4.15-stable review patch. If anyone has any objections, please let me know.
------------------ From: Borislav Petkov <[email protected]> commit 1008c52c09dcb23d93f8e0ea83a6246265d2cce0 upstream. Add a callback function which the microcode loader calls when microcode has been updated to a newer revision. Do the callback only when no error was encountered during loading. Tested-by: Ashok Raj <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Ashok Raj <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arjan van de Ven <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Woodhouse <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/include/asm/processor.h | 1 + arch/x86/kernel/cpu/common.c | 10 ++++++++++ arch/x86/kernel/cpu/microcode/core.c | 8 ++++++-- 3 files changed, 17 insertions(+), 2 deletions(-) --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -969,4 +969,5 @@ bool xen_set_default_idle(void); void stop_this_cpu(void *dummy); void df_debug(struct pt_regs *regs, long error_code); +void microcode_check(void); #endif /* _ASM_X86_PROCESSOR_H */ --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1749,3 +1749,13 @@ static int __init init_cpu_syscore(void) return 0; } core_initcall(init_cpu_syscore); + +/* + * The microcode loader calls this upon late microcode load to recheck features, + * only when microcode has been updated. Caller holds microcode_mutex and CPU + * hotplug lock. + */ +void microcode_check(void) +{ + perf_check_microcode(); +} --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -509,6 +509,7 @@ static ssize_t reload_store(struct devic const char *buf, size_t size) { enum ucode_state tmp_ret = UCODE_OK; + bool do_callback = false; unsigned long val; ssize_t ret = 0; int cpu; @@ -531,10 +532,13 @@ static ssize_t reload_store(struct devic if (!ret) ret = -EINVAL; } + + if (tmp_ret == UCODE_UPDATED) + do_callback = true; } - if (!ret && tmp_ret == UCODE_UPDATED) - perf_check_microcode(); + if (!ret && do_callback) + microcode_check(); mutex_unlock(µcode_mutex); put_online_cpus();
