[tip: x86/urgent] x86/retpoline: Add ANNOTATE_NOENDBR for retpolines

[tip-bot2 for Josh Poimboeuf]

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     1c0513dec41e4d40eb21402dff397ad84ca13a44
Gitweb:        https://git.kernel.org/tip/1c0513dec41e4d40eb21402dff397ad84ca13a44
Author:        Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
AuthorDate:    Mon, 18 Apr 2022 09:50:23 -07:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Tue, 19 Apr 2022 21:58:49 +02:00

x86/retpoline: Add ANNOTATE_NOENDBR for retpolines

The retpolines are exported, so they're referenced by ksymtab sections.
But they're never indirect-branched to, so add ANNOTATE_NOENDBR.

Fixes: ed53a0d97192 ("x86/alternative: Use .ibt_endbr_seal to seal indirect calls")
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/b6ec963dfd9301b6b1d74ef7758fcb0b540d6c6c.1650300597.git.jpoimboe@xxxxxxxxxx
---
 arch/x86/lib/retpoline.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index 5f87bab..b2b2366 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -31,6 +31,7 @@
 	.align RETPOLINE_THUNK_SIZE
 SYM_INNER_LABEL(__x86_indirect_thunk_\reg, SYM_L_GLOBAL)
 	UNWIND_HINT_EMPTY
+	ANNOTATE_NOENDBR
 
 	ALTERNATIVE_2 __stringify(ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), \
 		      __stringify(RETPOLINE \reg), X86_FEATURE_RETPOLINE, \
@@ -55,7 +56,6 @@ SYM_INNER_LABEL(__x86_indirect_thunk_\reg, SYM_L_GLOBAL)
 
 	.align RETPOLINE_THUNK_SIZE
 SYM_CODE_START(__x86_indirect_thunk_array)
-	ANNOTATE_NOENDBR // apply_retpolines
 
 #define GEN(reg) THUNK reg
 #include <asm/GEN-for-each-reg.h>