USB2: booting from usb memory issue, including a foolish patch

[Robert Watson]

On Thu, 19 Feb 2009, Hans Petter Selasky wrote:

>> I have checked a patch on above URL (freesbie term), it looks like better 
>> than mine. How about to merge that patch to usb2 stack, HPS?
>>
>> If someone could add feature that waits all boot deives prove, that's best. 
>> And adding tuning feature of 16 seconds wait time by /boot/loader.conf, 
>> it's great. Anyone could do that?
>
> Could we change "mount", that if we specify some wait flag, it will simply 
> loop in kernel and userland for a user specified amount of time?

I thought run_interrupt_driven_config_hooks(), done at 
SI_SUB_INT_CONFIG_HOOKS, allowed subsystems such as SCSI to suspend the boot 
while they finish probing, and root_mount_hold() similarly allowed higher 
level subsystems such as GEOM modules to delay the root mount while they do 
their bit.

Robert N M Watson
Computer Laboratory
University of Cambridge