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Diffstat (limited to 'arch/x86/kernel/apic/vector.c')
-rw-r--r--arch/x86/kernel/apic/vector.c20
1 files changed, 14 insertions, 6 deletions
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 2c5676b0a6e7..67768e54438b 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -557,6 +557,12 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
irqd->hwirq = virq + i;
irqd_set_single_target(irqd);
/*
+ * Prevent that any of these interrupts is invoked in
+ * non interrupt context via e.g. generic_handle_irq()
+ * as that can corrupt the affinity move state.
+ */
+ irqd_set_handle_enforce_irqctx(irqd);
+ /*
* Legacy vectors are already assigned when the IOAPIC
* takes them over. They stay on the same vector. This is
* required for check_timer() to work correctly as it might
@@ -838,13 +844,15 @@ static void free_moved_vector(struct apic_chip_data *apicd)
bool managed = apicd->is_managed;
/*
- * This should never happen. Managed interrupts are not
- * migrated except on CPU down, which does not involve the
- * cleanup vector. But try to keep the accounting correct
- * nevertheless.
+ * Managed interrupts are usually not migrated away
+ * from an online CPU, but CPU isolation 'managed_irq'
+ * can make that happen.
+ * 1) Activation does not take the isolation into account
+ * to keep the code simple
+ * 2) Migration away from an isolated CPU can happen when
+ * a non-isolated CPU which is in the calculated
+ * affinity mask comes online.
*/
- WARN_ON_ONCE(managed);
-
trace_vector_free_moved(apicd->irq, cpu, vector, managed);
irq_matrix_free(vector_matrix, cpu, vector, managed);
per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;