xen/smp: unbind irqworkX when unplugging vCPUs.

The git commit  1ff2b0c303698e486f1e0886b4d9876200ef8ca5
"xen: implement IRQ_WORK_VECTOR handler" added the functionality
to have a per-cpu "irqworkX" for the IPI APIC functionality.
However it missed the unbind when a vCPU is unplugged resulting
in an orphaned per-cpu interrupt line for unplugged vCPU:

  30:        216          0   xen-dyn-event     hvc_console
  31:        810          4   xen-dyn-event     eth0
  32:         29          0   xen-dyn-event     blkif
- 36:          0          0  xen-percpu-ipi       irqwork2
- 37:        287          0   xen-dyn-event     xenbus
+ 36:        287          0   xen-dyn-event     xenbus
 NMI:          0          0   Non-maskable interrupts
 LOC:          0          0   Local timer interrupts
 SPU:          0          0   Spurious interrupts

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 3ec3f8eb19fc7ac938b23fd1502f925cbce88b3e..ce9e98b1e69caa2f61ef8227a4f01e6dd5acbcd0 100644 (file)
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -419,6 +419,7 @@ static void xen_cpu_die(unsigned int cpu)
        unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
        unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
        unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL);
+       unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL);
        xen_uninit_lock_cpu(cpu);
        xen_teardown_timer(cpu);