Re: GRUB and the risk of block list corruption in extX

[Andrey Borzenkov]

В Thu, 07 Feb 2013 11:47:33 +0100
Martin Wilck <address@hidden> пишет:

> Hello,
> 
> this is a question about the long-running topic of installing GRUB in
> partitions or partitionless disks.
> 

Here is example how using filesystem blocklists may lead to unbootable
system without any extX corruption involved.

- user sets up multiboot system with Windows as primary bootloader
- standard technique to add Linux loaders has always been - copy
  partition boot sector and "launch" it from Windows loader
- user copies Linux partition boot sector which points to core.imng
  absolute disk position
- user updates grub in Linux. core.img is rewritten and its position
  changes
- next time user tries to boot Linux (s)he gets blinking cursor

So *any* third party bootloader that relies on being able to
"chainload" *copy* of boot sector will give you the same issue.