Re: 2.4.25-rc1: BUG: wrong zone alignment, it will crash

[Michael Frank <mhf@linuxmail.org>]

On Friday 06 February 2004 23:36, Rik van Riel wrote:
> On Fri, 6 Feb 2004, Michael Frank wrote:
> 
> > > > 300MB HIGHMEM available.
> > > > 195MB LOWMEM available.
> > > > On node 0 totalpages: 126960
> > > > zone(0): 4096 pages.
> > > > zone(1): 46064 pages.
> > > > zone(2): 76800 pages.
> > > > BUG: wrong zone alignment, it will crash
> 
> > It is supposed to work, just a bug in the zone alignment code.
> 
> The error isn't in the kernel, it's between the chair and the keyboard.
> You have created a lowmem zone of a size that doesn't correctly
> align with the largest blocks used by the buddy allocator.
> 
> > I have have to use HIGHMEM emulation for testing.
> 
> Then you'll need to choose a different size for the highmem=
> parameter, one that doesn't cause an unaligned boundary.

Which is not user friendly and does not match the documentation.

> 
> Alternatively, you could submit a patch so the highmem= boot
> option parsing code does the aligning for you.

OK, will do. I'll produce and test a patch.

> 
> However, that would simply be an improvement to the kernel and
> nothing like a bug you can demand to get fixed now.

OK, Please note that I only passed on the message produced by the kernel 
  BUG: wrong zone alignment, it will crash 

Perhaps the kernel should have reported it as "Invalid value for highmem" 
instead of "BUG" ;)

Thank you

Michael