【OLK-5.10】kvm计算领域相关bugfix回合

backport kvm bugfix patches(mostly from mainline)

Alexandru Elisei (1):
  KVM: arm64: Refuse to run VCPU if PMU is not initialized

Marc Zyngier (2):
  KVM: arm64: Add kvm_vcpu_has_pmu() helper
  KVM: arm64: Restore PMU configuration on first run

Sean Christopherson (1):
  KVM: x86: Properly reset MMU context at vCPU RESET/INIT

Wanpeng Li (3):
  KVM: X86: Fix missing local pCPU when executing wbinvd on all dirty
    pCPUs
  KVM: LAPIC: Write 0 to TMICT should also cancel vmx-preemption timer
  KVM: LAPIC: Keep stored TMCCT register value 0 after KVM_SET_LAPIC

xulei (1):
  kvm: SMM: fix losing SMI problem

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patch1:kvm: SMM: fix losing SMI problem

fix losing SMI problem

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patch2:KVM: X86: Fix missing local pCPU when executing wbinvd on all dirty pCPUs

In order to deal with noncoherent DMA, we should execute wbinvd on
all dirty pCPUs when guest wbinvd exits to maintain data consistency.
smp_call_function_many() does not execute the provided function on the
local core, therefore replace it by on_each_cpu_mask().

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patch3:KVM: LAPIC: Write 0 t

According to the SDM 10.5.4.1:

A write of 0 to the initial-count register effectively stops the local
  APIC timer, in both one-shot and periodic mode.

However, the lapic timer oneshot/periodic mode which is emulated by vmx-preemption
timer doesn't stop by writing 0 to TMICT since vmx->hv_deadline_tsc is still
programmed and the guest will receive the spurious timer interrupt later. This
patch fixes it by also cancelling the vmx-preemption timer when writing 0 to
the initial-count register.o TMICT should also cancel vmx-preemption timer

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patch4:KVM: x86: Properly reset MMU context at vCPU RESET/INIT

Reset the MMU context at vCPU INIT (and RESET for good measure) if CR0.PG
was set prior to INIT.  Simply re-initializing the current MMU is not
sufficient as the current root HPA may not be usable in the new context.
E.g. if TDP is disabled and INIT arrives while the vCPU is in long mode,
KVM will fail to switch to the 32-bit pae_root and bomb on the next
VM-Enter due to running with a 64-bit CR3 in 32-bit mode.

This bug was papered over in both VMX and SVM, but still managed to rear
its head in the MMU role on VMX.  Because EFER.LMA=1 requires CR0.PG=1,
kvm_calc_shadow_mmu_root_page_role() checks for EFER.LMA without first
checking CR0.PG.  VMX's RESET/INIT flow writes CR0 before EFER, and so
an INIT with the vCPU in 64-bit mode will cause the hack-a-fix to
generate the wrong MMU role.

In VMX, the INIT issue is specific to running without unrestricted guest
since unrestricted guest is available if and only if EPT is enabled.
Commit 8668a3c468ed ("KVM: VMX: Reset mmu context when entering real
mode") resolved the issue by forcing a reset when entering emulated real
mode.

In SVM, commit ebae871a509d ("kvm: svm: reset mmu on VCPU reset") forced
a MMU reset on every INIT to workaround the flaw in common x86.  Note, at
the time the bug was fixed, the SVM problem was exacerbated by a complete
lack of a CR4 update.

The vendor resets will be reverted in future patches, primarily to aid
bisection in case there are non-INIT flows that rely on the existing VMX
logic.

Because CR0.PG is unconditionally cleared on INIT, and because CR0.WP and
all CR4/EFER paging bits are ignored if CR0.PG=0, simply checking that
CR0.PG was '1' prior to INIT/RESET is sufficient to detect a required MMU
context reset.

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patch5:KVM: LAPIC: Keep stored TMCCT register value 0 after KVM_SET_LAPIC

KVM_GET_LAPIC stores the current value of TMCCT and KVM_SET_LAPIC's memcpy
stores it in vcpu->arch.apic->regs, KVM_SET_LAPIC could store zero in
vcpu->arch.apic->regs after it uses it, and then the stored value would
always be zero. In addition, the TMCCT is always computed on-demand and
never directly readable.

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patch6-7:KVM: arm64: Refuse to run VCPU if PMU is not initialized

When enabling the PMU in kvm_arm_pmu_v3_enable(), KVM returns early if the
PMU flag created is false and skips any other checks. Because PMU emulation
is gated only on the VCPU feature being set, this makes it possible for
userspace to get away with setting the VCPU feature but not doing any
initialization for the PMU. Fix it by returning an error when trying to run
the VCPU if the PMU hasn't been initialized correctly.

The PMU is marked as created only if the interrupt ID has been set when
using an in-kernel irqchip. This means the same check in
kvm_arm_pmu_v3_enable() is redundant, remove it.

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patch8:KVM: arm64: Restore PMU configuration on first run

Restoring a guest with an active virtual PMU results in no perf
counters being instanciated on the host side. Not quite what
you'd expect from a restore.

In order to fix this, force a writeback of PMCR_EL0 on the first
run of a vcpu (using a new request so that it happens once the
vcpu has been loaded). This will in turn create all the host-side
counters that were missing.

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