* [9fans] bug report : disk/fdisk
@ 2023-06-10 14:51 ibrahim via 9fans
0 siblings, 0 replies; only message in thread
From: ibrahim via 9fans @ 2023-06-10 14:51 UTC (permalink / raw)
[-- Attachment #1: Type: text/plain, Size: 959 bytes --]
After creating an image file with :
the resulting partition table in the mbr is buggy :
the chs values in the mbr are incompatible with bios.
bios uses the formula (c*H+h)*S+s-1 to calculate the lba values with H=256, S=63 while c (cylinder), h(head), s(sector) are the values from chs entries in the mbr partition table.
disk/fdisk uses the same formula while setting H=64, S=32.
If you write this image to real Hardware (HDD, USB-Sticks) some bios won't boot from such media especially if your boot drive has a size less than 8GB cause for media with sizes less than this size some bios'es use CHS addressing and some verify that sector id's from chs and lba are equal.
Delivery options: https://9fans.topicbox.com/groups/9fans/subscription
[-- Attachment #2: Type: text/html, Size: 1724 bytes --]
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2023-06-10 14:51 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-06-10 14:51 [9fans] bug report : disk/fdisk ibrahim via 9fans
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).