[lkml]   [2006]   [Aug]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [Fastboot] [CFT] ELF Relocatable x86 and x86_64 bzImages
On Sat, Aug 12, 2006 at 01:20:29AM -0600, Eric W. Biederman wrote:
> Don Zickus <> writes:
> >> >>
> >> >> I'm a little disappointed but at this point it isn't a great surprise,
> >> >> the code is early yet and hasn't had much testing or attention.
> >> >> I wonder if I have missed something else silly.
> >> >>
> >> >> As for testing, can you use plain kexec to load the kernel at a
> >> >> different address? I'm curious to know if it is something related
> >> >> to the kexec on panic path or if it is just running at a different
> >> >> location that is the problem.
> >> >
> >
> > I think I have found the 'something silly'. Here is a patch that allows
> > our Dell em64t boxes to boot. This change matches the original code. The
> > main difference that caused the problems was the setting of _PAGE_NX bit.
> > This caused issues in early_io_remap().
> >
> > Thanks to Larry Woodman for debugging this.
> This looks like a different one but looks fairly sane.
> Do you know what code had problems having _PAGE_NX set.
> What are we doing with early_ioremap the requires execute
> permissions. It doesn't sound right that we would need
> this.

This fix is only needed for a subset of our em64t boxes, so it could be
just a chipset problem. Supposedly, if I remember the conversation
correctly, when the kernel first boots it reserves about 40MB and about 20
pmds automatically. After decompression, early_io_remap tries to setup
all the memory. The conflict arose when early_io_remap tried to reuse one
of those pmds. This caused the system to crash and reboot.

I'll try to get more info Monday on the specifics.


> Eric
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2006-08-12 17:27    [W:0.133 / U:22.704 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site