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genirq: Add might_sleep() to disable_irq()

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With the introduction of threaded interrupt handlers, it is virtually
never safe to call disable_irq() from non-premptible context.

Thus: Update the documentation, add an explicit might_sleep() to catch any
offenders. This is more obvious and straight forward than the implicit
might_sleep() check deeper down in the disable_irq() call chain.

Fixes: 3aa551c9b4 ("genirq: add threaded interrupt handler support")
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20221216150441.200533-3-manfred@colorfullife.com
This commit is contained in:
Manfred Spraul 2022-12-16 16:04:41 +01:00 committed by Thomas Gleixner
parent b7bfaa761d
commit 17549b0f18
1 changed files with 4 additions and 1 deletions
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5
kernel/irq/manage.c
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@ -723,10 +723,13 @@ EXPORT_SYMBOL(disable_irq_nosync);
* to complete before returning. If you use this function while
* holding a resource the IRQ handler may need you will deadlock.
*
* This function may be called - with care - from IRQ context.
* Can only be called from preemptible code as it might sleep when
* an interrupt thread is associated to @irq.
*
*/
void disable_irq(unsigned int irq)
{
might_sleep();
if (!__disable_irq_nosync(irq))
synchronize_irq(irq);
}