reth 2.0: debug_traceCall{,Many} prestateTracer diffMode shows phantom gas credits when gasPrice > 0

[davidberiro]

Describe the bug

reth v2.0.0 appears to have a regression in simulation tracing endpoints that set
cfg_env.disable_fee_charge = true, notably:

• debug_traceCall
• debug_traceCallMany

When these are used with prestateTracer and diffMode: true, and the traced call
specifies gasPrice > 0 and an explicit gas > 0, the returned state diff can show:

• the caller balance increasing by a gas-price-scaled amount
• the beneficiary / coinbase balance increasing as well

This is a phantom balance change during simulation and should not happen.

This does not appear to be a reth DB issue. The root cause is upstream in
revm-handler and has been fixed here:

• upstream PR: (fix(handler): skip gas reimbursement and beneficiary reward when fee charge is disabled bluealloy/revm#3559)

The issue is that calculate_caller_fee respects disable_fee_charge, but
reimburse_caller and reward_beneficiary still ran unconditionally in the affected
revm-handler version, which causes gas-related balances to be credited even though the
upfront charge was skipped.

reth v2.0.0 resolves revm-handler 17.0.0, which appears affected.
For comparison, reth v1.11.3 resolved revm-handler 15.0.0.

Additional context

This seems best tracked in reth so users hitting it through reth RPC can find the
upstream fix and so reth can update once a revm release includes:

• (fix(handler): skip gas reimbursement and beneficiary reward when fee charge is disabled bluealloy/revm#3559)

Steps to reproduce

1. Run reth v2.0.0.
2. Call debug_traceCall or debug_traceCallMany with:
   • tracer: "prestateTracer"
   • tracerConfig: { "diffMode": true }
   • a transaction/call object with explicit gas > 0
   • gasPrice > 0
3. Inspect the returned diff.
4. Observe that the caller balance increases by a gas-price-scaled amount instead of
   remaining unchanged for simulation.

The bug disappears when gasPrice = 0, which is consistent with the upstream
revm-handler fee-handling regression.

Node logs

Platform(s)

Mac (Apple Silicon)

Container Type

Not running in a container

What version/commit are you on?

Reth Version: 2.0.0
Commit SHA: eb4c15e
Build Timestamp: 2026-04-07T12:54:52.441107000Z
Build Features: asm_keccak,jemalloc,keccak_cache_global,min_debug_logs,otlp,otlp_logs
Build Profile: maxperf

What database version are you on?

Current database version: 2
Local database version: 2

Which chain / network are you on?

mainnet

What type of node are you running?

Full via --full flag

What prune config do you use, if any?

No response

If you've built Reth from source, provide the full command you used

No response

Code of Conduct

• I agree to follow the Code of Conduct

[mattsse]

can you provide some example request/responses

[davidberiro]

can you provide some example request/responses

curl http://127.0.0.1:18545 -X POST -H "Content-Type: application/json" --data '{"method":"debug_traceCallMany","params":[[{"transactions":[{"from": "0x3213213213213213213213213213213213213213", "to": "0x3213213213213213213213213213213213213213", "gasPrice": "0xE8D4A51000", "gas":"0xAC6BE", "data":"0x"}]}],{"blockNumber": "pending"},{"tracer":"prestateTracer", "tracerConfig":{"diffMode":true}}],"id":1,"jsonrpc":"2.0"}' | jq

  "jsonrpc": "2.0",
  "id": 1,
  "result": [
    [
      {
        "post": {
          "0x3213213213213213213213213213213213213213": {
            "balance": "0x982745498996000",
            "nonce": 1
          },
          "0xb20cb55edf81bacfd271f5468e7fc56a3ea4510b": {
            "balance": "0x2b2355277cbe2f2fb"
          }
        },
        "pre": {
          "0x3213213213213213213213213213213213213213": {
            "balance": "0x0"
          },
          "0xb20cb55edf81bacfd271f5468e7fc56a3ea4510b": {
            "balance": "0x2b1eaba2c4b1dac6b"
          }
        }
      }
    ]
  ]
}