mirror of https://gitee.com/openkylin/linux.git
d3457c877b
Hyper-V identifies vCPUs by Virtual Processor Index, which can be queried via HV_X64_MSR_VP_INDEX msr. It is defined by the spec as a sequential number which can't exceed the maximum number of vCPUs per VM. APIC ids can be sparse and thus aren't a valid replacement for VP indices. Current KVM uses its internal vcpu index as VP_INDEX. However, to make it predictable and persistent across VM migrations, the userspace has to control the value of VP_INDEX. This patch achieves that, by storing vp_index explicitly on vcpu, and allowing HV_X64_MSR_VP_INDEX to be set from the host side. For compatibility it's initialized to KVM vcpu index. Also a few variables are renamed to make clear distinction betweed this Hyper-V vp_index and KVM vcpu_id (== APIC id). Besides, a new capability, KVM_CAP_HYPERV_VP_INDEX, is added to allow the userspace to skip attempting msr writes where unsupported, to avoid spamming error logs. Signed-off-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> |
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| .. | ||
| arm | ||
| devices | ||
| 00-INDEX | ||
| api.txt | ||
| cpuid.txt | ||
| halt-polling.txt | ||
| hypercalls.txt | ||
| locking.txt | ||
| mmu.txt | ||
| msr.txt | ||
| nested-vmx.txt | ||
| ppc-pv.txt | ||
| review-checklist.txt | ||
| s390-diag.txt | ||
| timekeeping.txt | ||
| vcpu-requests.rst | ||