From 70a0a5357db20c291d46c04011d646d5d84c868c Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 25 Oct 2006 01:00:23 +0200 Subject: [PATCH] x86-64: Only look at per_cpu data for online cpus. When I generalized __assign_irq_vector I failed to pay attention to what happens when you access a per cpu data structure for a cpu that is not online. It is an undefined case making any code that does it have undefined behavior as well. The code still needs to be able to allocate a vector across cpus that are not online to properly handle combinations like lowest priority interrupt delivery and cpu_hotplug. Not that we can do that today but the infrastructure shouldn't prevent it. So this patch updates the places where we touch per cpu data to only touch online cpus, it makes cpu vector allocation an atomic operation with respect to cpu hotplug, and it updates the cpu start code to properly initialize vector_irq so we don't have inconsistencies. Signed-off-by: Eric W. Biederman Signed-off-by: Andi Kleen --- include/asm-x86_64/hw_irq.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/asm-x86_64/hw_irq.h b/include/asm-x86_64/hw_irq.h index 792dd52fcd70..179cce755aa7 100644 --- a/include/asm-x86_64/hw_irq.h +++ b/include/asm-x86_64/hw_irq.h @@ -76,6 +76,8 @@ #ifndef __ASSEMBLY__ typedef int vector_irq_t[NR_VECTORS]; DECLARE_PER_CPU(vector_irq_t, vector_irq); +extern void __setup_vector_irq(int cpu); +extern spinlock_t vector_lock; /* * Various low-level irq details needed by irq.c, process.c, -- cgit v1.2.1