5.10-stable review patch. If anyone has any objections, please let me know.
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From: "Borislav Petkov (AMD)" bp@alien8.de
This reverts commit 08f7cfd44f77b2796582bc26164fdef44dd33b6c.
Revert the backport of upstream commit:
095b8303f383 ("x86/alternative: Make custom return thunk unconditional")
in order to backport the full version now that
770ae1b70952 ("x86/returnthunk: Allow different return thunks")
has been backported.
Revert it here so that the build breakage is kept at minimum.
Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/include/asm/nospec-branch.h | 4 ---- arch/x86/kernel/cpu/bugs.c | 4 ---- 2 files changed, 8 deletions(-)
--- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -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); --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -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) {