Re: New mode DM-Verity error handling

[Mike Snitzer]

On Thu, Jun 18 2020 at  2:56am -0400,
JeongHyeon Lee <jhs2.lee@xxxxxxxxxxx> wrote:

> Hello, Dear devcice-mapper maintainers.
> 
> I'm JeongHyeon Lee, work in Samsung. I'm chage of DM-Verity feature with 
> Mr. sunwook eom.
> I have a patch or suggestion about DM-Verity error handling.
> 
> Our device (smart phone) need DM-Verity feature. So I hope there is new 
> mode DM-Verity error handling.
> This new mode concept is When detect corrupted block, will be go to panic.
> 
> Because our team policy is found device DM-Verity error, device will go 
> panic.
> And then analyze what kind of device fault (crash UFS, IO error, DRAM 
> bit flip etc)
> 
> In addition to the smart phone, I would like to have an option that 
> users or administrators can use accordingly.
> There are patch contents in the attachment. I would really appreciate it 
> if you could check it.
> 
> I will look forward to hearing from yours.
> Thank you :)
> 

I do not accept that panicing the system because of verity failure is
reasonable.

In fact, even rebooting (via DM_VERITY_MODE_RESTART) looks very wrong.

The device should be put in a failed state and left for admin recovery.

Mike