[PATCH 5.0 082/117] genirq: Initialize request_mutex if CONFIG_SPARSE_IRQ=n

Greg Kroah-Hartman
2019-04-15T19:13:29Z

From: Kefeng Wang <wangkefeng.wang@huawei.com>

commit e8458e7afa855317b14915d7b86ab3caceea7eb6 upstream.

When CONFIG_SPARSE_IRQ is disable, the request_mutex in struct irq_desc
is not initialized which causes malfunction.

Fixes: 9114014cf4e6 ("genirq: Add mutex to irq desc to serialize request/free_irq()")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190404074512.145533-1-wangkefeng.wang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
kernel/irq/irqdesc.c | 1 +
1 file changed, 1 insertion(+)

--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -558,6 +558,7 @@ int __init early_irq_init(void)
alloc_masks(&desc[i], node);
raw_spin_lock_init(&desc[i].lock);
lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
+ mutex_init(&desc[i].request_mutex);
desc_set_defaults(i, &desc[i], node, NULL, NULL);
}
return arch_early_irq_init();