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Manual Pages  — DEVMATCH


devmatch – print information about unattached devices



devmatch [-adhpuv] [--all] [--dump] [--hints file] [--nomatch event] [--unbound] [--verbose]


The devmatch utility, without any arguments, prints all the kernel modules it has found for all the unattached, enabled devices in the system.
-a --all
  Include all devices, not just the ones that are unattached.
-d --dump
  Produce a human readable dump of the linker.hints file.
-h --hints file
  Use the named file instead of linker.hints guessed from the current module load path.
-p --nomatch event
  Parse and use a standard NOMATCH event from devd(8) for matching instead of searching the device tree.
-u --unbound
  Attempt to produce a list of those drivers with PNP info whose driver tables with that PNP info can not be found.
-v --verbose
  Produce more verbose output.


devinfo(8), MODULE_PNP_INFO(9)


devmatch first appeared in FreeBSD 12.0 .


Warner Losh <Mt imp@FreeBSD.org>


The kernel has hints in it, but we exclude it from the list of modules to suggest for unmatched devices. We exclude it when suggesting drivers, but include it when looking for unbound devices or producing a full dump of linker.hints. This can be confusing.

Some modules are hard links in /boot/kernel and will be reported twice.

The PNP string's attributes are evaluated once per PNP entry on that bus rather than once.

The term PNP is overloaded in FreeBSD. It means, generically, the identifying data the bus provides about a device. While this include old ISA PNP identifiers, it also includes the logical equivalent in USB, PCI, and others.

Many drivers currently lack proper PNP table decorations and need to be updated.

DEVMATCH (8) October 12, 2020

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