linuxkpi: Move LINUXKPI_PROT_VALID higher
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Authored by andrew on Jul 1 2026, 10:10 AM.

Details

Reviewers

None

Group Reviewers

arm64
linuxkpi

Summary

Move LINUXKPI_PROT_VALID and LINUXKPI_CACHE_MODE_SHIFT out of the
bottom 8 bits. This allows the entire vm_prot_t to be stored in the
LinuxKPI pgprot_t.

This will be needed when we add more flags to vm_prot_t, e.g. for MTE
on arm64.

Diff Detail

Repository

rG FreeBSD src repository

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Build Status

Buildable 74453
Build 71336: arc lint + arc unit

Event Timeline

andrew created this revision.Jul 1 2026, 10:10 AM

Herald added subscribers: linuxkpi, emaste, imp. · View Herald TranscriptJul 1 2026, 10:10 AM

andrew requested review of this revision.Jul 1 2026, 10:10 AM

Harbormaster completed remote builds in B74453: Diff 181163.Jul 1 2026, 10:10 AM

andrew added a parent revision: D57990: amr64: Switch from PV_MTE_TAGGED to PV_MTE_CLEAN.Jul 1 2026, 10:10 AM

andrew added a child revision: D57992: arm64: Add mte_enabled to see if MTE is enabled.

andrew added a reviewer: linuxkpi.Jul 1 2026, 10:11 AM

emaste added a project: linuxkpi.Mon, Aug 17, 4:59 PM

Is anyone who knows about LinuxKPI able to check this? I don't have anything that uses it, but need to move the value for MTE.

This came from 1ea4c85781e94 and was revised in ebf854802d83a.

@ashafer has an open review ( https://reviews.freebsd.org/D59436 ) and I was trying to understand some of this recently.
If you can give me a few days I'll try to fully wrap my head around this.

I assume @ashafer and @dumbbell can test this for nvidia and i915/amdgpu.

This seems reasonable to me

Revision Contents
Changeset List

Path

Size

sys/

compat/

linuxkpi/

common/

include/

linux/

page.h

6 lines

Diff 181163

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sys/compat/linuxkpi/common/include/linux/page.h

linuxkpi: Move LINUXKPI_PROT_VALID higherNeeds ReviewPublicActions