Commit d9459922 authored by Claudio Imbrenda's avatar Claudio Imbrenda Committed by Janosch Frank
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KVM: s390: pv: api documentation for asynchronous destroy 



Add documentation for the new commands added to the KVM_S390_PV_COMMAND
ioctl.

Signed-off-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: default avatarNico Boehr <nrb@linux.ibm.com>
Reviewed-by: default avatarSteffen Eiden <seiden@linux.ibm.com>
Reviewed-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20221111170632.77622-3-imbrenda@linux.ibm.com


Message-Id: <20221111170632.77622-3-imbrenda@linux.ibm.com>
Signed-off-by: default avatarJanosch Frank <frankja@linux.ibm.com>
parent fb491d55

Documentation/virt/kvm/api.rst

+37 −4
Original line number Diff line number Diff line
@@ -5163,10 +5163,13 @@ KVM_PV_ENABLE 
  =====      =============================



KVM_PV_DISABLE

  Deregister the VM from the Ultravisor and reclaim the memory that

  had been donated to the Ultravisor, making it usable by the kernel

  again.  All registered VCPUs are converted back to non-protected

  ones.

  Deregister the VM from the Ultravisor and reclaim the memory that had

  been donated to the Ultravisor, making it usable by the kernel again.

  All registered VCPUs are converted back to non-protected ones. If a

  previous protected VM had been prepared for asynchonous teardown with

  KVM_PV_ASYNC_CLEANUP_PREPARE and not subsequently torn down with

  KVM_PV_ASYNC_CLEANUP_PERFORM, it will be torn down in this call

  together with the current protected VM.



KVM_PV_VM_SET_SEC_PARMS

  Pass the image header from VM memory to the Ultravisor in
@@ -5289,6 +5292,36 @@ KVM_PV_DUMP 
    authentication tag all of which are needed to decrypt the dump at a

    later time.



KVM_PV_ASYNC_CLEANUP_PREPARE

  :Capability: KVM_CAP_S390_PROTECTED_ASYNC_DISABLE



  Prepare the current protected VM for asynchronous teardown. Most

  resources used by the current protected VM will be set aside for a

  subsequent asynchronous teardown. The current protected VM will then

  resume execution immediately as non-protected. There can be at most

  one protected VM prepared for asynchronous teardown at any time. If

  a protected VM had already been prepared for teardown without

  subsequently calling KVM_PV_ASYNC_CLEANUP_PERFORM, this call will

  fail. In that case, the userspace process should issue a normal

  KVM_PV_DISABLE. The resources set aside with this call will need to

  be cleaned up with a subsequent call to KVM_PV_ASYNC_CLEANUP_PERFORM

  or KVM_PV_DISABLE, otherwise they will be cleaned up when KVM

  terminates. KVM_PV_ASYNC_CLEANUP_PREPARE can be called again as soon

  as cleanup starts, i.e. before KVM_PV_ASYNC_CLEANUP_PERFORM finishes.



KVM_PV_ASYNC_CLEANUP_PERFORM

  :Capability: KVM_CAP_S390_PROTECTED_ASYNC_DISABLE



  Tear down the protected VM previously prepared for teardown with

  KVM_PV_ASYNC_CLEANUP_PREPARE. The resources that had been set aside

  will be freed during the execution of this command. This PV command

  should ideally be issued by userspace from a separate thread. If a

  fatal signal is received (or the process terminates naturally), the

  command will terminate immediately without completing, and the normal

  KVM shutdown procedure will take care of cleaning up all remaining

  protected VMs, including the ones whose teardown was interrupted by

  process termination.



4.126 KVM_XEN_HVM_SET_ATTR

--------------------------