[PATCH] irqchip/gic-v5: Install root IRQ handler last in gicv5_init_common()

[Jiangshan Yi]

set_handle_irq() is irreversible: once installed, handle_arch_irq
points at gicv5_handle_irq, which dereferences the PPI/SPI/LPI
irqdomains.  If gicv5_irs_enable() fails afterwards, the error path
calls gicv5_free_domains() while handle_arch_irq still references
those domains.

Move set_handle_irq() after gicv5_irs_enable() so the handler is
only installed once all fallible steps have succeeded.  Drop the
no-op set_handle_irq(NULL) in the error path, which never worked
because set_handle_irq() returns -EBUSY once a handler is set.

Fixes: 183750b276c2 ("irqchip/gic-v5: Fix gicv5_init_common() error paths")
Signed-off-by: Jiangshan Yi <yijiangshan at kylinos.cn>
---
 drivers/irqchip/irq-gic-v5.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v5.c b/drivers/irqchip/irq-gic-v5.c
index ac2d423b1723..37184942dc11 100644
--- a/drivers/irqchip/irq-gic-v5.c
+++ b/drivers/irqchip/irq-gic-v5.c
@@ -1166,21 +1166,19 @@ static int __init gicv5_init_common(struct fwnode_handle *parent_domain)
 	if (ret)
 		goto out_int;
 
-	ret = set_handle_irq(gicv5_handle_irq);
+	ret = gicv5_irs_enable();
 	if (ret)
 		goto out_int;
 
-	ret = gicv5_irs_enable();
+	ret = set_handle_irq(gicv5_handle_irq);
 	if (ret)
-		goto out_handle;
+		goto out_int;
 
 	gicv5_smp_init();
 
 	gicv5_irs_its_probe();
 	return 0;
 
-out_handle:
-	set_handle_irq(NULL);
 out_int:
 	gicv5_cpu_disable_interrupts();
 	gicv5_free_domains();
-- 
2.25.1