Re: modularized kernels

On Sat, 14 Jul 2007 20:34:24 +0200 Rainer Weikusat <rweikusat@xxxxxxxxxxx> wrote:

| Ehh ... I don't usually compile modules I don't plan to use. But if
| everything is built-in, the only way to "fix" a subsystem in a serious
| state of confusion is a reboot. The USB host controller halt I was
| writing about used to happen a couple of times each day (on most
| days). A quick rmmod -f/ modprobe was faster than rebooting the box
| would have been.

Linux, being a monolithic kernel, if any "subsystem" is in a serious state
of confusion, the only action I would trust is a reboot.

BTW, I have encountered a USB controller problem a couple times on my Linux
desktop at work. It happened to have a stock kernel from FC6, so it had
modules I could have reloaded. However, I chose to do a reboot instead.
Guess what ... the problem remained. The controller was still in a state
of total confusion. So I shutdown again and this time pressed the reset
button while sitting at the next GRUB menu. Even that did not clear the
problem. It took a full power off then on cycle to clear it up.

BTW, what caused that problem was the insertion of a 2nd USB device during
I/O activity of the 1st USB device. This could possibly have resulted in
the 1st device connection being bumped loose enough to disrupt an ongoing
transfer. But USB is supposed to detect that and retry (I don't know if
the retry is supposed to be done by hardware or software, but the hardware
is certainly not supposed to freeze harder than a reset when it happens).

Hardware problems that force me to do a reboot are otherwise quite rare.
They happen even less at home than at work. Maybe that is because all my
home computers are hand built by myself.

And, I would not expect the average user to understand when reinserting a
driver would actually help. Such practices, IMHO, should be limited to
those who know what it does, and means, and when it is usable. And yet I
don't even care to myself.

| Phil Howard KA9WGN ( / Do not send to the address below |
| first name lower case at / spamtrap-2007-07-15-0849@xxxxxxxx |