I think it was a mistake mentioning the additional patches and the oops. The
main problem for me at the moment is the SCSI CD-Rom errors. The oops and
subsequent errors are almost certainly because of that although I suppose if
everything was OK they wouldn't happen either.
Something is broken in the SCSI CD-ROM driver and I should have concentrated
on that.
The same sort of errors happen with a plain 2.0.29 kernel and SCSI CD-Rom
but copying with an IDE CD-Rom drive is perfectly OK.
Gerard Roudier wrote:
>
>
>
> The patch against pre-2.0.30-2 I've sent that tries to fix the memory
> problem, allows 1 recursion involving get_more_buffer_headers() in order
> not to use GFP_ATOMIC allocation. That is a bit dangerous for the kernel
> stacks and obviously I did'nt test it in all cases. The right approach is
> probably to use GFP_ATOMIC allocation for buffer headers at least for
> page IO but being given that:
> - min_free_pages = memory size / 128 = 0.78 % of the whole memory,
> - sizeof(buffer_head) is about 76 bytes for x86 -> 80/1024 = 7.8 % of the
> same memory,
> starting asynchronously page IOs for 10% of the whole memory can eat all
> the reserved pages for buffer headers. The fact that buffers can be
> allocated at ATOMIC priority also did'nt help.
> In my opinion, some changes are to be done in the kernel, in order not to
> do too much asynchronous IO for pages when free memory becomes too low.
> Such changes in the kernel are beyond my skills.
>
> Gerard.
I'm not really sure what all this means - I just happened to be using a
kernel with pre-patch-2.0.31-2 and your patch when I first noticed the
errors while copying CD's.
I had been checking some other operations and just decided to try a copy
to see what happened.
The messages are basically the same with 2.0.29 - and are from ../fs/isofs/inode.c
Structures used by inode.c seem to be set up incorrectly by the SCSI CD-Rom
driver and is why the errors appear NOT because the CD is defective - isofs is
lying - sorry, no it's not, it's being given incorrect information.
> >
> >
> > Warning: defective cdrom (volume sequence number). Enabling "cruft" mount option.
> > File unit size != 0 for ISO file (954846).
> > Interleaved files not (yet) supported.
> > File unit size != 0 for ISO file (934328).
> > File unit size != 0 for ISO file (934438).
> > File unit size != 0 for ISO file (1014204).
> > File unit size != 0 for ISO file (862672).
> > Interleaved files not (yet) supported.
> > File unit size != 0 for ISO file (870830).
> > File unit size != 0 for ISO file (860580).
> > File unit size != 0 for ISO file (813508).
> > kmalloc of too large a block (67702033 bytes).
> > Interleaved files not (yet) supported.
> >
> >
-- Richard Waltham | Work: richard@digtalinterface.demon.co.uk At home in | Home: dormouse@farsrobt.demon.co.uk Southampton UK | Compuserve 100421.1276