net: sparx5: skip ptp deinit if init was skipped

sparx5_ptp_init() returns early on the base lan969x variants
because they do not have the SPX5_FEATURE_PTP flag. It also returns early
when no "ptp" interrupt is described. Unbinding the driver then causes a
NULL pointer dereference when cleaning up uninitialized tx_skbs queues:

    Unable to handle kernel NULL pointer dereference at virtual address
    0000000000000008
    Call trace:
    skb_queue_purge_reason+0x68/0x120 (P)
    sparx5_ptp_deinit+0x64/0xc0
    mchp_sparx5_remove+0x38/0x70
    platform_remove+0x20/0x30
    device_remove+0x4c/0x80

Before per-port tx_skbs were added, a NULL dereference would have happened
when calling ptp_clock_unregister() on the never-registered PTP clocks.

Fix by returning early in sparx5_ptp_deinit() if PTP is not used.

Fixes: 0933bd0404 ("net: sparx5: Add support for ptp clocks")
Signed-off-by: Quentin Freimanis <quentin@q-lab.dev>
Reviewed-by: Daniel Machon <daniel.machon@microchip.com>
Link: https://patch.msgid.link/20260928044542.29287-1-quentin@q-lab.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Quentin Freimanis 2026-09-27 21:45:42 -07:00 committed by Jakub Kicinski
parent 20f3599d85
commit 0d2c49915b

View File

@ -673,6 +673,9 @@ void sparx5_ptp_deinit(struct sparx5 *sparx5)
struct sparx5_port *port;
int i;
if (!sparx5->ptp)
return;
if (sparx5->ptp_irq >= 0) {
disable_irq(sparx5->ptp_irq);
sparx5->ptp_irq = -ENXIO;