on BIOS problems with disks larger than 2 TB

[Andriy Gapon]

On 12/08/2016 22:18, John Baldwin wrote:
> Hmm, I'm not sure how easy it is to handle this case (i.e. how do you know
> if an LBA beyond the size is really legit due to truncation vs coming from
> corrupted metadata).  Related is that tsoome's bcache stuff wants to know
> where the end of the disk is (to avoid reading off the end), so just
> ignoring the size is not easy.

One idea that I have in mind but haven't really explored yet is for GPT
formatted disks.  Basically, if a GPT label hints that the disk size is larger
than what BIOS reports, then we could try to read a backup label and if it
matches what we expect, then we could adjust the size.

Hmm, I think I recall that a long time ago some BIOSes used to do something
similar with MBR :-)

-- 
Andriy Gapon