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OcAppleKernelLib: Fix zero divisor in AMP topology initialization - #661
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The AMP path in ProvideCurrentCpuInfo hardcodes the package core ID capacity to 128. When XNU sees a smaller logical APIC ID capacity, dividing it by 128 gives zero. XNU then uses that result as a divisor during topology initialization. Use the logical APIC ID capacity exposed to XNU for the package patch so the flattened topology has one thread per core.
lzhoang2801
marked this pull request as draft
November 10, 2026 15:39
lzhoang2801
marked this pull request as ready for review
November 10, 2026 16:03
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The AMP patch in
ProvideCurrentCpuInfosetscpuid_cores_per_packageto 128. If the logical APIC ID capacity is smaller than 128, XNU gets zero threads per core and divides by zero during boot. Use the logical APIC ID capacity that XNU sees as the replacement value.Tested on multiple CPUs.
Fixes: dortania/bugtracker#336