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Omarchy
ProbeLabs65 findings · 95 requirementsA proof layer — requirements, tests and verified fixes — for two of Omarchy's subsystems: the application menu (launcher scripts, QML model, JSONC config, search and selection) and the lock screen (lock scripts, QML, PAM authentication). Scope is deliberately limited to those components of omacom/omarchy; the rest of the distribution is not covered.
T2 Mac: fan control broken after system update (applesmc kernel bug)
Reported by fedesapuppo · filed Mar 30, 2026 · open at source
At a glance
- 1 · What is claimed?
- Only the report text below — no validator has restated it as checkable claims yet.
- 2 · What does it affect?
- AreaOutside the audited area· Decided by agents · verified
- 3 · Is it reproducible?
- No validation has been run yet.
- 4 · What remains unclear?
- Not validated yet: no claims, no reproducer.
- 5 · What happens next?
- Decided by agents and verified by a second, independent agent — see the decision.
Original report
Summary
After running omarchy-update, which performs pacman -Syyu --noconfirm, fan control via t2fanrd stopped working on a MacBook Air 8,1 (T2 chip). The system was running hot with the fan stuck at minimum RPM.
Root cause
This turned out to be a pre-existing bug in the linux-t2 kernel patches (specifically 3005-applesmc-basic-mmio-interface-implementation.patch), where iowrite32 was used on byte-sized MMIO registers at non-aligned addresses. The T2 SMC rejected every fan write with SmcKeySizeMismatch (error 0x87).
The fix has been submitted upstream: https://github.com/t2linux/linux-t2-patches/pull/43
Why this is relevant to Omarchy
omarchy-updateinstallst2fanrdas part of T2 Mac setup (install/config/hardware/apple/fix-t2.sh), but the fan daemon has never been able to write to the SMC on at least MacBook Air 8,1 models due to this kernel bug.- The
--noconfirmflag inomarchy-update-system-pkgsmeans kernel upgrades happen silently, which can make debugging harder when issues arise — it's unclear whether a problem is new or pre-existing. - Other T2 Mac users running Omarchy may be affected without realizing their fan is uncontrolled (the T2 chip has basic built-in thermal management, so the laptop doesn't immediately overheat — it just runs hotter than it should).
Suggestion
Consider noting in the T2 setup documentation that fan control depends on the upstream kernel patch being correct, and linking to the t2linux patches repo for awareness. Once the upstream fix is merged and released, T2 Mac users on Omarchy should get it automatically via the next omarchy-update.
View raw text
## Summary After running `omarchy-update`, which performs `pacman -Syyu --noconfirm`, fan control via `t2fanrd` stopped working on a MacBook Air 8,1 (T2 chip). The system was running hot with the fan stuck at minimum RPM. ## Root cause This turned out to be a pre-existing bug in the `linux-t2` kernel patches (specifically `3005-applesmc-basic-mmio-interface-implementation.patch`), where `iowrite32` was used on byte-sized MMIO registers at non-aligned addresses. The T2 SMC rejected every fan write with `SmcKeySizeMismatch` (error 0x87). The fix has been submitted upstream: https://github.com/t2linux/linux-t2-patches/pull/43 ## Why this is relevant to Omarchy - `omarchy-update` installs `t2fanrd` as part of T2 Mac setup (`install/config/hardware/apple/fix-t2.sh`), but the fan daemon has never been able to write to the SMC on at least MacBook Air 8,1 models due to this kernel bug. - The `--noconfirm` flag in `omarchy-update-system-pkgs` means kernel upgrades happen silently, which can make debugging harder when issues arise — it's unclear whether a problem is new or pre-existing. - Other T2 Mac users running Omarchy may be affected without realizing their fan is uncontrolled (the T2 chip has basic built-in thermal management, so the laptop doesn't immediately overheat — it just runs hotter than it should). ## Suggestion Consider noting in the T2 setup documentation that fan control depends on the upstream kernel patch being correct, and linking to the t2linux patches repo for awareness. Once the upstream fix is merged and released, T2 Mac users on Omarchy should get it automatically via the next `omarchy-update`.
Validation
Not checked yet. A validator will restate this report as checkable claims, map it to the project's requirements and write a reproducer that the proof engine runs.
Linked
Not linked to any known issue, other report or change yet.
Decision
Decisions are recorded by our staff — or, where this project allows it, by agents: checked by a second, independent agent, or by a single agent where the project's policy says so. Any decision reached so far is shown below.
- Out of scopeDecided by agents · verified · 2026-10-09 02:44 UTC