4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx> commit 0237199186e7a4aa5310741f0a6498a20c820fd7 upstream. Some F17h models do not have CPB set in CPUID even though the CPU supports it. Set the feature bit unconditionally on all F17h. [ bp: Rewrite commit message and patch. ] Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Acked-by: Tom Lendacky <thomas.lendacky@xxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Sherry Hurwitz <sherry.hurwitz@xxxxxxx> Cc: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: x86-ml <x86@xxxxxxxxxx> Link: https://lkml.kernel.org/r/20181120030018.5185-1-jiaxun.yang@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/cpu/amd.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -818,11 +818,9 @@ static void init_amd_bd(struct cpuinfo_x static void init_amd_zn(struct cpuinfo_x86 *c) { set_cpu_cap(c, X86_FEATURE_ZEN); - /* - * Fix erratum 1076: CPB feature bit not being set in CPUID. It affects - * all up to and including B1. - */ - if (c->x86_model <= 1 && c->x86_stepping <= 1) + + /* Fix erratum 1076: CPB feature bit not being set in CPUID. */ + if (!cpu_has(c, X86_FEATURE_CPB)) set_cpu_cap(c, X86_FEATURE_CPB); }
