When building with clang + CONFIG_CFI_CLANG=y, the following error occurs at link time: ld.lld: error: undefined symbol: dummy_tramp dummy_tramp is declared globally in C but its definition in inline assembly does not use .global, which prevents clang from properly resolving the references to it when creating the CFI jump tables. Mark dummy_tramp as global so that the reference can be properly resolved. Fixes: b2ad54e1533e ("bpf, arm64: Implement bpf_arch_text_poke() for arm64") Link: https://github.com/ClangBuiltLinux/linux/issues/1661 Suggested-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> --- arch/arm64/net/bpf_jit_comp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index fd1cb0d2aaa6..dcc572b7d4da 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -604,6 +604,7 @@ void dummy_tramp(void); asm ( " .pushsection .text, \"ax\", @progbits\n" +" .global dummy_tramp\n" " .type dummy_tramp, %function\n" "dummy_tramp:" #if IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) base-commit: ace2bee839e08df324cb320763258dfd72e6120e -- 2.37.1