Re: 2.1.111: IDE DMA disabled...BLAH...BLAH...

Mike Jagdis (
Wed, 29 Jul 1998 17:16:04 +0100 (GMT/BST)

Incidentally, before 2.2 we should have some way of preventing the
mixing of UP and SMP kernel/modules. Currently loading an SMP
compiled module against a UP compiled kernel usually fails because
symbols involved in locking are missing. The killer is that UP
compiled modules usually load against an SMP compiled kernel
quite happily - but lack necessary locking or have wrong ideas
about structs (task_struct changes size with NR_CPUS...).

A UP iBCS will load against an SMP kernel but seg fault everything
because of the task_struct size change. A UP raid1 module will
load against an SMP kernel, even appear to work (although I'd
hate to stress it), but you can't mdstop the device once it is

No, this is not the source of my crashes - we use iBCS far too
heavily not to notice something wrong within seconds. I would
hate to think what it could do to others though :-).


|  Mike Jagdis                  |  Internet:   |
|  Roan Technology Ltd.         |                                      |
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