Merge tag 'objtool-core-2020-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:
 "Most of the changes are cleanups and reorganization to make the
  objtool code more arch-agnostic. This is in preparation for non-x86
  support.

  Other changes:

   - KASAN fixes

   - Handle unreachable trap after call to noreturn functions better

   - Ignore unreachable fake jumps

   - Misc smaller fixes & cleanups"

* tag 'objtool-core-2020-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  perf build: Allow nested externs to enable BUILD_BUG() usage
  objtool: Allow nested externs to enable BUILD_BUG()
  objtool: Permit __kasan_check_{read,write} under UACCESS
  objtool: Ignore unreachable trap after call to noreturn functions
  objtool: Handle calling non-function symbols in other sections
  objtool: Ignore unreachable fake jumps
  objtool: Remove useless tests before save_reg()
  objtool: Decode unwind hint register depending on architecture
  objtool: Make unwind hint definitions available to other architectures
  objtool: Only include valid definitions depending on source file type
  objtool: Rename frame.h -> objtool.h
  objtool: Refactor jump table code to support other architectures
  objtool: Make relocation in alternative handling arch dependent
  objtool: Abstract alternative special case handling
  objtool: Move macros describing structures to arch-dependent code
  objtool: Make sync-check consider the target architecture
  objtool: Group headers to check in a single list
  objtool: Define 'struct orc_entry' only when needed
  objtool: Skip ORC entry creation for non-text sections
  objtool: Move ORC logic out of check()
  ...

1 files changed, 37 insertions, 0 deletions

diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 1967370440b3..cde9c36e40ae 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -15,6 +15,7 @@
 #include "../../elf.h"
 #include "../../arch.h"
 #include "../../warn.h"
+#include <asm/orc_types.h>
 
 static unsigned char op_to_cfi_reg[][2] = {
 	{CFI_AX, CFI_R8},
@@ -583,3 +584,39 @@ const char *arch_nop_insn(int len)
 
 	return nops[len-1];
 }
+
+int arch_decode_hint_reg(struct instruction *insn, u8 sp_reg)
+{
+	struct cfi_reg *cfa = &insn->cfi.cfa;
+
+	switch (sp_reg) {
+	case ORC_REG_UNDEFINED:
+		cfa->base = CFI_UNDEFINED;
+		break;
+	case ORC_REG_SP:
+		cfa->base = CFI_SP;
+		break;
+	case ORC_REG_BP:
+		cfa->base = CFI_BP;
+		break;
+	case ORC_REG_SP_INDIRECT:
+		cfa->base = CFI_SP_INDIRECT;
+		break;
+	case ORC_REG_R10:
+		cfa->base = CFI_R10;
+		break;
+	case ORC_REG_R13:
+		cfa->base = CFI_R13;
+		break;
+	case ORC_REG_DI:
+		cfa->base = CFI_DI;
+		break;
+	case ORC_REG_DX:
+		cfa->base = CFI_DX;
+		break;
+	default:
+		return -1;
+	}
+
+	return 0;
+}