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author | Oliver Upton <oliver.upton@linux.dev> | 2023-04-04 15:40:38 +0000 |
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committer | Marc Zyngier <maz@kernel.org> | 2023-04-05 12:07:41 +0100 |
commit | e65733b5c59a1ea20324a03494364958bef3fc68 (patch) | |
tree | 0cab1bf283e8914a637776b3427a0abfdf0a55f2 /Documentation/virt | |
parent | e8d018dd0257f744ca50a729e3d042cf2ec9da65 (diff) | |
download | lwn-e65733b5c59a1ea20324a03494364958bef3fc68.tar.gz lwn-e65733b5c59a1ea20324a03494364958bef3fc68.zip |
KVM: x86: Redefine 'longmode' as a flag for KVM_EXIT_HYPERCALL
The 'longmode' field is a bit annoying as it blows an entire __u32 to
represent a boolean value. Since other architectures are looking to add
support for KVM_EXIT_HYPERCALL, now is probably a good time to clean it
up.
Redefine the field (and the remaining padding) as a set of flags.
Preserve the existing ABI by using bit 0 to indicate if the guest was in
long mode and requiring that the remaining 31 bits must be zero.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230404154050.2270077-2-oliver.upton@linux.dev
Diffstat (limited to 'Documentation/virt')
-rw-r--r-- | Documentation/virt/kvm/api.rst | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 62de0768d6aa..9b01e3d0e757 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -6218,8 +6218,7 @@ to the byte array. __u64 nr; __u64 args[6]; __u64 ret; - __u32 longmode; - __u32 pad; + __u64 flags; } hypercall; Unused. This was once used for 'hypercall to userspace'. To implement |