From 1edb7e74a7d3d64dc4e69e7059b4eea526d19a10 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 17 Nov 2021 11:35:32 +0000 Subject: clocksource/drivers/arm_arch_timer: Force inlining of erratum_set_next_event_generic() With some specific kernel configuration and Clang, the kernel fails to like with something like: ld.lld: error: undefined symbol: __compiletime_assert_200 >>> referenced by arch_timer.h:156 (./arch/arm64/include/asm/arch_timer.h:156) >>> clocksource/arm_arch_timer.o:(erratum_set_next_event_generic) in archive drivers/built-in.a ld.lld: error: undefined symbol: __compiletime_assert_197 >>> referenced by arch_timer.h:133 (./arch/arm64/include/asm/arch_timer.h:133) >>> clocksource/arm_arch_timer.o:(erratum_set_next_event_generic) in archive drivers/built-in.a make: *** [Makefile:1161: vmlinux] Error 1 These are due to the BUILD_BUG() macros contained in the low-level accessors (arch_timer_reg_{write,read}_cp15) being emitted, as the access type wasn't known at compile time. Fix this by making erratum_set_next_event_generic() __force_inline, resulting in the 'access' parameter to be resolved at compile time, similarly to what is already done for set_next_event(). Fixes: 4775bc63f880 ("Add build-time guards for unhandled register accesses") Reported-by: Greg Kroah-Hartman Signed-off-by: Marc Zyngier Cc: Mark Rutland Cc: Daniel Lezcano Cc: Sami Tolvanen Cc: Nick Desaulniers Tested-by: Sami Tolvanen Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor Link: https://lore.kernel.org/r/20211117113532.3895208-1-maz@kernel.org Signed-off-by: Daniel Lezcano --- drivers/clocksource/arm_arch_timer.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 9a04eacc4412..1ecd52f903b8 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -394,8 +394,13 @@ EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround); static atomic_t timer_unstable_counter_workaround_in_use = ATOMIC_INIT(0); -static void erratum_set_next_event_generic(const int access, unsigned long evt, - struct clock_event_device *clk) +/* + * Force the inlining of this function so that the register accesses + * can be themselves correctly inlined. + */ +static __always_inline +void erratum_set_next_event_generic(const int access, unsigned long evt, + struct clock_event_device *clk) { unsigned long ctrl; u64 cval; -- cgit