Commit 0a1058b1 authored by Borislav Petkov (AMD)'s avatar Borislav Petkov (AMD) Committed by sanglipeng1
Browse files

Revert "x86/alternative: Make custom return thunk unconditional" 

stable inclusion
from stable-v5.10.211
commit dd1a169b4496afea2a7a4f841cdad236ef322e6c
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IAF2J4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=dd1a169b4496afea2a7a4f841cdad236ef322e6c



--------------------------------

This reverts commit 08f7cfd44f77b2796582bc26164fdef44dd33b6c.

Revert the backport of upstream commit:

  095b8303 ("x86/alternative: Make custom return thunk unconditional")

in order to backport the full version now that

  770ae1b7 ("x86/returnthunk: Allow different return thunks")

has been backported.

Revert it here so that the build breakage is kept at minimum.

Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarsanglipeng1 <sanglipeng1@jd.com>
parent 9754bf04

arch/x86/include/asm/nospec-branch.h

+0 −4
Original line number Diff line number Diff line
@@ -190,11 +190,7 @@ 
	_ASM_PTR " 999b\n\t"					\

	".popsection\n\t"



#ifdef CONFIG_RETHUNK

extern void __x86_return_thunk(void);

#else

static inline void __x86_return_thunk(void) {}

#endif



extern void retbleed_return_thunk(void);

extern void srso_return_thunk(void);

arch/x86/kernel/cpu/bugs.c

+0 −4
Original line number Diff line number Diff line
@@ -61,10 +61,6 @@ EXPORT_SYMBOL_GPL(x86_pred_cmd); 


static DEFINE_MUTEX(spec_ctrl_mutex);



#ifdef CONFIG_CALL_THUNKS

void (*x86_return_thunk)(void) __ro_after_init = &__x86_return_thunk;

#endif



/* Update SPEC_CTRL MSR and its cached copy unconditionally */

static void update_spec_ctrl(u64 val)

{