+From 5462db3d070845ecc34929b6f25a87efda023aae Mon Sep 17 00:00:00 2001
+From: Tom Lendacky <thomas.lendacky@amd.com>
+Date: Tue, 26 Dec 2017 23:43:54 -0600
+Subject: [PATCH 240/241] x86/cpu, x86/pti: Do not enable PTI on AMD processors
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+CVE-2017-5754
+
+AMD processors are not subject to the types of attacks that the kernel
+page table isolation feature protects against. The AMD microarchitecture
+does not allow memory references, including speculative references, that
+access higher privileged data when running in a lesser privileged mode
+when that access would result in a page fault.
+
+Disable page table isolation by default on AMD processors by not setting
+the X86_BUG_CPU_INSECURE feature, which controls whether X86_FEATURE_PTI
+is set.
+
+Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+Reviewed-by: Borislav Petkov <bp@suse.de>
+Cc: Dave Hansen <dave.hansen@linux.intel.com>
+Cc: Andy Lutomirski <luto@kernel.org>
+Cc: stable@vger.kernel.org
+Link: https://lkml.kernel.org/r/20171227054354.20369.94587.stgit@tlendack-t1.amdoffice.net
+
+(cherry picked from commit 694d99d40972f12e59a3696effee8a376b79d7c8)
+Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>
+(cherry picked from commit 9d334f48f017b9c6457c6ba321e5a53a1cc6a5c7)
+Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
+---
+ arch/x86/kernel/cpu/common.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
+index 99f37d1636ff..1854dd8071a6 100644
+--- a/arch/x86/kernel/cpu/common.c
++++ b/arch/x86/kernel/cpu/common.c
+@@ -899,8 +899,8 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
+
+ setup_force_cpu_cap(X86_FEATURE_ALWAYS);
+
+- /* Assume for now that ALL x86 CPUs are insecure */
+- setup_force_cpu_bug(X86_BUG_CPU_INSECURE);
++ if (c->x86_vendor != X86_VENDOR_AMD)
++ setup_force_cpu_bug(X86_BUG_CPU_INSECURE);
+
+ fpu__init_system(c);
+ }
+--
+2.14.2
+