genirq/msi: Fix populating multiple interrupts

On allocating the interrupts routed via a wire-to-MSI bridge, the allocator
iterates over the MSI descriptors to build the hierarchy, but fails to use
the descriptor interrupt number, and instead uses the base number,
generating the wrong IRQ domain mappings.

The fix is to use the MSI descriptor interrupt number when setting up
the interrupt instead of the base interrupt for the allocation range.

The only saving grace is that although the MSI descriptors are allocated
in bulk, the wired interrupts are only allocated one by one (so
desc->irq == virq) and the bug went unnoticed so far.

Fixes: 2145ac9310 ("genirq/msi: Add msi_domain_populate_irqs")
Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170906103540.373864a2.john@metanate.com
This commit is contained in:
John Keeping 2017-09-06 10:35:40 +01:00 committed by Thomas Gleixner
parent 24e700e291
commit 596a7a1d09

View file

@ -315,11 +315,12 @@ int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
ops->set_desc(arg, desc);
/* Assumes the domain mutex is held! */
ret = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
ret = irq_domain_alloc_irqs_hierarchy(domain, desc->irq, 1,
arg);
if (ret)
break;
irq_set_msi_desc_off(virq, 0, desc);
irq_set_msi_desc_off(desc->irq, 0, desc);
}
if (ret) {