[v4,08/13] x86/IRQs: correct/tighten vector check in _clear_irq_vector()

Commit Message

Jan Beulich July 16, 2019, 7:42 a.m. UTC

If any particular value was to be checked against, it would need to be
IRQ_VECTOR_UNASSIGNED.

Reported-by: Roger Pau Monné <[e-mail]>

Be more strict though and use valid_irq_vector() instead.

Take the opportunity and also convert local variables to unsigned int.

Signed-off-by: Jan Beulich <[e-mail]>
Reviewed-by: Roger Pau Monné <[e-mail]>
Acked-by: Andrew Cooper <[e-mail]>
---
v2: New.

Patch

--- a/xen/arch/x86/irq.c
+++ b/xen/arch/x86/irq.c
@@ -283,14 +283,13 @@  void destroy_irq(unsigned int irq)
  
  static void _clear_irq_vector(struct irq_desc *desc)
  {
-    unsigned int cpu;
-    int vector, old_vector, irq = desc->irq;
+    unsigned int cpu, old_vector, irq = desc->irq;
+    unsigned int vector = desc->arch.vector;
      cpumask_t tmp_mask;
  
-    BUG_ON(!desc->arch.vector);
+    BUG_ON(!valid_irq_vector(vector));
  
      /* Always clear desc->arch.vector */
-    vector = desc->arch.vector;
      cpumask_and(&tmp_mask, desc->arch.cpu_mask, &cpu_online_map);
  
      for_each_cpu(cpu, &tmp_mask) {