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

Sam Ravnborg
2008-12-26T10:25:59Z

On Fri, Dec 26, 2008 at 02:05:47AM -0800, Yinghai Lu wrote:
> Kamalesh Babulal wrote:
> > * Yinghai Lu <yinghai@kernel.org> [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?

I recall David Howells had a similar issue with the bootparamter patch set.
The workaround he used was to add a barrier(); call in the weak function
to avoid the inline.

[full context kept as I added David to to: list].
Sam

>
> 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 <yinghai@kernel.org>
>
> ---
> 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)
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/