arch_smt_update() will be used to control IPI/NMI broadcasting via the shorthand mechanism. Keeping it in the bugs file and calling the apic function from there is possible, but not really intuitive.
Move it to a neutral place and invoke the bugs function from there. No functional change. Signed-off-by: Thomas Gleixner <t...@linutronix.de> --- arch/x86/include/asm/bugs.h | 2 ++ arch/x86/kernel/cpu/bugs.c | 2 +- arch/x86/kernel/cpu/common.c | 9 +++++++++ 3 files changed, 12 insertions(+), 1 deletion(-) --- a/arch/x86/include/asm/bugs.h +++ b/arch/x86/include/asm/bugs.h @@ -18,4 +18,6 @@ int ppro_with_ram_bug(void); static inline int ppro_with_ram_bug(void) { return 0; } #endif +extern void cpu_bugs_smt_update(void); + #endif /* _ASM_X86_BUGS_H */ --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -700,7 +700,7 @@ static void update_mds_branch_idle(void) #define MDS_MSG_SMT "MDS CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html for more details.\n" -void arch_smt_update(void) +void cpu_bugs_smt_update(void) { /* Enhanced IBRS implies STIBP. No update required. */ if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED) --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1880,3 +1880,12 @@ void microcode_check(void) pr_warn("x86/CPU: CPU features have changed after loading microcode, but might not take effect.\n"); pr_warn("x86/CPU: Please consider either early loading through initrd/built-in or a potential BIOS update.\n"); } + +/* + * Invoked from core CPU hotplug code after hotplug operations + */ +void arch_smt_update(void) +{ + /* Handle the speculative execution misfeatures */ + cpu_bugs_smt_update(); +}