Subject: [parted] Problem with msdos mbr creation

From: Lukasz Majewski <[email-masked]>
Date: Wed, 1 Feb 2017 11:28:03 +0100

Dear All,

My parted version is 3.2. OS: Linux GNU Debian 8.6

For one of my embedded systems (arm based one) I do use parted to create
bootable SD card.

parted -s $DRIVE mklabel msdos

First, I do clean up the first 1MiB of SD card:

dd if=/dev/zero of=$DRIVE bs=1024 count=1024

The problem is that parted is generating following code from the very
beginning of the MBR:

00000000  FA B8 00 10  8E D0 BC 00   B0 B8 00 00  8E D8 8E C0
00000010  FB BE 00 7C  BF 00 06 B9   00 02 F3 A4  EA 21 06 00
00000020  00 BE BE 07  38 04 75 0B   83 C6 10 81  FE FE 07 75
00000030  F3 EB 16 B4  02 B0 01 BB   00 7C B2 80  8A 74 01 8B

What is the purpose of this code? Why is has been put there?

Such data in this place fools the ROM bootloader and hangs the board.

Also, fdisk (from util-linux 2.25.2) when is creating "dos" partition
table is not writing such data.

Best regards,

Lukasz Majewski

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