d8ba8ba4c8
Closer inspection of the Xen code shows that we aren't supposed to be using the XEN_RUNSTATE_UPDATE flag unconditionally. It should be explicitly enabled by guests through the HYPERVISOR_vm_assist hypercall. If we randomly set the top bit of ->state_entry_time for a guest that hasn't asked for it and doesn't expect it, that could make the runtimes fail to add up and confuse the guest. Without the flag it's perfectly safe for a vCPU to read its own vcpu_runstate_info; just not for one vCPU to read *another's*. I briefly pondered adding a word for the whole set of VMASST_TYPE_* flags but the only one we care about for HVM guests is this, so it seemed a bit pointless. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20221127122210.248427-3-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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| .. | ||
| acrn | ||
| coco | ||
| hyperv | ||
| kvm | ||
| uml | ||
| guest-halt-polling.rst | ||
| index.rst | ||
| ne_overview.rst | ||
| paravirt_ops.rst | ||