Hi Daniel, On 03.10.2022 11:25, Daniel Lezcano wrote: > The generic version of of_thermal_get_crit_temp() can be used. Let's > remove this ops which is pointless. > > Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> This patch breaks Exynos thermal driver as it introduces a NULL pointer dereference in exynos_tmu_initialize(): 8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 [00000000] *pgd=00000000 Internal error: Oops: 80000005 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc1-00072-ge521efddb107 #12941 Hardware name: Samsung Exynos (Flattened Device Tree) dwc2 12480000.hsotg: new address 125 PC is at 0x0 LR is at exynos_tmu_initialize+0x4c/0x1e8 ... Process swapper/0 (pid: 1, stack limit = 0x(ptrval)) Stack: (0xf082dd78 to 0xf082e000) ... exynos_tmu_initialize from exynos_tmu_probe+0x2b0/0x728 exynos_tmu_probe from platform_probe+0x5c/0xb8 platform_probe from really_probe+0xe0/0x414 really_probe from __driver_probe_device+0xa0/0x208 __driver_probe_device from driver_probe_device+0x30/0xc0 driver_probe_device from __driver_attach+0xf0/0x1f0 __driver_attach from bus_for_each_dev+0x70/0xb0 bus_for_each_dev from bus_add_driver+0x174/0x218 bus_add_driver from driver_register+0x88/0x11c driver_register from do_one_initcall+0x64/0x380 do_one_initcall from kernel_init_freeable+0x1c0/0x224 kernel_init_freeable from kernel_init+0x18/0x12c kernel_init from ret_from_fork+0x14/0x2c Exception stack(0xf082dfb0 to 0xf082dff8) ... Code: bad PC value ---[ end trace 0000000000000000 ]--- If there is no replacement for tzd->ops->get_crit_temp(tzd, &temp), then please simply remove that call in exynos_tmu_initialize() to avoid breaking the initialization. > --- > drivers/thermal/thermal_of.c | 15 --------------- > 1 file changed, 15 deletions(-) > > diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c > index 494e9c319541..bd872183e521 100644 > --- a/drivers/thermal/thermal_of.c > +++ b/drivers/thermal/thermal_of.c > @@ -19,20 +19,6 @@ > #include "thermal_core.h" > -static int of_thermal_get_crit_temp(struct thermal_zone_device *tz, > - int *temp) > -{ > - int i; > - > - for (i = 0; i < tz->num_trips; i++) > - if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) { > - *temp = tz->trips[i].temperature; > - return 0; > - } > - > - return -EINVAL; > -} > - > /*** functions parsing device tree nodes ***/ > static int of_find_trip_id(struct device_node *np, struct device_node > *trip) > @@ -529,7 +515,6 @@ struct thermal_zone_device > *thermal_of_zone_register(struct device_node *sensor, > goto out_kfree_trips; > } > - of_ops->get_crit_temp = of_ops->get_crit_temp ? : > of_thermal_get_crit_temp; > of_ops->bind = thermal_of_bind; > of_ops->unbind = thermal_of_unbind; Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland