[tip:x86/pti] x86/speculation: Add RETPOLINE_AMD support to the inline asm CALL_NOSPEC variant

From: tip-bot for Zhenzhong Duan
Date: Mon Sep 24 2018 - 11:06:17 EST


Commit-ID: 0cbb76d6285794f30953bfa3ab831714b59dd700
Gitweb: https://git.kernel.org/tip/0cbb76d6285794f30953bfa3ab831714b59dd700
Author: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxxx>
AuthorDate: Tue, 18 Sep 2018 07:45:00 -0700
Committer: Borislav Petkov <bp@xxxxxxx>
CommitDate: Sun, 23 Sep 2018 15:25:28 +0200

x86/speculation: Add RETPOLINE_AMD support to the inline asm CALL_NOSPEC variant

..so that they match their asm counterpart.

Add the missing ANNOTATE_NOSPEC_ALTERNATIVE in CALL_NOSPEC, while at it.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: David Woodhouse <dwmw@xxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Wang YanQing <udknight@xxxxxxxxx>
Cc: dhaval.giani@xxxxxxxxxx
Cc: srinivas.eeda@xxxxxxxxxx
Link: http://lkml.kernel.org/r/c3975665-173e-4d70-8dee-06c926ac26ee@default
---
arch/x86/include/asm/nospec-branch.h | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index fd2a8c1b88bc..80dc14422495 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -170,11 +170,15 @@
*/
# define CALL_NOSPEC \
ANNOTATE_NOSPEC_ALTERNATIVE \
- ALTERNATIVE( \
+ ALTERNATIVE_2( \
ANNOTATE_RETPOLINE_SAFE \
"call *%[thunk_target]\n", \
"call __x86_indirect_thunk_%V[thunk_target]\n", \
- X86_FEATURE_RETPOLINE)
+ X86_FEATURE_RETPOLINE, \
+ "lfence;\n" \
+ ANNOTATE_RETPOLINE_SAFE \
+ "call *%[thunk_target]\n", \
+ X86_FEATURE_RETPOLINE_AMD)
# define THUNK_TARGET(addr) [thunk_target] "r" (addr)

#elif defined(CONFIG_X86_32) && defined(CONFIG_RETPOLINE)
@@ -184,7 +188,8 @@
* here, anyway.
*/
# define CALL_NOSPEC \
- ALTERNATIVE( \
+ ANNOTATE_NOSPEC_ALTERNATIVE \
+ ALTERNATIVE_2( \
ANNOTATE_RETPOLINE_SAFE \
"call *%[thunk_target]\n", \
" jmp 904f;\n" \
@@ -199,7 +204,11 @@
" ret;\n" \
" .align 16\n" \
"904: call 901b;\n", \
- X86_FEATURE_RETPOLINE)
+ X86_FEATURE_RETPOLINE, \
+ "lfence;\n" \
+ ANNOTATE_RETPOLINE_SAFE \
+ "call *%[thunk_target]\n", \
+ X86_FEATURE_RETPOLINE_AMD)

# define THUNK_TARGET(addr) [thunk_target] "rm" (addr)
#else /* No retpoline for C / inline asm */