DDI-FORCEATTACH(9P) Kernel Properties for Drivers DDI-FORCEATTACH(9P)


ddi-forceattach, ddi-no-autodetach - properties controlling driver
attach/detach behavior


Solaris device drivers are attached by devfsadm(1M) and by the kernel in
response to open(2) requests from applications. Drivers not currently in
use can be detached when the system experiences memory pressure. The ddi-
forceattach and ddi-no-autodetach properties can be used to customize
driver attach/detach behavior.

The ddi-forceattach is an integer property, to be set globally by means
of the driver.conf(4) file. Drivers with this property set to 1 are
loaded and attached to all possible instances during system startup. The
driver will not be auto-detached due to system memory pressure.

The ddi-no-autodetach is an integer property to be set globally by means
of the driver.conf(4) file or created dynamically by the driver on a per-
instance basis with ddi_prop_update_int(9F). When this property is set
to 1, the kernel will not auto-detach driver due to system memory

Note that ddi-forceattach implies ddi-no-autodetach. Setting either
property to a non-integer value or an integer value not equal to 1
produces undefined results. These properties do not prevent driver
detaching in response to reconfiguration requests, such as executing
commands cfgadm(1M), modunload(1M), rem_drv(1M), and update_drv(1M).



Writing Device Drivers

May 18, 2001 DDI-FORCEATTACH(9P)