From: "Vladimir 'φ-coder/phcoder' Serbinenko" <phcoder@gmail.com>
To: The development of GNU GRUB <grub-devel@gnu.org>
Subject: Re: [PATCH] powerpc: fix startup bss cleaning
Date: Tue, 16 Jul 2013 07:47:35 +0200 [thread overview]
Message-ID: <51E4DE77.40402@gmail.com> (raw)
In-Reply-To: <20130715151237.Horde.RWhdgZir309R5EmlUhPR2GA@imap.linux.ibm.com>
On 15.07.2013 21:12, Paulo Flabiano Smorigo/Brazil/IBM wrote:
> Hi,
>
> The trunk version of GRUB is crashing on power machines. Openfirmware
> returns the following message:
> Welcome to GRUB!
>
> DEFAULT CATCH!, exception-handler=fff00700
> at %SRR0: 0000000000003940 %SRR1: 0000000000083002
> Open Firmware exception handler entered from non-OF code
>
> Client's Fix Pt Regs:
> 00 000000000020a074 0000000001a3ff40 0000000000000000 00000000001e3de0
> 04 00000000001e3eb0 0000000000000004 00000000001d1fd0 000000000000007c
> 08 0000000000004000 0000000000003940 00000000001d4810 0000000001a3ff40
> 0c 0000000040000084 0000000000000000 0000000000000000 0000000000000000
> 10 0000000000000000 0000000000000000 0000000000000000 0000000000000000
> 14 0000000000c00000 0000000000000008 0000000000000000 0000000000000000
> 18 0000000000000000 0000000000000000 0000000000000000 0000000000000000
> 1c 0000000000219620 00000000001e3eb0 0000000000219620 00000000001e3de0
> Special Regs:
> %IV: 00000700 %CR: 20000084 %XER: 00000000 %DSISR: 00000000
> %SRR0: 0000000000003940 %SRR1: 0000000000083002
> %LR: 000000000020a0a4 %CTR: 0000000000003940
> %DAR: 0000000000000000
> Virtual PID = 0
> ok
> 0 >
>
> After some investigation, my colleague Gustavo Duarte discover that the
> problem is caused by grub_file_filters_enabled. Its initial value isn't
> zero:
> grub_file_filters_enabled[0]@0x219614 0x0
> grub_file_filters_enabled[1]@0x219618 0x0
> grub_file_filters_enabled[2]@0x21961c 0x0
> grub_file_filters_enabled[3]@0x219620 0x3940
>
>
> Using objdump I noticed that this variable is the last one from the bss
> section:
> $objdump -t grub-core/kernel.exec | sort
> ...
> 00218d14 l O .bss 00000004 count.2347
> 00218d18 l O .bss 00000100 buf.1909
> 00218e18 l O .bss 00000100 linebuf
> 00218f18 g O .bss 00000100 grub_errmsg
> 00219018 g O .bss 00000010 grub_file_filters_all
> 00219028 g O .bss 00000010 grub_file_filters_enabled
> 00219038 g .bss 00000000 _end
>
> It seems that startup.S for powerpc skips the last bytes, so I made a
> patch to fix it. Tried again and the problem was gone:
> grub_file_filters_enabled[0]@0x219614 0x0
> grub_file_filters_enabled[1]@0x219618 0x0
> grub_file_filters_enabled[2]@0x21961c 0x0
> grub_file_filters_enabled[3]@0x219620 0x0
>
As discussed on IRC this patch was wrong. The real problem was handling
unaligned BSS. Fixed in trunk now.
>
>
> Best regards!
>
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel
>
prev parent reply other threads:[~2013-07-16 5:47 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-15 19:12 [PATCH] powerpc: fix startup bss cleaning Paulo Flabiano Smorigo/Brazil/IBM
2013-07-16 5:47 ` Vladimir 'φ-coder/phcoder' Serbinenko [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=51E4DE77.40402@gmail.com \
--to=phcoder@gmail.com \
--cc=grub-devel@gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).