __init __weak thread_info_cache_ini
 
 void __init __weak arch_early_irq_init(void)
 {
+	printk(KERN_DEBUG "calling __weak arch_early_irq_init\n");
 }
 
 void __init __weak early_irq_init(void)
 {
+	printk(KERN_DEBUG "calling __weak early_irq_init\n");
 	arch_early_irq_init();
 }
 
Index: linux-2.6/kernel/irq/handle.c
===================================================================
--- linux-2.6.orig/kernel/irq/handle.c
+++ linux-2.6/kernel/irq/handle.c
@@ -56,10 +56,6 @@ void handle_bad_irq(unsigned int irq, st
 int nr_irqs = NR_IRQS;
 EXPORT_SYMBOL_GPL(nr_irqs);
 
-void __init __attribute__((weak)) arch_early_irq_init(void)
-{
-}
-
 #ifdef CONFIG_SPARSE_IRQ
 static struct irq_desc irq_desc_init = {
 	.irq	    = -1,
@@ -90,8 +86,9 @@ void init_kstat_irqs(struct irq_desc *de
 		desc->kstat_irqs = (unsigned int *)ptr;
 }
 
-void __attribute__((weak)) arch_init_chip_data(struct irq_desc *desc, int cpu)
+void __weak arch_init_chip_data(struct irq_desc *desc, int cpu)
 {
+	printk(KERN_DEBUG "calling __weak arch_init_chip_data\n");
 }
 
 static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)