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pci: Only re-route IRQs based on firmware on x86
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Authored by cperciva on Mar 28 2025, 6:12 PM.
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Details

Summary

There is a (very historical) call to pci_assign_interrupt for the
purpose of routing IRQs which may have been set up wrong by x86 BIOS
or firmware. On non-x86 systems, this is unnecessary; and on INTRNG
systems it results in a (synthetic) IRQ leak and ultimately a kernel
panic after many hotplug/unplug cycles.

Suggested by: jhb
MFC after: 2 weeks
Sponsored by: Amazon

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rG FreeBSD src repository
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Build 60070: arc lint + arc unit

Event Timeline

cperciva created this revision.
This revision is now accepted and ready to land.Mar 28 2025, 6:43 PM

Could it bring a new flow of messages into the kernel message buffer? After today's upgrade of my desktop PC, I see plenty of "Can't enable IRQ/MSI because no handler is installed," which didn't appear in the past.

It was triggered by D49543 (likely) and seems to be harmless so far.