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27 March 2024, 02:37:15 UTC
Revision 8cc3cfc5ccf1680b7c88f874912b6bec2797b76b authored by Thomas Gleixner on 04 March 2014, 20:43:41 UTC, committed by Thomas Gleixner on 28 April 2014, 19:27:15 UTC 
irqchip: armanda: Sanitize set_irq_affinity()
 
The set_irq_affinity() function has two issues:

1) It has no protection against selecting an offline cpu from the
   given mask.

2) It pointlessly restricts the affinity masks to have a single cpu
   set. This collides with the irq migration code of arm.

   irq affinity is set to core 3
   core 3 goes offline

   migration code sets mask to cpu_online_mask and calls the
   irq_set_affinity() callback of the irq_chip which fails due to bit
   0,1,2 set.

So instead of doing silly for_each_cpu() loops just pick any bit of
the mask which intersects with the online mask.

Get rid of fiddling with the default_irq_affinity as well.

[ Gregory: Fixed the access to the routing register ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/20140304203101.088889302@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
1 parent 62a08ae
Raw File
Tip revision: 8cc3cfc5ccf1680b7c88f874912b6bec2797b76b authored by Thomas Gleixner on 04 March 2014, 20:43:41 UTC
irqchip: armanda: Sanitize set_irq_affinity()
Tip revision: 8cc3cfc
gcd.c 
#include <linux/kernel.h>
#include <linux/gcd.h>
#include <linux/export.h>

/* Greatest common divisor */
unsigned long gcd(unsigned long a, unsigned long b)
{
	unsigned long r;

	if (a < b)
		swap(a, b);

	if (!b)
		return a;
	while ((r = a % b) != 0) {
		a = b;
		b = r;
	}
	return b;
}
EXPORT_SYMBOL_GPL(gcd);
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