jailed validators (from downtime) attempt to jail every block

[Reecepbcups]

Built into #160, when a validator is jailed the logic continues to try and set jailed state.

There does not seem to be a technical issue with it, but jailing a validator every block for an entire unbonding period is no bueno

Solutions

• Fix the issue so there is only a single 1 off jail event (ideal). Probably some key / power index to set to make it happy
• Instant unbond jailed validators (and removal) rather than re-jailing

[alexanderbez]

@Reecepbcups what makes it attempt to re-jail every block? Do we need to simply need to mark the validator as jailed? Or perhaps, there is an x/staking or x/slashing method we can override?

[Reecepbcups]

@alexanderbez here is where it's sort of stemming from: #160 (comment)

Issue: x/staking panics if pulling a jailed validator from the validator set on ApplyValUpdates (staking endblock). So we have to override the validator from being jailed so that the last ApplyValUpdates can be set as they begin unbonding. We can't just delete the validator outright (DeleteLastValidatorPower) from the CometBFT updates since that would be 2x abci.ValUpdate updates (x/staking) from a single val, resulting in a consensus panic

I think a solution here is yet another cache where:

• Block 1 x/poa: we set the val.Jailed = false, add to cache.
• Block 1 x/staking / x/slashing, jails the validator & slashes
• Block 2 x/poa: sees a val in the toJail cache, and deletes power / sets to real Jail
• Block 2 x/staking: val is really jailed, abci persisted

pretty much a delay of jail by h+1 rather than at h. This way x/staking and x/slashing can handle all their logic as normal, and so teams do not have to fork the SDK / staking

[Reecepbcups]

Update, removing this from the upstream SDK would solve the issue. Unsure why we panic vs continuing since we iter all validators anyways.

func (k Keeper) ApplyAndReturnValidatorSetUpdates(ctx context.Context) (updates []abci.ValidatorUpdate, err error) {
               ...
		if validator.Jailed {
			// panic("should never retrieve a jailed validator from the power store") // replace this line w/ continue
			continue
		}
		...
}

cosmos/cosmos-sdk#20059

[alexanderbez]

Yup, makes sense. Good catch and patch.

[Reecepbcups]

resolved in #165