Monitor kernel variable with ddb(4)

[Farhan Khan]

Hi all,

I am trying to figure out where a net80211's vap flags are modified. I see
that memory is originally allocated here:
http://src.illumos.org/source/xref/freebsd-head/sys/net/if.c#445. However,
I cannot figure out where the ifp->if_flags and if->if_drv_flags are ever
modified in the kernel.

Someone suggested using ddb(4), so I entered the live debugger using sysctl
debug.kdb.enter=1

I then set a breakpoint at if_alloc.

However, I cannot seem to figure out the next steps to monitor where the
ifp->if_flags or if->if_drv_flags are updated.

Full explanation - My kernel module is immediately unloading, but I am not
certain why. I traced it back in the ieee80211 code to those flags, but not
sure where they are updated.

Any ideas? Thank you!
--
Farhan Khan
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