31 lines
1.0 KiB
Plaintext
31 lines
1.0 KiB
Plaintext
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POWER (PAPR) Protected Execution Facility (PEF)
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===============================================
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Protected Execution Facility (PEF), also known as Secure Guest support
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is a feature found on IBM POWER9 and POWER10 processors.
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If a suitable firmware including an Ultravisor is installed, it adds
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an extra memory protection mode to the CPU. The ultravisor manages a
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pool of secure memory which cannot be accessed by the hypervisor.
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When this feature is enabled in QEMU, a guest can use ultracalls to
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enter "secure mode". This transfers most of its memory to secure
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memory, where it cannot be eavesdropped by a compromised hypervisor.
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Launching
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---------
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To launch a guest which will be permitted to enter PEF secure mode:
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# ${QEMU} \
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-object pef-guest,id=pef0 \
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-machine confidential-guest-support=pef0 \
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...
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Live Migration
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----------------
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Live migration is not yet implemented for PEF guests. For
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consistency, we currently prevent migration if the PEF feature is
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enabled, whether or not the guest has actually entered secure mode.
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