Re: [PATCH] clocksource/drivers/exynos_mct: Fix section mismatch from the module conversion
From: "Arnd Bergmann" <arnd@arndb.de>
Date: 2025-07-18 09:53:27
Also in:
linux-samsung-soc, lkml
On Tue, Jul 15, 2025, at 14:18, Daniel Lezcano wrote:
quoted hunk ↗ jump to hunk
diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c index 5075ebe052a7..80d263ee046d 100644 --- a/drivers/clocksource/exynos_mct.c +++ b/drivers/clocksource/exynos_mct.c@@ -657,7 +657,7 @@ static int exynos4_timer_interrupts(struct device_node *np, return err; } -static int mct_init_dt(struct device_node *np, unsigned int int_type) +static __init_or_module int mct_init_dt(struct device_node *np,unsigned int int_type) { bool frc_shared = of_property_read_bool(np, "samsung,frc-shared"); u32 local_idx[MCT_NR_LOCAL] = {0};
Something still feels off here, though I'm not sure what the best
solution would be. Some observations:
- The exynos4_mct_probe() function is listed as permanent, but
it indirectly calls an __init_or_module function, which is not
technically allowed but does not produce a warning here
because of the indirection.
- if the driver is built-in and the platform_driver picks
up the device, it can be manually unbound and rebound, but the
mct_init_dt() will be discarded at this point.
- In a loadable module, you cannot call register_current_timer_delay(),
since this causes a link failure.
- unloading the module fails to undo the registration, so the
next call to delay(), sched_clock(), ktime_get() or an interrupt
ends up in invalid memory.
I think the driver should use an explicit init function calling
platform_driver_probe(), so the probe is only done at initcall
time and both unbinding and unloading are prevented.
Arnd