From d24da1f85530a5b47590c0febd1395dd8fc73124 Mon Sep 17 00:00:00 2001 From: Naveen N Rao Date: Fri, 9 Jun 2023 09:15:01 +0530 Subject: powerpc/ftrace: Disable ftrace on ppc32 if using clang Ftrace on ppc32 expects a three instruction sequence at the beginning of each function when specifying -pg: mflr r0 stw r0,4(r1) bl _mcount This is the case with all supported versions of gcc. Clang however emits a branch to _mcount after the function prologue, similar to the pre -mprofile-kernel ABI on ppc64. This is not supported. Disable ftrace on ppc32 if using clang for now. This can be re-enabled later if clang picks up support for -fpatchable-function-entry on ppc32. Signed-off-by: Naveen N Rao Acked-by: Nick Desaulniers Link: https://github.com/llvm/llvm-project/issues/63220 Signed-off-by: Michael Ellerman Link: https://msgid.link/20230609034501.407971-1-naveen@kernel.org --- arch/powerpc/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/powerpc/Kconfig') diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index dea8e0c7f7e3..8b955bc7b59f 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -236,7 +236,7 @@ config PPC select HAVE_FUNCTION_DESCRIPTORS if PPC64_ELF_ABI_V1 select HAVE_FUNCTION_ERROR_INJECTION select HAVE_FUNCTION_GRAPH_TRACER - select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_TRACER if PPC64 || (PPC32 && CC_IS_GCC) select HAVE_GCC_PLUGINS if GCC_VERSION >= 50200 # plugin support on gcc <= 5.1 is buggy on PPC select HAVE_GENERIC_VDSO select HAVE_HARDLOCKUP_DETECTOR_ARCH if PPC_BOOK3S_64 && SMP -- cgit