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bhyve: enlarge 64-bit PCI MMIO hole to 1 TiB
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Authored by tsoome on Wed, May 6, 10:23 AM.
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Details

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bhyve
Summary

Default 32 GiB hole is insufficient for modern GPUs whose BAR1 (HBM
aperture) is 128 GiB each. Four H100 SXM5 GPUs need ~512 GiB of
prefetchable 64-bit PCI MMIO. Bump to 1 TiB for headroom, covering
future hardware like H200 (192 GiB/GPU).

Assisted-By: Claude Opus 4.7 (1M context)

Diff Detail

Repository
rG FreeBSD src repository
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Lint Passed
Unit
No Test Coverage
Build Status
Buildable 72843
Build 69726: arc lint + arc unit

Event Timeline

Was this change motivated by this comment in PR290920 and have you tested this patch somehow yet?
If not, I think that commenter would be more than willing to test it.