kvm/x86/errata.rst

1 .. SPDX-License-Identifier: GPL-2.0
18 ----------------------------------
27 Clearing these bits in CPUID has no effect on the operation of the guest;
31 **Workaround:** It is recommended to always set these bits in guest CPUID.
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42 ------
45 vCPU has legacy xAPIC enabled, e.g. to bring up hotplugged vCPUs via INIT-SIPI
46 on VMs with > 255 vCPUs.  A side effect of the quirk is that, if multiple vCPUs
53 -----
54 KVM does not virtualize guest MTRR memory types.  KVM emulates accesses to MTRR
55 MSRs, i.e. {RD,WR}MSR in the guest will behave as expected, but KVM does not
56 honor guest MTRRs when determining the effective memory type, and instead
57 treats all of guest memory as having Writeback (WB) MTRRs.
60 ------
63 expected, but setting CR0.CD=1 has no impact on the cachaeability of guest
68 running in the guest.