Re: [Fastboot] [RFC] [PATCH 2/2] kdump: cciss driver initialization issue fix

[Andrew Morton <akpm@osdl.org>]

On Mon, 26 Jun 2006 13:04:40 -0400
Vivek Goyal <vgoyal@in.ibm.com> wrote:

> > Thanks Eric, that helps me understand. Section 8.2.2 of the open cciss
> > spec supports a reset message. Target 0x00 is the controller. We could
> > add this to the init routine to ensure the board is made sane again but
> > this would drastically increase init time under normal circumstances.
> > And I suspect this is a hard reset, also. Not sure if that would
> > negatively impact kdump. If there were some condition we could test
> > against and perform the reset when that condition is met it would not
> > impact 99.9% of users.
> 
> That's the precise reason of introducing the "crashboot" command line
> parameter. Driver authors can check against this condition and reset
> the device and 99.9% of the users are not impacted.

Yes, that is a legitimate use.

As long as there is indeed a noticeable downside to issuing the reset - if
it turns out that it just takes a few milliseconds then we'd be better off
dong the reset unconditionally.