5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Borislav Petkov (AMD)" <bp@xxxxxxxxx> 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@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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) {