In December, I downloaded Precision T5820 bios v 2.0.1 from the Dell support site, and applied it to a few systems (with no obvious issue). Looking at the same page today
the latest bios is version 1.13.0 (from October). Was 2.0.1 withdrawn? Is downgrading recommended? I can't find any details.
I understand BIOS version 2.0.1 for the Precision Tower 5820 is related to DSA-2019-147. This security advisory targets a huge number of CVEs, so it is a large BIOS update. I would not be surprised if it has been removed by Dell because some customers found problems on it. While here, removal of this BIOS version on your platform explains why there are so many systems, whose update should have arrived on december, that have not received it yet.
My advice would be staying at the current BIOS level, if it works for you, instead of downgrading. In a few weeks there will be a fixed BIOS release for our workstations. As you say, it has no obvious issues on your Precision.
I am also having an issue with BIOS version 2.0.1 on the 5820 workstation. It is indeed unable to roll-back to ANY previous version I've been able to find on Dell's site.
So far, the issue I am faced with is BSOD everytime windows gets loaded to the logon screen. The BSOD are numerous, all stating page fault errors, etc. The system was running fine until I discovered it had been updated to 2.0.1 and hasn't booted since.
I've submitted a ticket request, and will get back to you guys with what I hear back.
Goodluck with this one..
After a lengthy troubleshooting session with support, Dell has sent me a new motherboard for my machine due to being unable to roll-back the BIOS version from 2.0.1 to anything previous.. I will advise if the new motherboard corrects the BSOD errors for anyone else who may have this issue.
I would try one of these procedures before changing the motherboard on your workstation, it is not clear to me these emergency procedures follow the signed firmware update guidelines:
DSA-2019-147 has a lot of critical security-related changes, so Dell probably got rid of the old digital certificate used for BIOS signed updates:
As a consequence, your workstation does not recognise as valid firmware previous releases of the BIOS for the Precision Tower 5820. It is a good decision and, in my humble opinion, one of the best security features provided by firmware following the NIST SP800-147 protection guideline. Just think of the risk of a BIOS being downgraded to a vulnerable version.