[PATCH 4.9 241/264] irqchip/gic-v3: Iterate over possible CPUs by for_each_possible_cpu()

Greg Kroah-Hartman
2022-06-23T17:11:39Z

From: zijun_hu <zijun_hu@htc.com>

[ Upstream commit 3fad4cdac235c5b13227d0c09854c689ae62c70b ]

get_cpu_number() doesn't use existing helper to iterate over possible
CPUs, It will cause an error in case of discontinuous @cpu_possible_mask
such as 0b11110001, which can result from a core having failed to come
up on a SMP machine.

Fixed by using existing helper for_each_possible_cpu().

Signed-off-by: zijun_hu <zijun_hu@htc.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/irqchip/irq-gic-v3.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 2ab6060031a4..9ae24ffb9b09 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -982,7 +982,7 @@ static int get_cpu_number(struct device_node *dn)
{
const __be32 *cell;
u64 hwid;
- int i;
+ int cpu;

cell = of_get_property(dn, "reg", NULL);
if (!cell)
@@ -996,9 +996,9 @@ static int get_cpu_number(struct device_node *dn)
if (hwid & ~MPIDR_HWID_BITMASK)
return -1;

- for (i = 0; i < num_possible_cpus(); i++)
- if (cpu_logical_map(i) == hwid)
- return i;
+ for_each_possible_cpu(cpu)
+ if (cpu_logical_map(cpu) == hwid)
+ return cpu;

return -1;
}
--
2.35.1