This is a note to let you know that I've just added the patch titled
x86/retpoline: Remove the esp/rsp thunk
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-retpoline-remove-the-esp-rsp-thunk.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Wed Feb 7 19:38:23 CST 2018
From: Waiman Long <longman@xxxxxxxxxx>
Date: Mon, 22 Jan 2018 17:09:34 -0500
Subject: x86/retpoline: Remove the esp/rsp thunk
From: Waiman Long <longman@xxxxxxxxxx>
(cherry picked from commit 1df37383a8aeabb9b418698f0bcdffea01f4b1b2)
It doesn't make sense to have an indirect call thunk with esp/rsp as
retpoline code won't work correctly with the stack pointer register.
Removing it will help compiler writers to catch error in case such
a thunk call is emitted incorrectly.
Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support")
Suggested-by: Jeff Law <law@xxxxxxxxxx>
Signed-off-by: Waiman Long <longman@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Jiri Kosina <jikos@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxxx>
Cc: Paul Turner <pjt@xxxxxxxxxx>
Link: https://lkml.kernel.org/r/1516658974-27852-1-git-send-email-longman@xxxxxxxxxx
Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/asm-prototypes.h | 1 -
arch/x86/lib/retpoline.S | 1 -
2 files changed, 2 deletions(-)
--- a/arch/x86/include/asm/asm-prototypes.h
+++ b/arch/x86/include/asm/asm-prototypes.h
@@ -37,5 +37,4 @@ INDIRECT_THUNK(dx)
INDIRECT_THUNK(si)
INDIRECT_THUNK(di)
INDIRECT_THUNK(bp)
-INDIRECT_THUNK(sp)
#endif /* CONFIG_RETPOLINE */
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -36,7 +36,6 @@ GENERATE_THUNK(_ASM_DX)
GENERATE_THUNK(_ASM_SI)
GENERATE_THUNK(_ASM_DI)
GENERATE_THUNK(_ASM_BP)
-GENERATE_THUNK(_ASM_SP)
#ifdef CONFIG_64BIT
GENERATE_THUNK(r8)
GENERATE_THUNK(r9)
Patches currently in stable-queue which might be from longman@xxxxxxxxxx are
queue-4.9/x86-retpoline-remove-the-esp-rsp-thunk.patch