From: Jan Beulich <jbeulich@suse.com>
Date: Mon, 22 Jul 2019 09:45:28 +0000 (+0200)
Subject: x86/IRQs: correct/tighten vector check in _clear_irq_vector()
X-Git-Tag: archive/raspbian/4.14.0+80-gd101b417b7-1+rpi1^2~63^2~1883
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=c6b0dad9345ee6935170cd39a28f0cfdcd7c5b91;p=xen.git

x86/IRQs: correct/tighten vector check in _clear_irq_vector()

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

Reported-by: Roger Pau Monné <roger.pau@citrix.com>

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 <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
---

diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c
index 732ddd4efd..f5e31a1c9b 100644
--- 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) {