Oliver Upton 66570e966d kvm: x86: only provide PV features if enabled in guest's CPUID ... KVM unconditionally provides PV features to the guest, regardless of the configured CPUID. An unwitting guest that doesn't check KVM_CPUID_FEATURES before use could access paravirt features that userspace did not intend to provide. Fix this by checking the guest's CPUID before performing any paravirtual operations. Introduce a capability, KVM_CAP_ENFORCE_PV_FEATURE_CPUID, to gate the aforementioned enforcement. Migrating a VM from a host w/o this patch to a host with this patch could silently change the ABI exposed to the guest, warranting that we default to the old behavior and opt-in for the new one. Reviewed-by: Jim Mattson <jmattson@google.com> Reviewed-by: Peter Shier <pshier@google.com> Signed-off-by: Oliver Upton <oupton@google.com> Change-Id: I202a0926f65035b872bfe8ad15307c026de59a98 Message-Id: <20200818152429.1923996-4-oupton@google.com> Reviewed-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>		2020-10-21 17:36:32 -04:00
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kvm	kvm: x86: only provide PV features if enabled in guest's CPUID	2020-10-21 17:36:32 -04:00
uml	docs: virt: user_mode_linux.rst: fix URL references	2020-02-12 20:09:49 +01:00
guest-halt-polling.rst	docs: virt: guest-halt-polling.txt convert to ReST	2020-02-12 20:10:08 +01:00
index.rst	docs: virt: guest-halt-polling.txt convert to ReST	2020-02-12 20:10:08 +01:00
paravirt_ops.rst