[PATCH 0/2] x86/hyper-v: cope with VP_INVAL in PV TLB flush code

[Vitaly Kuznetsov <vkuznets@redhat.com>]

Commit 1268ed0c474a ("x86/hyper-v: Fix the circular dependency in IPI
 enlightenment") made it possible to observe VP_INVAL returned from 
hv_cpu_number_to_vp_number() and cpumask_to_vpset() and PV TLB flush
code needs to be adjusted.

The window when VP_INVAL is observable is very short, I'm not even sure
we do TLB flushes during this period (secodary CPUs bringup on boot, there
is no CPU hotplug on Hyper-V yet). This, however, may change in future so
let's fix this now.

Thomas, Ingo: these patches are for 'tip/x86/hyperv'. I don't think we have
a real issue in 4.18 but I can definitely prepare fixes for it if you think
this is needed.

Vitaly Kuznetsov (2):
  x86/hyper-v: check cpumask_to_vpset() return value in
    hyperv_flush_tlb_others_ex()
  x86/hyper-v: check for VP_INVAL in hyperv_flush_tlb_others()

 arch/x86/hyperv/mmu.c | 7 +++++++
 1 file changed, 7 insertions(+)

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2.14.4