path: root/kernel/irq/cpuhotplug.c
diff options
authorThomas Gleixner <tglx@linutronix.de>2019-06-28 13:11:49 +0200
committerThomas Gleixner <tglx@linutronix.de>2019-07-03 10:12:28 +0200
commit4001d8e8762f57d418b66e4e668601791900a1dd (patch)
tree8424f1b08fd15896521cbc842571042fe9f242fe /kernel/irq/cpuhotplug.c
parentc8c4076723daca08bf35ccd68f22ea1c6219e207 (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/cpuhotplug.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/irq/cpuhotplug.c b/kernel/irq/cpuhotplug.c
index 5b1072e394b2..6c7ca2e983a5 100644
--- a/kernel/irq/cpuhotplug.c
+++ b/kernel/irq/cpuhotplug.c
@@ -116,7 +116,7 @@ static bool migrate_one_irq(struct irq_desc *desc)
if (irqd_affinity_is_managed(d)) {
- irq_shutdown(desc);
+ irq_shutdown_and_deactivate(desc);
return false;
affinity = cpu_online_mask;