Release kernels have no KDB backends enabled, so they discard an NMI if it is not due to a hardware failure. This includes NMIs from IPMI BMCs and hypervisors. Furthermore, the interaction of panic_on_nmi, kdb_on_nmi, and debugger_on_panic is confusing. Respond to all NMIs according to panic_on_nmi and debugger_on_panic. Remove kdb_on_nmi. Expand the meaning of panic_on_nmi by making it a bitfield. There are currently two bits: one for NMIs due to hardware failure, and one for all others. Leave room for more. If panic_on_nmi and debugger_on_panic are both true, don't actually panic, but directly enter the debugger, to allow someone to leave the debugger and [hopefully] resume normal execution. Reviewed by: kib MFC after: 2 weeks Relnotes: yes: machdep.kdb_on_nmi is gone; machdep.panic_on_nmi changed Sponsored by: Dell EMC Isilon Differential Revision: https://reviews.freebsd.org/D24558 |
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acpica | ||
bios | ||
conf | ||
cpufreq | ||
include | ||
iommu | ||
isa | ||
pci | ||
x86 | ||
xen |