[PATCH net v2 4/4] net: dsa: microchip: Immediately assing IRQ numbers

Bastien Curutchet (Schneider Electric)
2025-11-06T12:53:23Z

The IRQ numbers created through irq_create_mapping() are only assigned
to ptpmsg_irq[n].num at the end of the IRQ setup. So if an error occurs
between their creation and their assignment (for instance during the
request_threaded_irq() step), we enter the error path and fail to
release the newly created virtual IRQs because they aren't yet assigned
to ptpmsg_irq[n].num.

Assign the IRQ number at mapping creation.

Fixes: cc13ab18b201 ("net: dsa: microchip: ptp: enable interrupt for timestamping")
Signed-off-by: Bastien Curutchet (Schneider Electric) <bastien.curutchet@bootlin.com>
---
drivers/net/dsa/microchip/ksz_ptp.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz_ptp.c b/drivers/net/dsa/microchip/ksz_ptp.c
index c8bfbe5e2157323ecf29149d1907b77e689aa221..a8ad99c6ee35ff60fb56cc5770520a793c86ff66 100644
--- a/drivers/net/dsa/microchip/ksz_ptp.c
+++ b/drivers/net/dsa/microchip/ksz_ptp.c
@@ -1102,10 +1102,6 @@ static int ksz_ptp_msg_irq_setup(struct ksz_port *port, u8 n)

strscpy(ptpmsg_irq->name, name[n]);

- ptpmsg_irq->num = irq_find_mapping(port->ptpirq.domain, n);
- if (ptpmsg_irq->num < 0)
- return ptpmsg_irq->num;
-
return request_threaded_irq(ptpmsg_irq->num, NULL,
ksz_ptp_msg_thread_fn, IRQF_ONESHOT,
ptpmsg_irq->name, ptpmsg_irq);
@@ -1135,8 +1131,13 @@ int ksz_ptp_irq_setup(struct dsa_switch *ds, u8 p)
if (!ptpirq->domain)
return -ENOMEM;

- for (irq = 0; irq < ptpirq->nirqs; irq++)
- irq_create_mapping(ptpirq->domain, irq);
+ for (irq = 0; irq < ptpirq->nirqs; irq++) {
+ port->ptpmsg_irq[irq].num = irq_create_mapping(ptpirq->domain, irq);
+ if (!port->ptpmsg_irq[irq].num) {
+ ret = -EINVAL;
+ goto out;
+ }
+ }

ptpirq->irq_num = irq_find_mapping(port->pirq.domain, PORT_SRC_PTP_INT);
if (!ptpirq->irq_num) {

--
2.51.0