mirror of
https://github.com/torvalds/linux.git
synced 2025-11-01 00:58:39 +02:00
f6d87f4bd2
Impact: preserve user-modified affinities on interrupts
Kumar Galak noticed that commit
1840475676 (genirq: Expose default irq
affinity mask (take 3))
overrides an already set affinity setting across a free /
request_irq(). Happens e.g. with ifdown/ifup of a network device.
Change the logic to mark the affinities as set and keep them
intact. This also fixes the unlocked access to irq_desc in
irq_select_affinity() when called from irq_affinity_proc_write()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
64 lines
1.3 KiB
C
64 lines
1.3 KiB
C
|
|
#include <linux/irq.h>
|
|
|
|
void move_masked_irq(int irq)
|
|
{
|
|
struct irq_desc *desc = irq_to_desc(irq);
|
|
cpumask_t tmp;
|
|
|
|
if (likely(!(desc->status & IRQ_MOVE_PENDING)))
|
|
return;
|
|
|
|
/*
|
|
* Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
|
|
*/
|
|
if (CHECK_IRQ_PER_CPU(desc->status)) {
|
|
WARN_ON(1);
|
|
return;
|
|
}
|
|
|
|
desc->status &= ~IRQ_MOVE_PENDING;
|
|
|
|
if (unlikely(cpus_empty(desc->pending_mask)))
|
|
return;
|
|
|
|
if (!desc->chip->set_affinity)
|
|
return;
|
|
|
|
assert_spin_locked(&desc->lock);
|
|
|
|
cpus_and(tmp, desc->pending_mask, cpu_online_map);
|
|
|
|
/*
|
|
* If there was a valid mask to work with, please
|
|
* do the disable, re-program, enable sequence.
|
|
* This is *not* particularly important for level triggered
|
|
* but in a edge trigger case, we might be setting rte
|
|
* when an active trigger is comming in. This could
|
|
* cause some ioapics to mal-function.
|
|
* Being paranoid i guess!
|
|
*
|
|
* For correct operation this depends on the caller
|
|
* masking the irqs.
|
|
*/
|
|
if (likely(!cpus_empty(tmp))) {
|
|
desc->chip->set_affinity(irq,tmp);
|
|
}
|
|
cpus_clear(desc->pending_mask);
|
|
}
|
|
|
|
void move_native_irq(int irq)
|
|
{
|
|
struct irq_desc *desc = irq_to_desc(irq);
|
|
|
|
if (likely(!(desc->status & IRQ_MOVE_PENDING)))
|
|
return;
|
|
|
|
if (unlikely(desc->status & IRQ_DISABLED))
|
|
return;
|
|
|
|
desc->chip->mask(irq);
|
|
move_masked_irq(irq);
|
|
desc->chip->unmask(irq);
|
|
}
|
|
|