Commit a4baf8d2 authored by Peter Collingbourne's avatar Peter Collingbourne Committed by Marc Zyngier
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Documentation: document the ABI changes for KVM_CAP_ARM_MTE 



Document both the restriction on VM_MTE_ALLOWED mappings and
the relaxation for shared mappings.

Signed-off-by: default avatarPeter Collingbourne <pcc@google.com>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Reviewed-by: default avatarCornelia Huck <cohuck@redhat.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221104011041.290951-9-pcc@google.com
parent c911f0d4

Documentation/virt/kvm/api.rst

+3 −2
Original line number Diff line number Diff line
@@ -7385,8 +7385,9 @@ hibernation of the host; however the VMM needs to manually save/restore the 
tags as appropriate if the VM is migrated.



When this capability is enabled all memory in memslots must be mapped as

not-shareable (no MAP_SHARED), attempts to create a memslot with a

MAP_SHARED mmap will result in an -EINVAL return.

``MAP_ANONYMOUS`` or with a RAM-based file mapping (``tmpfs``, ``memfd``),

attempts to create a memslot with an invalid mmap will result in an

-EINVAL return.



When enabled the VMM may make use of the ``KVM_ARM_MTE_COPY_TAGS`` ioctl to

perform a bulk copy of tags to/from the guest.