On Wed, Feb 20, 2019 at 09:53:34AM +0100, Borislav Petkov wrote:

On Fri, Jan 18, 2019 at 07:48:59AM -0800, tip-bot for Jiaxun Yang wrote:

...

Commit-ID: 0237199186e7a4aa5310741f0a6498a20c820fd7 Gitweb: https://git.kernel.org/tip/0237199186e7a4aa5310741f0a6498a20c820fd7 Author: Jiaxun Yang jiaxun.yang@flygoat.com AuthorDate: Tue, 20 Nov 2018 11:00:18 +0800 Committer: Borislav Petkov bp@suse.de CommitDate: Fri, 18 Jan 2019 16:44:03 +0100

x86/CPU/AMD: Set the CPB bit unconditionally on F17h

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@flygoat.com Signed-off-by: Borislav Petkov bp@suse.de Acked-by: Tom Lendacky thomas.lendacky@amd.com Cc: "H. Peter Anvin" hpa@zytor.com Cc: Ingo Molnar mingo@redhat.com Cc: Sherry Hurwitz sherry.hurwitz@amd.com Cc: Suravee Suthikulpanit suravee.suthikulpanit@amd.com Cc: Thomas Gleixner tglx@linutronix.de Cc: x86-ml x86@kernel.org Link: https://lkml.kernel.org/r/20181120030018.5185-1-jiaxun.yang@flygoat.com

---

arch/x86/kernel/cpu/amd.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 69f6bbb41be0..01004bfb1a1b 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -819,11 +819,9 @@ static void init_amd_bd(struct cpuinfo_x86 *c) 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);

Stable folks, please take this one above into those stable trees which have backported

f7f3dc00f612 ("x86/cpu/AMD: Fix erratum 1076 (CPB bit)")

I would, but I do not see this patch in Linus's tree yet :)

thanks,

greg k-h