Bug in the sg driver

[Dag Nygren <dag@newtech.fi>]

Hi,

just got back from a customer with major problems
with a LTO-drive and an Adaptec 19160.

The problems was ones that HP claimed a firmware
upgrade would fix and even gave a tool for doing this:
hp_ltt.

Running this the first time would always segfault and trying
a second time would consistently panic the system.

We traced the segfault to sg_ioctl trying to do something.
After finding a vague hint with google I tried to boot with
mem=512M (The machine has 2GB of memory) and voila:
The update worked without any crashes.
We don't know yet if the firmware update fixed the original problem,
but the conclusion is:

sg_ioctl seems to address illegal parts of memory when used with
kernels where highmem is enabled.

Any sg-driver maintainers out there?

Best Regards

-- 
Dag Nygren                               email: dag@newtech.fi
Oy Espoon NewTech Ab                     phone: +358 9 8024910
Träsktorpet 3                              fax: +358 9 8024916
02360 ESBO                              Mobile: +358 400 426312
FINLAND