ddi-forceattach(9P) Kernel Properties for Drivers ddi-forceattach(9P)NAME
ddi-forceattach, ddi-no-autodetach, ddi-no-modunload - properties con‐
trolling driver attach/detach and module unload behavior
DESCRIPTION
Solaris device drivers are attached by devfsadm(1M) and by the kernel
in response to open(2) requests from applications. Drivers not cur‐
rently in use can be detached when the system experiences memory pres‐
sure. 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 prop‐
erty is set to 1, the kernel will not auto-detach driver due to system
memory pressure.
Note that ddi-forceattach implies ddi-no-autodetach. Neither the ddi-
forceattach nor ddi-no-autodetach properties prevent driver detaching
in response to reconfiguration requests, such as executing commands
cfgadm(1M), modunload(1M), rem_drv(1M), and update_drv(1M).
The ddi-no-modunload is an integer property to be set globally by means
of the driver.conf(4) file. When this property is set to 1, the driver
module is locked in memory and cannot be unloaded by modunload,
rem_drv, or update_drv; the operation of cfgadm, however, remains unaf‐
fected.
Setting any of these properties to a non-integer value or an integer
value not equal to 1 produces undefined results
SEE ALSOcfgadm(1M), modunload(1M), rem_drv(1M), update_drv(1M), driver.conf(4)
Writing Device Drivers
WARNINGS
Clearing the ddi-no-modunload property in a vendor-delivered
driver.conf file could cause system instability.
The use of the ddi-no-modunload property is indicative that the deliv‐
ered driver is broken in some way and that a cleaner version of the
driver should be pursued. Thus, the use of this property is a temporary
workaround which should be removed when the driver is fixed.
SunOS 5.10 3 Apr 2012 ddi-forceattach(9P)
