# dtrace against kernel module prior to kldload



## Farhan Khan (Mar 15, 2017)

I am trying to run dtrace against the function rtwn_pci_write_1 )http://src.illumos.org/source/xref/freebsd-head/sys/dev/rtwn/pci/rtwn_pci_reg.c#55). It is located in if_rtwn_pci.

Prior to loading the module, there is no probe available for rtwn_pci_write_1, so I cannot use dtrace yet. However, when I load the module, it loads too quickly to capture run dtrace in time and capture probes.

I tried to use the -Z flag and then load the driver, but it seemed to fail to catch any probes.

Any ideas on how I should approach this issue? I'm a dtrace noob.


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## Pegasus711 (Apr 20, 2017)

Hi Farhan

This could be better answered via the mailing list (perhaps FreeBSD-current/FreeBSD-driver/FreeBSD-hackers).


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