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| author | Pawan Gupta <pawan.kumar.gupta@linux.intel.com> | 2020-07-16 22:23:59 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-08-21 14:15:15 +0300 |
| commit | 8dfe0e66582c402d122c87d630a0a439bfa1706b (patch) | |
| tree | c57b8b7c2a7391c018bdfdbca742749b45afc556 /Documentation | |
| parent | bff77b49db3ea98fabfbe8efbb89fc54afabb84b (diff) | |
| download | linux-8dfe0e66582c402d122c87d630a0a439bfa1706b.tar.xz | |
x86/bugs/multihit: Fix mitigation reporting when VMX is not in use
[ Upstream commit f29dfa53cc8ae6ad93bae619bcc0bf45cab344f7 ]
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 <nelson.dsouza@linux.intel.com>
Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/0ba029932a816179b9d14a30db38f0f11ef1f166.1594925782.git.pawan.kumar.gupta@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/hw-vuln/multihit.rst | 4 |
1 files changed, 4 insertions, 0 deletions
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 |