Commit 90af9514 authored by Ian Campbell's avatar Ian Campbell Committed by Ingo Molnar
Browse files

xen: explicitly initialise the cpu field of irq_info 



I was seeing a very odd crash on 64 bit in bind_evtchn_to_cpu because
cpu_from_irq(irq) was coming out as -1. I found this was coming direct
from the mk_ipi_info call.

It's not clear to me that this isn't a compiler bug (implicit
initialisation to zero of unsigned shorts in a struct not handled
correctly?).

On the other hand is it true that all event channels start of bound to
CPU 0? If not then -1 might be correct and the various other functions
should cope with this.

Signed-off-by: default avatarIan Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 3445a8fd

drivers/xen/events.c

+6 −5
Original line number Diff line number Diff line
@@ -115,26 +115,27 @@ static struct irq_info mk_unbound_info(void) 


static struct irq_info mk_evtchn_info(unsigned short evtchn)

{

	return (struct irq_info) { .type = IRQT_EVTCHN, .evtchn = evtchn };

	return (struct irq_info) { .type = IRQT_EVTCHN, .evtchn = evtchn,

			.cpu = 0 };

}



static struct irq_info mk_ipi_info(unsigned short evtchn, enum ipi_vector ipi)

{

	return (struct irq_info) { .type = IRQT_IPI, .evtchn = evtchn,

			.u.ipi = ipi };

			.cpu = 0, .u.ipi = ipi };

}



static struct irq_info mk_virq_info(unsigned short evtchn, unsigned short virq)

{

	return (struct irq_info) { .type = IRQT_VIRQ, .evtchn = evtchn,

			.u.virq = virq };

			.cpu = 0, .u.virq = virq };

}



static struct irq_info mk_pirq_info(unsigned short evtchn,

				    unsigned short gsi, unsigned short vector)

{

	return (struct irq_info) { .type = IRQT_PIRQ, .evtchn = evtchn,

			.u.pirq = { .gsi = gsi, .vector = vector } };

			.cpu = 0, .u.pirq = { .gsi = gsi, .vector = vector } };

}



/*
@@ -375,6 +376,7 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) 
	spin_lock(&irq_mapping_update_lock);



	irq = per_cpu(ipi_to_irq, cpu)[ipi];



	if (irq == -1) {

		irq = find_unbound_irq();

		if (irq < 0)
@@ -391,7 +393,6 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) 


		evtchn_to_irq[evtchn] = irq;

		irq_info[irq] = mk_ipi_info(evtchn, ipi);



		per_cpu(ipi_to_irq, cpu)[ipi] = irq;



		bind_evtchn_to_cpu(evtchn, cpu);

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