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vmm: increase vlapic version

Description

vmm: increase vlapic version

Mac os panics on apic versions lower than 0x14.

See https://opensource.apple.com/source/xnu/xnu-7195.81.3/osfmk/i386/lapic_native.c.auto.html

Additionally, an upcoming commit will validate the icr values written by
the guest. Older intel processors allow some different combinations than
the newer ones. AMD documents that only the newer combinations are
allowed. So, bumping the version allows us to avoid a differentiation
between AMD and Intel.

Intel documents that newer processors than the P6 are using the new
combinations. Sadly, Intel does not document which apic version belongs
to those processors. Linux identifies newer apics by a version larger or
equal to 0x14. Intel and AMD allow apic version between 0x10 and 0x15.
So, using 0x14 seems to be fine.

See https://github.com/torvalds/linux/blob/3eba620e7bd772a0c7dc91966cb107872b54a910/arch/x86/kernel/apic/apic.c#L238

Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D36945
Sponsored by: Beckhoff Automation GmbH & Co. KG

Details

Provenance
corvinkAuthored on Oct 10 2022, 12:56 PM
manuCommitted on Oct 14 2022, 10:03 AM
Reviewer
jhb
Differential Revision
D36945: vmm: increase vlapic version
Parents
rG0bda8d3e9f7a: vmm: permit some IPIs to be handled by userspace
Branches
Unknown
Tags
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