From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Tom Lendacky Date: Wed, 20 Dec 2017 10:55:47 +0000 Subject: [PATCH] x86/microcode: Extend post microcode reload to support IBPB feature MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit CVE-2017-5753 CVE-2017-5715 Add an IBPB feature check to the speculative control update check after a microcode reload. Signed-off-by: Tom Lendacky Signed-off-by: Andy Whitcroft Signed-off-by: Kleber Sacilotto de Souza (cherry picked from commit 099878acd3738271fb2ade01f4649b1ed2fb72d5) Signed-off-by: Fabian Grünbichler --- arch/x86/kernel/cpu/microcode/core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index 55086921d29e..638c08350d65 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -546,6 +546,13 @@ static ssize_t reload_store(struct device *dev, if (ibpb_inuse) sysctl_ibpb_enabled = 1; mutex_unlock(&spec_ctrl_mutex); + } else if (boot_cpu_has(X86_FEATURE_IBPB)) { + printk_once(KERN_INFO "FEATURE IBPB Present\n"); + mutex_lock(&spec_ctrl_mutex); + set_ibpb_supported(); + if (ibpb_inuse) + sysctl_ibpb_enabled = 1; + mutex_unlock(&spec_ctrl_mutex); } mutex_unlock(µcode_mutex); -- 2.14.2