From ecb108e3e3f7c692082b7c6fce41779c3835854a Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 18 Oct 2021 15:30:41 +0100 Subject: ARM: 9144/1: forbid ftrace with clang and thumb2_kernel clang fails to build kernels with THUMB2 and FUNCTION_TRACER enabled when there is any inline asm statement containing the frame pointer register r7: arch/arm/mach-exynos/mcpm-exynos.c:154:2: error: inline asm clobber list contains reserved registers: R7 [-Werror,-Winline-asm] arch/arm/probes/kprobes/actions-thumb.c:449:3: error: inline asm clobber list contains reserved registers: R7 [-Werror,-Winline-asm] Apparently gcc should also have warned about this, and the configuration is actually invalid, though there is some disagreement on the bug trackers about this. Link: https://bugs.llvm.org/show_bug.cgi?id=45826 Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94986 Reviewed-by: Nick Desaulniers Signed-off-by: Arnd Bergmann Signed-off-by: Russell King (Oracle) --- arch/arm/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 680920f78fcb..5fdb4a11cda3 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -91,7 +91,7 @@ config ARM select HAVE_FAST_GUP if ARM_LPAE select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL select HAVE_FUNCTION_GRAPH_TRACER if !THUMB2_KERNEL && !CC_IS_CLANG - select HAVE_FUNCTION_TRACER if !XIP_KERNEL + select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !(THUMB2_KERNEL && CC_IS_CLANG) select HAVE_GCC_PLUGINS select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7) select HAVE_IRQ_TIME_ACCOUNTING -- cgit v1.2.3