This allows us to reference assumeutxo configuration by blockhash as
well as height; this is helpful in future changes when we want to
reference assumeutxo configurations before the block index is loaded.
Add new PeerManagerImpl::TryDownloadingHistoricalBlocks method and use it to
request background chain blocks in addition to blocks normally requested by
FindNextBlocksToDownload.
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
Co-authored-by: James O'Beirne <james.obeirne@gmail.com>
96b3f2dbe4395ca55cfdd58c8f9f9bd7ca163983 test: add unit test coverage for Python ECDSA implementation (Sebastian Falbesoner)
Pull request description:
This PR adds missing unit test coverage for the Python ECDSA implementation, which should be useful for detecting potential problems early whenever changes in the test framework's Python implementation of secp256k1 are made (e.g. #26222). Note that right now we don't call `ECPubKey.verify_ecdsa` anywhere in our tests, so we wouldn't notice if it is broken at some point.
To keep it simple, the already existing unit test for Schnorr signatures is extended to also check ECDSA signatures. For that purpose, the dictionary storing private-key/public-key entries use their legacy types `ECKey/ECPubKey` instead of bare byte-arrays, and for Schnorr signing/verification the necessary conversions (ECKey -> bare private key, ECPubKey -> x-only pubkey) is done later when needed. To avoid code duplication, a helper function `random_bitflip` for damaging signatures is introduced.
The unit test can be run by either calling it for this single module:
`$ python3 -m unittest ./test/functional/test_framework/key.py`
or simply running `$ ./test/functional/test_runner.py` which calls all test framework module's unit tests at the start (see TEST_FRAMEWORK_MODULES list).
ACKs for top commit:
achow101:
ACK 96b3f2dbe4395ca55cfdd58c8f9f9bd7ca163983
sipa:
utACK 96b3f2dbe4395ca55cfdd58c8f9f9bd7ca163983
stratospher:
tested ACK 96b3f2d.
Tree-SHA512: b993f25b843fa047376addda4ce4b0f15750ffba926528b5cca4c5f99b9af456206f4e8af885d25a017dddddf382ddebf38765819b3d16a3f28810d03b010808
d8041d4e042957660827313951b18c8dd9a99a16 blockstorage: Return on fatal undo file flush error (TheCharlatan)
f0207e00303a1030eca795ede231e3c0d94df061 blockstorage: Return on fatal block file flush error (TheCharlatan)
5671c15f4520c6dc20e0805fd0b06157ff94bcd7 blockstorage: Mark FindBlockPos as nodiscard (TheCharlatan)
Pull request description:
The goal of this PR is to establish that fatal blockstorage flush errors should be treated as errors at their call site.
Prior to this patch `FlushBlockFile` may have failed without returning in `Chainstate::FlushStateToDisk`, leading to a potential write from `WriteBlockIndexDB` that may refer to a block that is not fully flushed to disk yet. By returning if either `FlushUndoFile` or `FlushBlockFile` fail, we ensure that no further write operations take place that may lead to an inconsistent database when crashing. Add `[[nodiscard]]` annotations to them such that they are not ignored in future.
Functions that call either `FlushUndoFile` or `FlushBlockFile`, need to handle these extra abort cases properly. Since `Chainstate::FlushStateToDisk` already produces an abort error in case of `WriteBlockIndexDB` failing, no extra logic for functions calling `Chainstate::FlushStateToDisk` is required.
Besides `Chainstate::FlushStateToDisk`, `FlushBlockFile` is also called by `FindBlockPos`, while `FlushUndoFile` is only called by `FlushBlockFile` and `WriteUndoDataForBlock`. For both these cases, the flush error is not further bubbled up. Instead, the error is logged and a comment is provided why bubbling up an error would be less desirable in these cases.
---
This pull request is part of a larger effort towards improving the shutdown / abort / fatal error handling in validation code. It is a first step towards implementing proper fatal error return type enforcement similar as proposed by theuni in this pull request [comment](https://github.com/bitcoin/bitcoin/pull/27711#issuecomment-1563561502). For ease of review of these critical changes, a first step would be checking that `AbortNode` leads to early and error-conveying returns at its call site. Further work for enforcing returns when `AbortNode` is called is done in https://github.com/bitcoin/bitcoin/pull/27862.
ACKs for top commit:
stickies-v:
re-ACK d8041d4
ryanofsky:
Code review ACK d8041d4e042957660827313951b18c8dd9a99a16
Tree-SHA512: 47ade9b873b15e567c8f60ca538d5a0daf32163e1031be3212a3a45eb492b866664b225f2787c9e40f3e0c089140157d8fd1039abc00c7bdfeec1b52ecd7e219
e3720bca398820038b3e97f467adb2c45ef9ef5f net: Simplify v2 recv logic by decoupling AAD from state machine (Tim Ruffing)
b0f5175c044df956c0f07f540706d457c4912856 net: Drop v2 garbage authentication packet (Tim Ruffing)
Pull request description:
Note that this is a breaking change, see also https://github.com/bitcoin/bips/pull/1498
The benefit is a simpler implementation:
- The protocol state machine does not need separate states for garbage authentication and version phases.
- The special case of "ignoring the ignore bit" is removed.
- The freedom to choose the contents of the garbage authentication packet is removed. This simplifies testing.
ACKs for top commit:
naumenkogs:
ACK e3720bca398820038b3e97f467adb2c45ef9ef5f
sipa:
ACK e3720bca398820038b3e97f467adb2c45ef9ef5f. Re-ran the v2 transport fuzzer overnight.
ajtowns:
ACK e3720bca398820038b3e97f467adb2c45ef9ef5f - simpler and more flexible, nice
achow101:
ACK e3720bca398820038b3e97f467adb2c45ef9ef5f
Sjors:
utACK e3720bca398820038b3e97f467adb2c45ef9ef5f
theStack:
Code-review ACK e3720bca398820038b3e97f467adb2c45ef9ef5f
Tree-SHA512: 16600ed868c8a346828de075c4072e37cf86440751d08ab099fe8b58ff71d8b371a90397d6a4247096796db68794275e7e0403f218859567d04838e0411dadd6
b5a962564eb15075e4e2a7bc0c235a56fa998ac3 tests: Use manual bumps instead of bumpfee for resendwallettransactions (Andrew Chow)
Pull request description:
Bumpfee will try to increase the entire package to the target feerate, which causes repeated bumpfees to quickly shoot up in fees, causing intermittent failures when the fee is too large. We don't care about this property, just that the child is continuously replaced until we observe it's position in mapWallet is before its parent. Instead of using bumpfee, we can create raw transactions which have only pay (just above) the additional incremental relay fee, thus avoiding this problem.
Fixes#28491
ACKs for top commit:
kevkevinpal:
ACK [b5a9625](b5a962564e)
mzumsande:
Code review ACK b5a962564eb15075e4e2a7bc0c235a56fa998ac3
pablomartin4btc:
ACK b5a962564eb15075e4e2a7bc0c235a56fa998ac3 -> adding the `try_rpc` to avoid (skip) any possible failure around the manual bump fee (if we ever reach it as [explained](https://github.com/bitcoin/bitcoin/pull/28540#issuecomment-1737648048)) makes a lot of sense as the spirit of the test is the tx (child before parent) sort in the `mapWallet` (as also [explained](https://github.com/bitcoin/bitcoin/issues/28491#issuecomment-1736161363)).
MarcoFalke:
lgtm ACK b5a962564eb15075e4e2a7bc0c235a56fa998ac3
Tree-SHA512: f184f11c73be0c30753181901f51a3b4b9c4135e0c4681e9f4ca94692c49bac15c91683c85266a2124333c8593e9919bfd9102724616faab299740f2eb98741f
262ab8ef7860d43cebc9d04721e3a075b4edf06e Add package evaluation fuzzer (Greg Sanders)
Pull request description:
This fuzzer target caught the issue in https://github.com/bitcoin/bitcoin/pull/28251 within 5 minutes on master branch, and an additional issue which I've applied a preliminary patch to cover.
Fuzzer target does the following:
1) Picks mempool confgs, including max package size, count, mempool size, etc
2) Generates 1 to 26 transactions with arbitrary coins/fees, the first N-1 spending only confirmed outpoints
3) Nth transaction, if >1, sweeps all unconfirmed outpoints in mempool
4) If N==1, it may submit it through single-tx submission path, to allow for more interesting topologies
5) Otherwise submits through package submission interface
6) Repeat 1-5 a few hundred times per mempool instance
In other words, it ends up building chains of txns in the mempool using parents-and-children packages, which is currently the topology supported on master.
The test itself is a direct rip of tx_pool.cpp, with a number of assertions removed because they were failing for unknown reasons, likely due to the notification changes of single tx submission to package, which is used to track addition/removal of transactions in the test. I'll continue working on re-adding these assertions for further invariant testing.
ACKs for top commit:
murchandamus:
ACK 262ab8ef7860d43cebc9d04721e3a075b4edf06e
glozow:
reACK 262ab8ef7860d43cebc9d04721e3a075b4edf06e
dergoegge:
tACK 262ab8ef7860d43cebc9d04721e3a075b4edf06e
Tree-SHA512: 190784777d0f2361b051b3271db8f79b7927e3cab88596d2c30e556da721510bd17f6cc96f6bb03403bbf0589ad3f799fa54e63c1b2bd92a2084485b5e3e96a5
b3db8c9d5ccfe5c31341169fa7ac044427122921 rpc: bumpfee, improve doc for 'reduce_output' arg (furszy)
Pull request description:
Fixes#28180. Resulted from discussions with S3RK, achow101, and Murch.
The current argument name and description are dangerous as it don't
describe the case where the user selects the recipient output as the
change address. This one could end up been increased by the inputs
minus outputs remainder. Which, when `bumpfee` adds new inputs
to the transaction, leads the process to send more coins to the
recipient. Which is not what the user would expect from a
'reduce_output' param naming.
ACKs for top commit:
S3RK:
ACK b3db8c9d5ccfe5c31341169fa7ac044427122921
achow101:
ACK b3db8c9d5ccfe5c31341169fa7ac044427122921
murchandamus:
ACK b3db8c9d5ccfe5c31341169fa7ac044427122921
Tree-SHA512: 91f607e2f5849041d7c099afdddae11af8bed5b1ac90c9d22921267f272e21b44e107d6968e037f05f958a61fe29e94e5fb44b224fb3606f197f83ec4ba3b1e7
Instead of storing the key material as an std::vector (with secure allocator),
use a secure_unique_ptr to a 32-byte array, and use nullptr for invalid keys.
This means a smaller CKey type, and no secure/dynamic memory usage for invalid
keys.
Bumpfee will try to increase the entire package to the target feerate,
which causes repeated bumpfees to quickly shoot up in fees, causing
intermittent failures when the fee is too large. We don't care about
this property, just that the child is continuously replaced until we
observe it's position in mapWallet is before its parent. Instead of
using bumpfee, we can create raw transactions which have only pay the
additional incremental relay fee, thus avoiding this problem.
See also https://github.com/bitcoin/bips/pull/1498
The benefit is a simpler implementation:
- The protocol state machine does not need separate states for garbage
authentication and version phases.
- The special case of "ignoring the ignore bit" is removed.
- The freedom to choose the contents of the garbage authentication
packet is removed. This simplifies testing.
Loading a wallet with conflicts without a chain (e.g. wallet tool and
migration) would previously result in an assertion due to -1 being both
a valid number of conflict confirmations, and the indicator that that
member has not been set yet.
MarkConflicted calculates conflict confirmations incorrectly when both
the last block processed height and the conflicting height are negative
(i.e. uninitialized). If either are negative, we should not be marking
conflicts and should exit early.
The current argument name and description are dangerous as it don't
describe the case where the user selects the recipient output as the
change address. This one could end up been increased by the inputs
minus outputs remainder. Which, when bumpfee adds new inputs
to the transaction, leads the process to send more coins to the
recipient. Which is not what the user would expect from a
'reduce_output' param naming.
Co-authored-by: Murch <murch@murch.one>
fa56c421be04af846f479c30749b17e6663ab418 Return CAutoFile from BlockManager::Open*File() (MarcoFalke)
9999b89cd37fb2a23c5ebcd91d9cb31d69375933 Make BufferedFile to be a CAutoFile wrapper (MarcoFalke)
fa389d902fbf5fac19fba8c5d0c5e0a25f15ca63 refactor: Drop unused fclose() from BufferedFile (MarcoFalke)
Pull request description:
This is required for https://github.com/bitcoin/bitcoin/pull/28052, but makes sense on its own, because offloading logic to `CAutoFile` instead of re-implementing it allows to delete code and complexity.
ACKs for top commit:
TheCharlatan:
Re-ACK fa56c421be04af846f479c30749b17e6663ab418
willcl-ark:
tACK fa56c421be
Tree-SHA512: fe4638f3a6bd3f9d968cfb9ae3259c9d6cd278fe2912cbc90289851311c8c781099db4c160e775960975c4739098d9af801a8d2d12603f371f8edfe134d8f85a
12f7257b8f6ba0de1fb05b598e916c8b14bcab8c doc: Be vague instead of wrong about MALLOC_ARENA_MAX (Tim Ruffing)
Pull request description:
Before this commit, we claim that glibc's malloc implementation uses 2 arenas by default. But that's true only on 32-bit systems, and even there, it uses *up* to 2 arenas.
This commit fixes the wrong statement. The new statement is intentionally vague to reduce our maintenance burden.
For details, see:
https://www.gnu.org/software/libc/manual/html_node/Memory-Allocation-Tunables.html#index-glibc_002emalloc_002earena_005fmax
Noticed in:
https://github.com/bitcoin/bitcoin/pull/27642#issuecomment-1728103427
ACKs for top commit:
fanquake:
ACK 12f7257b8f6ba0de1fb05b598e916c8b14bcab8c
Tree-SHA512: c0ff1e35b682a841e366a1cad26e18ff79a93d97103529be35a972c7dcbb95f5354e7a7b98a86731f491434d64685bb58cc3cc9100f0577d8f75db05e951b09a
4313c77400eb8eaa8586db39a7e29a861772ea80 make DisconnectedBlockTransactions responsible for its own memory management (glozow)
cf5f1faa037e9a40a5029cc7dd4ee61454b62466 MOVEONLY: DisconnectedBlockTransactions to its own file (glozow)
2765d6f3434c101fe2d46e9313e540aa680fbd77 rewrite DisconnectedBlockTransactions as a list + map (glozow)
79ce9f0aa46de8ff742be83fd6f68eab40e073ec add std::list to memusage (glozow)
59a35a7398f5bcb3e3805d1e4f363e4c2fb336b3 [bench] DisconnectedBlockTransactions (glozow)
925bb723ca71aa76380b769d8926c7c2ad9bbb7b [refactor] batch-add transactions to DisconnectedBlockTransactions (glozow)
Pull request description:
Motivation
- I think it's preferable to use stdlib data structures instead of depending on boost if we can achieve the same thing.
- Also see #28335 for further context/motivation. This PR simplifies that one.
Things done in this PR:
- Add a bench for `DisconnectedBlockTransactions` where we reorg and the new chain has {100%, 90%, 10%} of the same transactions. AFAIU in practice, it's usually close to 100%.
- Rewrite `DisconnectedBlockTransactions` as a `std::list` + `unordered_map` instead of a boost multi index container.
- On my machine, the bench suggests the performance is very similar.
- Move `DisconnectedBlockTransactions` from txmempool.h to its own kernel/disconnected_transactions.h. This struct isn't used by txmempool and doesn't have much to do with txmempool. My guess is that it's been living there for convenience since the boost includes are there.
ACKs for top commit:
ismaelsadeeq:
Tested ACK 4313c77400eb8eaa8586db39a7e29a861772ea80
stickies-v:
ACK 4313c77400eb8eaa8586db39a7e29a861772ea80
TheCharlatan:
ACK 4313c77400eb8eaa8586db39a7e29a861772ea80
Tree-SHA512: 273c80866bf3acd39b2a039dc082b7719d2d82e0940e1eb6c402f1c0992e997256722b85c7e310c9811238a770cfbdeb122ea4babbc23835d17128f214a1ef9e
a99e9e655a58b2364a74aec5cafb827a73c6b0c4 doc: add release note (ismaelsadeeq)
2b4edf889a4b555c8c7f6793fa5d820e5513ecac test: check `descriptorprocesspsbt` return hex encoded tx (ismaelsadeeq)
c405207a18fdee75a4dea470bb0d13e59e15ce45 rpc: `descriptorprocesspsbt` return hex encoded tx (ismaelsadeeq)
Pull request description:
Coming from [#28414 comment](https://github.com/bitcoin/bitcoin/pull/28414#pullrequestreview-1618684391) Same thing also for `descriptorprocesspsbt`.
Before this PR `descriptorprocesspsbt` returns a boolean `complete` which indicates that the psbt is final, users then have to call `finalizepsbt` to get the hex encoded network transaction.
In this PR if the psbt is complete the return object also has the hex encoded network transaction ready for broadcast with `sendrawtransaction`.
This save users calling `finalizepsbt` with the descriptor, if it is already complete.
ACKs for top commit:
achow101:
ACK a99e9e655a58b2364a74aec5cafb827a73c6b0c4
pinheadmz:
ACK a99e9e655a58b2364a74aec5cafb827a73c6b0c4
ishaanam:
ACK a99e9e655a58b2364a74aec5cafb827a73c6b0c4
Tree-SHA512: c3f1b1391d4df05216c463127cd593f8703840430a99febb54890bc66fadabf9d9530860605f347ec54c1694019173247a0e7a9eb879d3cbb420f9e8d9839b75
099dbe4224e0e896604e7f6901d0fc302b0bd3a0 GUI: TransactionRecord: When time/index/etc match, sort send before receive (Luke Dashjr)
2d182f77cd8100395cf47a721bd01dc8620c9718 Bugfix: Ignore ischange flag when we're not the sender (Luke Dashjr)
71fbdb7f403e673877be94a79cd4c6b13b0bbcd6 GUI: Remove SendToSelf TransactionRecord type (Luke Dashjr)
f3fbe99fcf90daec79d49fd5d868102dc99feb23 GUI: TransactionRecord: Refactor to turn send-to-self into send+receive pairs (Luke Dashjr)
b9765ba1d67d7b74c17f9ce70cad5487715208a0 GUI: TransactionRecord: Use "any from me" as the criteria for deciding whether a transaction is a send or receive (Luke Dashjr)
Pull request description:
Makes the GUI transaction list more like the RPC, and IMO clearer in general.
As a side effect, this also fixes the GUI entries when a transaction is a net profit to us, but some inputs were also from us.
Originally https://github.com/bitcoin/bitcoin/pull/15115
Has Concept ACKs from @*Empact @*jonasschnelli
ACKs for top commit:
hebasto:
ACK 099dbe4224e0e896604e7f6901d0fc302b0bd3a0.
Tree-SHA512: 7d581add2f59431aa019126d54232a1f15723def5147d7a1b672e9b6d525b6e5a944cc437701aa1bd5bd0fbe557a3d1f4b239337f42bdba4fe1d3960442d0e3b
9ea31eba04ff8dcb9d7d993ce28bb10731a35177 gui: Disable and uncheck blank when private keys are disabled (Andrew Chow)
Pull request description:
Unify the GUI's create wallet with the RPC createwallet so that the blank flag is not set when private keys are disabled.
ACKs for top commit:
S3RK:
Code review ACK 9ea31eba04ff8dcb9d7d993ce28bb10731a35177
jarolrod:
ACK 9ea31eba04ff8dcb9d7d993ce28bb10731a35177
pablomartin4btc:
tACK 9ea31eba04ff8dcb9d7d993ce28bb10731a35177
Tree-SHA512: 0c90dbd77e66f088c6a57711a4b91e254814c4ee301ab703807f281cacd4b08712d2dfeac7661f28bc0e93acc55d486a17b8b4a53ffa57093d992e7a3c51f4e8
eb8f58f5e4a249d55338304099e8238896d2316d Add functional test to catch too large vsize packages (Greg Sanders)
1a579f9d01256b0b2570168496d129a8b2009b35 Handle over-sized (in virtual bytes) packages with no in-mempool ancestors (Greg Sanders)
bc013fe8e3d0bae2ab766a8248219aa3c9e344df Bugfix: Pass correct virtual size to CheckPackageLimits (Luke Dashjr)
533660c58ad5a218671a9bc1537299b1d67bb55d Replace MAX_PACKAGE_SIZE with MAX_PACKAGE_WEIGHT to avoid vbyte confusion (Greg Sanders)
Pull request description:
(Alternative) Minimal subset of https://github.com/bitcoin/bitcoin/pull/28345 to:
1) Replace MAX_PACKAGE_SIZE with MAX_PACKAGE_WEIGHT which accounts for additional WU necessary to not exclude default chain limit transactions that would have been accepted individually. Avoids sigops vbyte confusion.
2) pass correct vsize to chain limit evaluations in package context
3) stop overly-large packages that have no existing mempool ancestors (also a bugfix by itself if someone sets non-standard chain limits)
This should fix the known issues while not blocking additional refactoring later.
ACKs for top commit:
achow101:
ACK eb8f58f5e4a249d55338304099e8238896d2316d
ariard:
Re-Code ACK eb8f58f5e
glozow:
reACK eb8f58f5e4a249d55338304099e8238896d2316d
Tree-SHA512: 1b5cca1a526207e25d387fcc29a776a3198c3a013dc2b35c6275b9d5a64db2476c154ebf52e3a1aed0b9924c75613f21a946577aa760de28cadf0c9c7f68dc39
d05be124dbc0b24fb69d0c28ba2d6b297d243751 test: added coverage to estimatefee (kevkevin)
Pull request description:
Added a assert for an rpc error when we try to estimate fee for the max conf_target
Line I am adding coverage to https://github.com/bitcoin/bitcoin/blob/master/src/rpc/fees.cpp#LL71C52-L71C52
ACKs for top commit:
MarcoFalke:
lgtm ACK d05be124dbc0b24fb69d0c28ba2d6b297d243751
Tree-SHA512: dfab075989446e33d1a5ff1a308f1ba1b9f80cce3848fbe4231f69212ceef456a3f2b19365a42123e0397c31893fd9f1fd9973cc00cfbb324386e12ed0e6bccc
f52cb02f700b58bca921a7aa24bfeee04760262b doc: make it clear that `node` in `addnode` refers to the node's address (brunoerg)
effd1efefb53c58f0e43fec4f019a19f97795553 test: `addnode` with an invalid command should throw an error (brunoerg)
56b27b84877376ffc32b3bad09f1047b23de4ba1 rpc, refactor: clean-up `addnode` (brunoerg)
Pull request description:
This PR:
- Adds test coverage for an invalid `command` in `addnode`.
- Rename `test_getaddednodeinfo` to `test_addnode_getaddednodeinfo` and its log since this function also tests `addnode` and it doesn't worth to split into 2 ones.
- Makes it clear in docs that `node` in `addnode` refers to the node's address. It seemed a little weird for me "The node (see getpeerinfo for nodes)", it could mean a lot of things e.g. the node id.
- Some small improv/clean-up: use `const` where possible, rename some vars, and remove the check for nullance for `command` since it's a non-optional field.
ACKs for top commit:
achow101:
ACK f52cb02f700b58bca921a7aa24bfeee04760262b
jonatack:
ACK f52cb02f700b58bca921a7aa24bfeee04760262b
theStack:
re-ACK f52cb02f700b58bca921a7aa24bfeee04760262b
Tree-SHA512: e4a69e58b784e233463945b4d55a401957f9fe4562c129f59216a44f44fb3221d3449ac578fb35e665ca654c6ade2e741b72c3df78040f7527229c77b6c5b82e
83d7cfd5429b0be7755bc48145032956f5f56dae test: refactor: deduplicate segwitv0 ECDSA signing for tx inputs (Sebastian Falbesoner)
Pull request description:
This PR is a simple follow-up for #28025. It introduces a `signing_input_segwitv0` helper in order to deduplicate the following steps needed to create a segwitv0 ECDSA signature:
1. calculate the `SegwitV0SignatureHash` with the desired sighash type
2. create the actual digital signature by calling ECKey.sign_ecdsa on the signature message hash calculated above
3. put the DER-encoded result (plus sighash byte) at the bottom of the witness stack
ACKs for top commit:
achow101:
ACK 83d7cfd5429b0be7755bc48145032956f5f56dae
pinheadmz:
code review ACK at 83d7cfd5429b0be7755bc48145032956f5f56dae
Tree-SHA512: b8e55409ddc9ddb14cfc06daeb4730d7750a4632f175f88dcac6ec4d216e71fd4a7eee325a64d6ebba3b33be50bcd30c2de7400f834c01abb67e52840d9823b6
fa3b5e5e57cd4649d577e06a3aca798b55a75fd5 ci: Use nproc over MAKEJOBS in 01_base_install (MarcoFalke)
Pull request description:
Currently `$MAKEJOBS` is the default value in `01_base_install.sh` when building the container image.
This problem can't be fixed (see below), so just use `nproc` for now.
Other solutions would be bad:
* Passing in the `MAKEJOBS` as a dockerfile env would create a new image if the number of tasks are changed, seems verbose and confusing.
* Leaving `master` as-is would leave CPUs unused if there are more than `4`.
ACKs for top commit:
fanquake:
ACK - I think this is fine as-is, it's an improvement over the current state fa3b5e5e57cd4649d577e06a3aca798b55a75fd5
Tree-SHA512: 15014eb7b548945737b0fed5cd46f0cd4b72b1d54d044f60fce628f914053a2de6518878428a54822d236d08d6f257d8c464d3fb589400f4be56022d2ec8676d
