[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Testing on PowerMac G4
From: |
Robert Millan |
Subject: |
Re: Testing on PowerMac G4 |
Date: |
Thu, 3 Jan 2008 13:11:12 +0100 |
User-agent: |
Mutt/1.5.13 (2006-08-11) |
On Thu, Jan 03, 2008 at 03:09:17AM -0500, Pavel Roskin wrote:
> Quoting Robert Millan <address@hidden>:
>
> >just take the grub-mkimage.c part of it and try to revert it on CVS HEAD,
> >that would confirm it's a grub-mkimage problem. Then apply the hunks
> >selectively untill you find the exact change that broke it. And finally
> >it's just a matter of "looking hard" at that hunk untill it's coerced to
> >reveal the problem :-)
>
> OK, here's what I have so far. The patch tries to make the memory
> layout more compact. Two changes are make to the layout. kernel.elf
> is loaded at 64k instead of 2M and the modules are loaded at the
> lowest 4k boundary after kernel.elf rather that at 3M.
>
> Moving the kernel.elf load address is fine. Moving the modules is not.
>
> The module base address is calculated separately in kernel.elf and in
> grub-mkimage. kernel.elf uses the "_end" symbol, whereas grub-mkimage
> looks for the ELF segment with the highest end address.
Ok, so you mean this setting:
phdr->p_vaddr = grub_host_to_target32 (modbase);
phdr->p_paddr = grub_host_to_target32 (modbase);
is not what it's used to calculate _end ?
I thought _end was calculated by the ELF loader (our own ELF loader,
multiboot.c seems to calculate _end and pass it to its payload).
> One problem in grub-mkimage is the infamous build ID, which is present
> in kernel.elf. It is located in a loadable segment starting at
> 0x10000d4 (i.e. just about 256M). That's what confuses objcopy, and
> it must be confusing grub-mkimage as well.
Isn't build ID a recent change in binutils? We had this problem for a while.
> I actually doubt that it's the right behavior to go through segments.
No idea about that I'm afraid :-(
> Linux style description. The first line is the synopsis. If it
> doesn't fit 72 characters, the patch is a candidate for splitting.
> Then an empty line. Then a more detailed description of the patch,
> including the motivation behind the changes. The list of the affected
> files can be generated by the version control system.
Looks good. But I guess you'll have to convince Marco and Okuji about this :-)
> The linear ChangeLog with everybody changing it in the same place (in
> the beginning) doesn't work well with parallel development.
It's not that much of a problem, I just write them in the patch header and
copy them at the last minute before commit.
> >>disk/ieee1275/ofdisk.c:65: Opening `ide1/disk:0'.
> >>disk/ieee1275/ofdisk.c:74: Opened `ide1/disk:0' as handle 0xff9d1c00.
> >>kern/disk.c:299: Opening `ide1/disk' failed.
> >>kern/disk.c:312: Closing `ide1/disk'.
> >
> >This seems to be contradictory. If OF returned a handle, why does the
> >open fail ? Looks like GRUB doesn't like something but isn't telling you
> >what. I'd investigate that part; at the least it can mean our error
> >handling isn't good enough.
>
> Actually, there are no "failures" with the version from 2007-02-20.
Does a snapshot from 2007-02-21 also have this problem?
> But maybe it's because in the normal mode with all modules loaded,
> unlike bare kernel.elf.
But you don't need modules for ofdisk to work, it's built into the kernel.
--
Robert Millan
<GPLv2> I know my rights; I want my phone call!
<DRM> What use is a phone call, if you are unable to speak?
(as seen on /.)
- Re: Testing on PowerMac G4, Pavel Roskin, 2008/01/02
- Re: Testing on PowerMac G4, Robert Millan, 2008/01/02
- Re: Testing on PowerMac G4, Pavel Roskin, 2008/01/03
- Re: Testing on PowerMac G4,
Robert Millan <=
- Re: Testing on PowerMac G4, Pavel Roskin, 2008/01/03
- Re: Testing on PowerMac G4, Robert Millan, 2008/01/03
- Re: Testing on PowerMac G4, Pavel Roskin, 2008/01/03
- Re: Testing on PowerMac G4, Robert Millan, 2008/01/04
- Re: Testing on PowerMac G4, Robert Millan, 2008/01/04
- Re: Testing on PowerMac G4, Pavel Roskin, 2008/01/04
- Re: Testing on PowerMac G4, Robert Millan, 2008/01/04
- Re: Testing on PowerMac G4, Yoshinori K. Okuji, 2008/01/04
- Re: Testing on PowerMac G4, Robert Millan, 2008/01/05
- Re: Testing on PowerMac G4, Pavel Roskin, 2008/01/04