Grub4dos problem with Syslinux 4

Discussion/announcements about test/beta releases of UBCD will be posted here.

Moderators: Icecube, StopSpazzing

Post Reply
Message
Author
Victor Chew
Posts: 1359
Joined: Mon Feb 21, 2005 10:59 pm
Contact:

Grub4dos problem with Syslinux 4

#1 Post by Victor Chew » Sun Sep 19, 2010 8:25 pm

Looks like grub4dos "chainloader" command is broken on syslinux 4. Trying to execute:

Code: Select all

chainloader /boot/isolinux/isolinux.bin || chainloader +1


gives:

Code: Select all

Error 13: Invalid or unsupported executable format


Any workaround for this?

Icecube
Posts: 1278
Joined: Fri Jan 11, 2008 2:52 pm
Contact:

Re: Grub4dos problem with Syslinux 4

#2 Post by Icecube » Mon Sep 20, 2010 10:56 am

grub4dos uses some magic bytes to determine if the chainloaded file is isolinux.bin or not.
This magic bytes are not the same between all releases. I will ask the grub4dos developers to support the newer version too.
Download Ultimate Boot CD v5.0: http://www.ultimatebootcd.com/download.html
Use Parted Magic for handling all partitioning task: http://partedmagic.com/

Icecube
Posts: 1278
Joined: Fri Jan 11, 2008 2:52 pm
Contact:

Re: Grub4dos problem with Syslinux 4

#3 Post by Icecube » Wed Sep 22, 2010 12:15 pm

Download Ultimate Boot CD v5.0: http://www.ultimatebootcd.com/download.html
Use Parted Magic for handling all partitioning task: http://partedmagic.com/

Victor Chew
Posts: 1359
Joined: Mon Feb 21, 2005 10:59 pm
Contact:

Re: Grub4dos problem with Syslinux 4

#4 Post by Victor Chew » Sat Sep 25, 2010 3:07 pm

Thanks! Will try.

kcarney
Posts: 52
Joined: Tue Nov 24, 2009 9:22 am

Re: Grub4dos problem with Syslinux 4

#5 Post by kcarney » Tue Dec 21, 2010 1:42 pm

I believe this is broken for USB switching from grub4dos menu to syslinux

Cannot chainload ISOLINUX from a non-CDROM device.
Partition table not recognized(boot_drive=0x80, err=1)

Error 43: The BPB hidden_sectors should not be zero for a hard disk boot sector



Icecube
Posts: 1278
Joined: Fri Jan 11, 2008 2:52 pm
Contact:

Re: Grub4dos problem with Syslinux 4

#6 Post by Icecube » Tue Dec 21, 2010 2:16 pm

Did you had problems with the same USB stick before?
Did you reformat/repartitioned it in the meanwhile?

I think, I had the same issue (Error 43: The BPB hidden_sectors should not be zero for a hard disk boot sector) in the past.
Syslinux doesn't care about that field, but grub4dos complains about it. I patched the byte manually. I think your partition will probably be a logical partition.

I think I confirmed the "problem" with running boot_info_script. You can do that from Parted Magic.
Download Ultimate Boot CD v5.0: http://www.ultimatebootcd.com/download.html
Use Parted Magic for handling all partitioning task: http://partedmagic.com/

kcarney
Posts: 52
Joined: Tue Nov 24, 2009 9:22 am

Re: Grub4dos problem with Syslinux 4

#7 Post by kcarney » Tue Dec 21, 2010 2:22 pm

I think you may be right, something seems weird in the way it is formatted. There are 0 hidden sectors when I believe there should be 63. I'll give the script a try and see what it says.

Any way to bypass the complaint grub4dos has? In a few hours I haven't found any on my own.

Post Reply