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Hide SME from the guest so M4 apps stop dying with SIGILL - #374
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The M4 has SME but no SVE, and QEMU under HVF cannot drop SME from the vCPU. Code that runs an SVE instruction before smstart, such as Slack's camera path, then crashes with SIGILL. Add arm64.nosme through a new limine-entry-tool drop-in, listed as a backup file, and bump pkgrel. Earlier Apple chips have no SME, so nothing changes for them. Fixes omacom#372
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What changed and why
Fixes #372. On an M4 the guest reports
sme/sme2but nosve, and QEMU under HVF has nosmeproperty to turn it off. Code that runs an SVE instruction beforesmstart(Slack's camera path; likely libyuv, so other Chromium/Electron apps too) dies with SIGILL.This adds
/etc/limine-entry-tool.d/50-try-omarchy-cpu.confwithKERNEL_CMDLINE[default]+=" arm64.nosme", the fix the reporter tested. It is a separate drop-in from the console one so it can be dropped on its own once QEMU can hide SME under HVF. It is a pacmanbackupfile like the console drop-in, the package README lists it, andpkgrelis bumped. Chips before the M4 have no SME, so the option is a no-op there.Like the console drop-in, it takes effect when Limine's entries are next rebuilt: in the factory build, and on existing VMs at the next kernel update (or
sudo limine-update).Note: #373 also bumps
pkgrelto 24; whichever merges second needs 25, and I'll rebase.Testing
make test-guest: OK (new test checks the drop-in's command line and itsbackupentry)python3 tests/test-build-cache.py: OKmakepkg --printsrcinfolists the new backup filemake test,make e2e, a factory build, or booting on an M4 â I'm on Linux without an Apple Silicon Mac. The reporter's Slack crashes with SIGILL on camera use because the M4 guest reports SME without SVEÂ #372 test (same option via a drop-in) is the runtime evidence.