[PATCH] irqchip/loongson-htvec:- Handle return value of ioremap.

[zhaoxiao]

From: zhaoxiao <zhaoxiao@xxxxxxxxxxxxx>

Here, If ioremap will fail. It will return NULL.Kernel can run into
a NULL-pointer dereference. This error check will avoid NULL pointer
dereference.

Signed-off-by: zhaoxiao <zhaoxiao@xxxxxxxxxxxxx>
---
 drivers/irqchip/irq-loongson-htvec.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/irqchip/irq-loongson-htvec.c b/drivers/irqchip/irq-loongson-htvec.c
index 1cc0bceb4472..a36c20f44ec4 100644
--- a/drivers/irqchip/irq-loongson-htvec.c
+++ b/drivers/irqchip/irq-loongson-htvec.c
@@ -267,6 +267,8 @@ struct fwnode_handle *htvec_acpi_init(struct fwnode_handle *parent,
 
 	priv->num_parents = HTVEC_MAX_PARENT_IRQ;
 	priv->base = ioremap(acpi_htvec->address, acpi_htvec->size);
+	if (!priv->base)
+		goto free_priv;
 
 	/* Interrupt may come from any of the 8 interrupt lines */
 	for (i = 0; i < priv->num_parents; i++)
@@ -307,6 +309,7 @@ struct fwnode_handle *htvec_acpi_init(struct fwnode_handle *parent,
 iounmap_base:
 	iounmap(priv->base);
 	priv->domain_handle = NULL;
+free_priv:
 	kfree(priv);
 
 	return NULL;
-- 
2.20.1