From f29dfa53cc8ae6ad93bae619bcc0bf45cab344f7 Mon Sep 17 00:00:00 2001 From: Pawan Gupta Date: Thu, 16 Jul 2020 12:23:59 -0700 Subject: x86/bugs/multihit: Fix mitigation reporting when VMX is not in use On systems that have virtualization disabled or unsupported, sysfs mitigation for X86_BUG_ITLB_MULTIHIT is reported incorrectly as: $ cat /sys/devices/system/cpu/vulnerabilities/itlb_multihit KVM: Vulnerable System is not vulnerable to DoS attack from a rogue guest when virtualization is disabled or unsupported in the hardware. Change the mitigation reporting for these cases. Fixes: b8e8c8303ff2 ("kvm: mmu: ITLB_MULTIHIT mitigation") Reported-by: Nelson Dsouza Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson Signed-off-by: Pawan Gupta Signed-off-by: Ingo Molnar Reviewed-by: Tony Luck Acked-by: Thomas Gleixner Link: https://lore.kernel.org/r/0ba029932a816179b9d14a30db38f0f11ef1f166.1594925782.git.pawan.kumar.gupta@linux.intel.com --- Documentation/admin-guide/hw-vuln/multihit.rst | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation/admin-guide') diff --git a/Documentation/admin-guide/hw-vuln/multihit.rst b/Documentation/admin-guide/hw-vuln/multihit.rst index ba9988d8bce5..140e4cec38c3 100644 --- a/Documentation/admin-guide/hw-vuln/multihit.rst +++ b/Documentation/admin-guide/hw-vuln/multihit.rst @@ -80,6 +80,10 @@ The possible values in this file are: - The processor is not vulnerable. * - KVM: Mitigation: Split huge pages - Software changes mitigate this issue. + * - KVM: Mitigation: VMX unsupported + - KVM is not vulnerable because Virtual Machine Extensions (VMX) is not supported. + * - KVM: Mitigation: VMX disabled + - KVM is not vulnerable because Virtual Machine Extensions (VMX) is disabled. * - KVM: Vulnerable - The processor is vulnerable, but no mitigation enabled -- cgit