[Info-vax] Reloading device drivers on x86-64 VMS

[Stephen Hoffman]

On 2015-03-07 13:19:56 +0000, Simon Clubley said:

> I don't know if you can unload and reload device drivers on IA-64

Unloading drivers?  AFAIK, nope.  As for reloading, that can 
sorta-kinda usually work, if you're careful.

> (I've stopped at Alpha so far) or if the ability was added to Alpha in 
> the last few years (I haven't done any VMS kernel mode work for many 
> years) but if you can't, would it be possible to have device
> drivers for x86-64 VMS which can be unloaded and then a new version reloaded ?

Present VMS doesn't have a generic means to determine if a device is 
truly idle and can be unloaded, or that the data structures are all 
upward-compatible and such, thus... reboot.

> One thing which became very clear very quickly to me was just how much 
> easier it is to develop device drivers on Linux where you can do 
> exactly this.

Yep.

> I know it's not exactly a major feature for the majority of users but 
> if it's easy enough to add support for this it would be worthwhile as 
> it also has production implications in being able to load some updated 
> drivers without rebooting.

Though far from addressing your request, the remote system code 
debugger makes this work a little easier, as you're not resetting your 
development context nearly as often, though you're still waiting for 
the minimally-configured target box to reboot for some changes and for 
some errors.


-- 
Pure Personal Opinion | HoffmanLabs LLC