On Wed, 26 Nov 2008, Wu Fengguang wrote: > [add CC to <stable@xxxxxxxxxx>, since this bug was introduced in the > 2.6.27-rcX time frame, and should help 2.6.28 and 2.6.27.x alike] Actually, ACPI_PREEMPTION_POINT() went in to 2.6.28-rc1, it is not present in 2.6.27.stable so this patch does not apply to 27.stable. > The ACPI routines could be called from run_workqueue() with irqs disabled. > So we should test irqs_disabled() before calling cond_resched(). I don't know how you provoked this failure. The ACPI interpreter should always be run with interrupts enabled. If it isn't then that is a (different) bug. There is, however, one exception, and it is during suspend/resume; and that _is_ a legal way to provoke this bug: http://bugzilla.kernel.org/show_bug.cgi?id=12252 and thus the fix is actually correct, and I'll apply it. thanks, -- Len Brown, Intel Open Source Technology Center > --- a/include/acpi/platform/aclinux.h > +++ b/include/acpi/platform/aclinux.h > @@ -141,6 +141,10 @@ static inline void *acpi_os_acquire_object(acpi_cache_t * cache) > /* > * We need to show where it is safe to preempt execution of ACPICA > */ > -#define ACPI_PREEMPTION_POINT() cond_resched() > +#define ACPI_PREEMPTION_POINT() \ > + do { \ > + if (!irqs_disabled()) \ > + cond_resched(); \ > + } while (0) > > #endif /* __ACLINUX_H__ */ > -- -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
