diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2019-06-28 13:11:49 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2019-07-03 10:12:28 +0200 |
| commit | 4001d8e8762f57d418b66e4e668601791900a1dd (patch) | |
| tree | 8424f1b08fd15896521cbc842571042fe9f242fe /kernel/irq/chip.c | |
| parent | c8c4076723daca08bf35ccd68f22ea1c6219e207 (diff) | |
genirq: Delay deactivation in free_irq()
When interrupts are shutdown, they are immediately deactivated in the
irqdomain hierarchy. While this looks obviously correct there is a subtle
issue:
There might be an interrupt in flight when free_irq() is invoking the
shutdown. This is properly handled at the irq descriptor / primary handler
level, but the deactivation might completely disable resources which are
required to acknowledge the interrupt.
Split the shutdown code and deactivate the interrupt after synchronization
in free_irq(). Fixup all other usage sites where this is not an issue to
invoke the combined shutdown_and_deactivate() function instead.
This still might be an issue if the interrupt in flight servicing is
delayed on a remote CPU beyond the invocation of synchronize_irq(), but
that cannot be handled at that level and needs to be handled in the
synchronize_irq() context.
Fixes: f8264e34965a ("irqdomain: Introduce new interfaces to support hierarchy irqdomains")
Reported-by: Robert Hodaszi <Robert.Hodaszi@digi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20190628111440.098196390@linutronix.de
Diffstat (limited to 'kernel/irq/chip.c')
| -rw-r--r-- | kernel/irq/chip.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 51128bea3846..04fe4f989bd8 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -314,6 +314,12 @@ void irq_shutdown(struct irq_desc *desc) } irq_state_clr_started(desc); } +} + + +void irq_shutdown_and_deactivate(struct irq_desc *desc) +{ + irq_shutdown(desc); /* * This must be called even if the interrupt was never started up, * because the activation can happen before the interrupt is |