[PATCH 6.7 114/162] pmdomain: arm: Fix NULL dereference on scmi_perf_domain removal

Greg Kroah-Hartman
2024-03-04T21:30:52Z

From: Cristian Marussi <cristian.marussi@arm.com>

commit eb5555d422d0fc325e1574a7353d3c616f82d8b5 upstream.

On unloading of the scmi_perf_domain module got the below splat, when in
the DT provided to the system under test the '#power-domain-cells' property
was missing. Indeed, this particular setup causes the probe to bail out
early without giving any error, which leads to the ->remove() callback gets
to run too, but without all the expected initialized structures in place.

Add a check and bail out early on remove too.

Call trace:
scmi_perf_domain_remove+0x28/0x70 [scmi_perf_domain]
scmi_dev_remove+0x28/0x40 [scmi_core]
device_remove+0x54/0x90
device_release_driver_internal+0x1dc/0x240
driver_detach+0x58/0xa8
bus_remove_driver+0x78/0x108
driver_unregister+0x38/0x70
scmi_driver_unregister+0x28/0x180 [scmi_core]
scmi_perf_domain_driver_exit+0x18/0xb78 [scmi_perf_domain]
__arm64_sys_delete_module+0x1a8/0x2c0
invoke_syscall+0x50/0x128
el0_svc_common.constprop.0+0x48/0xf0
do_el0_svc+0x24/0x38
el0_svc+0x34/0xb8
el0t_64_sync_handler+0x100/0x130
el0t_64_sync+0x190/0x198
Code: a90153f3 f9403c14 f9414800 955f8a05 (b9400a80)
---[ end trace 0000000000000000 ]---

Fixes: 2af23ceb8624 ("pmdomain: arm: Add the SCMI performance domain")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240125191756.868860-1-cristian.marussi@arm.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/pmdomain/arm/scmi_perf_domain.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/pmdomain/arm/scmi_perf_domain.c b/drivers/pmdomain/arm/scmi_perf_domain.c
index 709bbc448fad..d7ef46ccd9b8 100644
--- a/drivers/pmdomain/arm/scmi_perf_domain.c
+++ b/drivers/pmdomain/arm/scmi_perf_domain.c
@@ -159,6 +159,9 @@ static void scmi_perf_domain_remove(struct scmi_device *sdev)
struct genpd_onecell_data *scmi_pd_data = dev_get_drvdata(dev);
int i;

+ if (!scmi_pd_data)
+ return;
+
of_genpd_del_provider(dev->of_node);

for (i = 0; i < scmi_pd_data->num_domains; i++)
--
2.44.0