[PATCH 5.10 024/130] objtool: Handle per arch retpoline naming

[Greg Kroah-Hartman]

From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

commit 530b4ddd9dd92b263081f5c7786d39a8129c8b2d upstream.

The __x86_indirect_ naming is obviously not generic. Shorten to allow
matching some additional magic names later.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Reviewed-by: Miroslav Benes <mbenes@xxxxxxx>
Link: https://lkml.kernel.org/r/20210326151259.630296706@xxxxxxxxxxxxx
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 tools/objtool/arch.h            |    2 ++
 tools/objtool/arch/x86/decode.c |    5 +++++
 tools/objtool/check.c           |    9 +++++++--
 3 files changed, 14 insertions(+), 2 deletions(-)

--- a/tools/objtool/arch.h
+++ b/tools/objtool/arch.h
@@ -86,4 +86,6 @@ const char *arch_nop_insn(int len);
 
 int arch_decode_hint_reg(struct instruction *insn, u8 sp_reg);
 
+bool arch_is_retpoline(struct symbol *sym);
+
 #endif /* _ARCH_H */
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -620,3 +620,8 @@ int arch_decode_hint_reg(struct instruct
 
 	return 0;
 }
+
+bool arch_is_retpoline(struct symbol *sym)
+{
+	return !strncmp(sym->name, "__x86_indirect_", 15);
+}
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -778,6 +778,11 @@ static int add_ignore_alternatives(struc
 	return 0;
 }
 
+__weak bool arch_is_retpoline(struct symbol *sym)
+{
+	return false;
+}
+
 /*
  * Find the destination instructions for all jumps.
  */
@@ -800,7 +805,7 @@ static int add_jump_destinations(struct
 		} else if (reloc->sym->type == STT_SECTION) {
 			dest_sec = reloc->sym->sec;
 			dest_off = arch_dest_reloc_offset(reloc->addend);
-		} else if (!strncmp(reloc->sym->name, "__x86_indirect_thunk_", 21)) {
+		} else if (arch_is_retpoline(reloc->sym)) {
 			/*
 			 * Retpoline jumps are really dynamic jumps in
 			 * disguise, so convert them accordingly.
@@ -954,7 +959,7 @@ static int add_call_destinations(struct
 				return -1;
 			}
 
-		} else if (!strncmp(reloc->sym->name, "__x86_indirect_thunk_", 21)) {
+		} else if (arch_is_retpoline(reloc->sym)) {
 			/*
 			 * Retpoline calls are really dynamic calls in
 			 * disguise, so convert them accordingly.