v2open: dont rely on ordering of interprocess messages

Originally I (incorrectly?) assumed that since TX_COMMITMENT_SIGNED
always came before TX_SIGNATURES, we would always receive a response
from openchannel_update (w/ commitment_secured = true) before getting
notification of receipt of the peer's signatures.

But it's observable in the logs of hung tests that this in fact is a
wrong assumption -- the notification for the tx_sigs arrives at our
spender plugin before the callback from our openchannel_update RPC.

This mis-ordering causes a hang.

Luckily we're pretty much setup to handle this race already w/ states
etc, minus actually calling the method advance the plot in case we're
ready.

2022-07-26T05:37:59.4529095Z lightningd-1 2022-07-26T05:10:07.395Z DEBUG   035d2b1192dfba134e10e540875d366ebc8bc353d5aa766b80c090b39c3a5d885d-dualopend-chan#2: peer_in WIRE_COMMITMENT_SIGNED
2022-07-26T05:37:59.4530452Z lightningd-1 2022-07-26T05:10:07.396Z DEBUG   035d2b1192dfba134e10e540875d366ebc8bc353d5aa766b80c090b39c3a5d885d-hsmd: Got WIRE_HSMD_VALIDATE_COMMITMENT_TX
2022-07-26T05:37:59.4530719Z lightningd-1 2022-07-26T05:10:07.396Z DEBUG   hsmd: Client: Received message 35 from client
2022-07-26T05:37:59.4531386Z lightningd-1 2022-07-26T05:10:07.396Z DEBUG   035d2b1192dfba134e10e540875d366ebc8bc353d5aa766b80c090b39c3a5d885d-dualopend-chan#2: billboard: channel open: commitment received, sending to lightningd to save
2022-07-26T05:37:59.4531856Z lightningd-1 2022-07-26T05:10:07.398Z DEBUG   035d2b1192dfba134e10e540875d366ebc8bc353d5aa766b80c090b39c3a5d885d-dualopend-chan#2: peer_in WIRE_TX_SIGNATURES
>>> 2022-07-26T05:37:59.4532553Z lightningd-1 2022-07-26T05:10:07.400Z DEBUG   plugin-spenderp: mfc 60:`openchannel_peer_sigs` notice received for channel 9d145e763f08ee6f715ba7677f869cbb9580c7406f4d0b0ff3a0987efe501e13 <<<< THIS ONE WAS ASSUMED TO COME AFTER openchannel_update (next line)
2022-07-26T05:37:59.4533048Z lightningd-1 2022-07-26T05:10:07.400Z DEBUG   plugin-spenderp: mfc 60, dest 0: openchannel_update 035d2b1192dfba134e10e540875d366ebc8bc353d5aa766b80c090b39c3a5d885d returned.
2022-07-26T05:37:59.4554292Z lightningd-1 2022-07-26T05:10:07.400Z DEBUG   plugin-spenderp: mfc 60: parallel `openchannel_update`.
2022-07-26T05:37:59.4555485Z lightningd-1 2022-07-26T05:10:07.400Z DEBUG   plugin-spenderp: mfc 60: funding tx 50425e20dbf0ca6fe112a8811b8048edb5bfa8d2922079668c5f353b859b45cb
2022-07-26T05:37:59.4557934Z lightningd-1 2022-07-26T05:10:07.508Z DEBUG   0266e4598d1d3c415f572a8488830b60f7e744ed9235eb0b1ba93283b315c03518-hsmd: Got WIRE_HSMD_CUPDATE_SIG_REQ
2022-07-26T05:37:59.4558244Z lightningd-1 2022-07-26T05:10:07.508Z DEBUG   hsmd: Client: Received message 3 from client
2022-07-26T05:37:59.4558738Z lightningd-3 2022-07-26T05:11:03.234Z DEBUG   0266e4598d1d3c415f572a8488830b60f7e744ed9235eb0b1ba93283b315c03518-gossipd: seeker: startup peer finished
2022-07-26T05:37:59.4559209Z lightningd-3 2022-07-26T05:11:03.234Z DEBUG   0266e4598d1d3c415f572a8488830b60f7e744ed9235eb0b1ba93283b315c03518-gossipd: seeker: state = PROBING_SCIDS Seeking scids 1 - 105

(The last 2 log messages (from a different node) are >1min after the last
log line from lightning-1, because lightning-1 hung)

Hacked lightningd up to test this (such that notification always sent
before the RPC response, works as intended w/ patch)
This commit is contained in:
niftynei 2022-07-26 20:00:07 -05:00 committed by Rusty Russell
parent 2c2bcc8eb4
commit 79a76a96f7

View File

@ -621,10 +621,9 @@ funding_transaction_established(struct multifundchannel_command *mfc)
/* If all we've got is v2 destinations, we're just waiting
* for all of our peers to send us their sigs.
* That callback triggers separately, so we just return
* a 'still pending' here */
* Let's check if we've gotten them yet */
if (dest_count(mfc, FUND_CHANNEL) == 0)
return command_still_pending(mfc->cmd);
return check_sigs_ready(mfc);
/* For any v1 destination, we need to update the destination
* outnum with the correct outnum on the now-known