Page MenuHomeFreeBSD
Differential D51173

amd64: fix physmap entry addition logic
ClosedPublic
Actions

Authored by vexeduxr on Jul 5 2025, 8:43 PM.
Tags
None
Referenced Files
Unknown Object (File)
Mon, Oct 13, 11:37 AM
Unknown Object (File)
Mon, Oct 13, 11:36 AM
Unknown Object (File)
Mon, Oct 13, 11:36 AM
Unknown Object (File)
Mon, Oct 13, 11:36 AM
Unknown Object (File)
Sun, Oct 12, 10:56 PM
Unknown Object (File)
Sep 10 2025, 7:56 AM
Unknown Object (File)
Sep 9 2025, 7:23 AM
Unknown Object (File)
Sep 8 2025, 9:19 PM
View All 28 Files
Subscribers
imp

Details

Reviewers
kib
markj
jhb
Commits
rGefe5907279e1: amd64: fix physmap entry addition logic
Summary

Since physmap_idx points to the next slot, we should make sure both 'i'
and 'insert_idx' are less than physmap_idx, but never equal to it.

Also allow physmap_idx to reach PHYS_AVAIL_ENTRIES so the last slot can
be populated.

Diff Detail

Repository
rG FreeBSD src repository
Lint
Lint Skipped
Unit
Tests Skipped
Build Status
Buildable 65236
Build 62119: arc lint + arc unit

Event Timeline

vexeduxr created this revision.Jul 5 2025, 8:43 PM
Herald added a subscriber: imp. · View Herald TranscriptJul 5 2025, 8:43 PM
vexeduxr requested review of this revision.Jul 5 2025, 8:43 PM
Harbormaster completed remote builds in B65233: Diff 158031.Jul 5 2025, 8:43 PM
kib accepted this revision.Jul 6 2025, 1:23 PM
kib added inline comments.
sys/amd64/amd64/machdep.c
679

Then would it make sense to move this operation down even more, after the 'move' loop, so that i initialization does not need to '-2'?

This revision is now accepted and ready to land.Jul 6 2025, 1:23 PM
vexeduxr added inline comments.Jul 6 2025, 5:30 PM
sys/amd64/amd64/machdep.c
679

Ah, yes it would.

vexeduxr updated this revision to Diff 158054.Jul 6 2025, 5:32 PM

Move physmap_idx addition further down

This revision now requires review to proceed.Jul 6 2025, 5:32 PM
Harbormaster completed remote builds in B65236: Diff 158054.Jul 6 2025, 5:32 PM
markj accepted this revision.Jul 6 2025, 5:49 PM
This revision is now accepted and ready to land.Jul 6 2025, 5:49 PM
kib added inline comments.Jul 6 2025, 5:51 PM
sys/amd64/amd64/machdep.c
673

This statement also needs an adjustment, otherwise when we hit the limit by adding the entry, we still move entries. It should be physmap_idx == PHYL_AVAIL_ENTRIES - 2 (right hand is const).

vexeduxr added inline comments.Jul 6 2025, 6:00 PM
sys/amd64/amd64/machdep.c
673

I don't think I follow. if physmap_idx is PHYL_AVAIL_ENTRIES - 2, then we still have a free pair.

kib accepted this revision.Jul 6 2025, 6:10 PM
kib added inline comments.
sys/amd64/amd64/machdep.c
673

Right, sorry.

Closed by commit rGefe5907279e1: amd64: fix physmap entry addition logic (authored by vexeduxr). · Explain WhyJul 6 2025, 7:28 PM
This revision was automatically updated to reflect the committed changes.
vexeduxr added a commit: rGefe5907279e1: amd64: fix physmap entry addition logic.

Revision Contents
Changeset List

PathSize
sys/
amd64/
amd64/
11 lines

Diff 158054

View Options

sys/amd64/amd64/machdep.c

Loading...