From 169f8997968ab620d750d9a45e15c5288d498356 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Wed, 26 Apr 2023 15:58:39 +1000 Subject: powerpc/64s: Disable pcrel code model on Clang Clang has a bug that casues the pcrel code model not to be used when any of -msoft-float, -mno-altivec, or -mno-vsx are set. Leaving these off causes FP/vector instructions to be generated, causing crashes. So disable pcrel for clang for now. Fixes: 7e3a68be42e10 ("powerpc/64: vmlinux support building with PCREL addresing") Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://msgid.link/20230426055848.402993-3-npiggin@gmail.com --- arch/powerpc/Kconfig | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 7a0f25a09759..520e577f3106 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -8,7 +8,12 @@ config CC_HAS_PREFIXED def_bool PPC64 && $(cc-option, -mcpu=power10 -mprefixed) config CC_HAS_PCREL - def_bool PPC64 && $(cc-option, -mcpu=power10 -mpcrel) + # Clang has a bug (https://github.com/llvm/llvm-project/issues/62372) + # where pcrel code is not generated if -msoft-float, -mno-altivec, or + # -mno-vsx options are also given. Without these options, fp/vec + # instructions are generated from regular kernel code. So Clang can't + # do pcrel yet. + def_bool PPC64 && CC_IS_GCC && $(cc-option, -mcpu=power10 -mpcrel) config 32BIT bool -- cgit