Syslinux - Jan 2014 - After USB boot problems on Gigabyte GA-M55Plus-S3G

the closest i have gotten to a consistent way to test a MS-DOS filesystem
setup is:

dd if=/dev/zero of=binary.img bs=1M count=500
i="$(losetup -f --show binary.img )"
parted binary.img mklabel msdos -s -m
dd if=/usr/lib/syslinux/mbr.bin of="${i}"
parted binary.img mkpart primary -a optimal -s -m 0% 100%
parted binary.img set 1 boot on
mkfs.ext4 $(kpartx -savu "${i}" | awk 'NR==1{print
"/dev/mapper/"$3 }' )
mount $(kpartx -savu "${i}" | awk 'NR==1{print
"/dev/mapper/"$3 }' ) /mnt
extlinux --install /mnt/boot
cp /usr/lib/syslinux/vesamenu.c32 /mnt/boot
cat > /mnt/boot/extlinux.conf <<EOF
UI vesamenu.c32
DEFAULT linux
LABEL linux
LINUX /boot/bzImage
APPEND root=/dev/sda1 init=/bin/ash
EOF
umount /mnt
kpartx -d "${i}"
losetup -d "${i}"
kvm binary.img

works
but not with gpt
-chris graff (dean)


On Tue, Jan 21, 2014 at 11:07 AM, Thomas Schmitt <scdbackup at gmx.net>
wrote:
> Hi,
>
> hpa wrote:
> > LBA = (C * H' * S') + (H * S') + (S - 1)
> > [...]
> > Start LBA       63 = CHS    0   1   1
> > End   LBA 15794175 = CHS  982 254  63
> > If LBA 63 = CHS 0/1/1 then we know S'=62, but that is completely
> > inconsistent with the ending sector being 63.
>
> Wouldn't that be S'=63 ?
> 63 = (0 * H' * 63) + (1 * 63) + (1 - 1)
>
> Whatever, the stick producers seem to take the same freedom
> as needed when the disk size exceeds 1023*255*63 :
> Start LBA plus blocksize does not need to match end CHS.
>
> Ady's understanding seems not uncommon, that the end CHS address
> shall indicate H' and S' by (H + 1) and S.
> I wonder if this is specified anywhere.
> (It is equivalent to cylinder alignment of the partition end.)
>
>
> > Fortunately geometry is becoming a fading problem.  We're dealing
with
> > an old board and BIOS here.
>
> My own hardware is of similar age.
>
> I am getting more and more pessimistic with the idea to
> propose at least one "normal" MS-DOS filesystem setup.
> If not Ady comes to the rescue, that is.
>
> It seems so unfair to leave the users alone with mad partitioning
> and naive boards. :o)
>
>
> Have a nice day :)
>
> Thomas
>
> _______________________________________________
> Syslinux mailing list
> Submissions to Syslinux at zytor.com
> Unsubscribe or set options at:
> http://www.zytor.com/mailman/listinfo/syslinux
> Please do not send private replies to mailing list traffic.
>
>

btw, that works with mkfs.vfat as well. just have to use syslinux with a
syslinux.cfg file instead of extlinux with an extlinux.conf.


On Tue, Jan 21, 2014 at 11:58 AM, Dean Graff <graff97 at gmail.com> wrote:
> the closest i have gotten to a consistent way to test a MS-DOS filesystem
> setup is:
>
> dd if=/dev/zero of=binary.img bs=1M count=500
> i="$(losetup -f --show binary.img )"
> parted binary.img mklabel msdos -s -m
> dd if=/usr/lib/syslinux/mbr.bin of="${i}"
> parted binary.img mkpart primary -a optimal -s -m 0% 100%
> parted binary.img set 1 boot on
> mkfs.ext4 $(kpartx -savu "${i}" | awk 'NR==1{print
"/dev/mapper/"$3 }' )
> mount $(kpartx -savu "${i}" | awk 'NR==1{print
"/dev/mapper/"$3 }' ) /mnt
> extlinux --install /mnt/boot
> cp /usr/lib/syslinux/vesamenu.c32 /mnt/boot
> cat > /mnt/boot/extlinux.conf <<EOF
> UI vesamenu.c32
> DEFAULT linux
> LABEL linux
> LINUX /boot/bzImage
> APPEND root=/dev/sda1 init=/bin/ash
> EOF
> umount /mnt
> kpartx -d "${i}"
> losetup -d "${i}"
> kvm binary.img
>
> works
> but not with gpt
> -chris graff (dean)
>
>
> On Tue, Jan 21, 2014 at 11:07 AM, Thomas Schmitt <scdbackup at
gmx.net>wrote:
>
>> Hi,
>>
>> hpa wrote:
>> > LBA = (C * H' * S') + (H * S') + (S - 1)
>> > [...]
>> > Start LBA       63 = CHS    0   1   1
>> > End   LBA 15794175 = CHS  982 254  63
>> > If LBA 63 = CHS 0/1/1 then we know S'=62, but that is
completely
>> > inconsistent with the ending sector being 63.
>>
>> Wouldn't that be S'=63 ?
>> 63 = (0 * H' * 63) + (1 * 63) + (1 - 1)
>>
>> Whatever, the stick producers seem to take the same freedom
>> as needed when the disk size exceeds 1023*255*63 :
>> Start LBA plus blocksize does not need to match end CHS.
>>
>> Ady's understanding seems not uncommon, that the end CHS address
>> shall indicate H' and S' by (H + 1) and S.
>> I wonder if this is specified anywhere.
>> (It is equivalent to cylinder alignment of the partition end.)
>>
>>
>> > Fortunately geometry is becoming a fading problem.  We're
dealing with
>> > an old board and BIOS here.
>>
>> My own hardware is of similar age.
>>
>> I am getting more and more pessimistic with the idea to
>> propose at least one "normal" MS-DOS filesystem setup.
>> If not Ady comes to the rescue, that is.
>>
>> It seems so unfair to leave the users alone with mad partitioning
>> and naive boards. :o)
>>
>>
>> Have a nice day :)
>>
>> Thomas
>>
>> _______________________________________________
>> Syslinux mailing list
>> Submissions to Syslinux at zytor.com
>> Unsubscribe or set options at:
>> http://www.zytor.com/mailman/listinfo/syslinux
>> Please do not send private replies to mailing list traffic.
>>
>>
>

Hi,

Dean Graff wrote:
> the closest i have gotten to a consistent way to test a MS-DOS filesystem
> setup is:
> [...]
> parted binary.img mklabel msdos -s -m
> [...]
> mkfs.ext4 $(kpartx -savu "${i}" | awk 'NR==1{print
"/dev/mapper/"$3 }' )
Wow. This is nearly as ugly as a xorriso run to produce an
isohybrid image.

Even if we leave out the image file preparation and the part
after mkfs.ext4 (or mkfs.vfat), i still doubt that a prescription
of this complexity will be of much help for a user who is
riddling why the USB stick does not boot.


Have a nice day :)

Thomas