From: Nathan Chancellor <nathan@xxxxxxxxxx>
commit 45be2ad007a9c6bea70249c4cf3e4905afe4caeb upstream.
Recently, ld.lld moved from '--undefined-version' to
'--no-undefined-version' as the default, which breaks building the vDSO
when CONFIG_X86_SGX is not set:
ld.lld: error: version script assignment of 'LINUX_2.6' to symbol '__vdso_sgx_enter_enclave' failed: symbol not defined
__vdso_sgx_enter_enclave is only included in the vDSO when
CONFIG_X86_SGX is set. Only export it if it will be present in the final
object, which clears up the error.
Fixes: 8466436952017 ("x86/vdso: Implement a vDSO for Intel SGX enclave call")
Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Link: https://github.com/ClangBuiltLinux/linux/issues/1756
Link: https://lore.kernel.org/r/20221109000306.1407357-1-nathan@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/entry/vdso/vdso.lds.S | 2 ++
1 file changed, 2 insertions(+)
--- a/arch/x86/entry/vdso/vdso.lds.S
+++ b/arch/x86/entry/vdso/vdso.lds.S
@@ -27,7 +27,9 @@ VERSION {
__vdso_time;
clock_getres;
__vdso_clock_getres;
+#ifdef CONFIG_X86_SGX
__vdso_sgx_enter_enclave;
+#endif
local: *;
};
}
