Fix issue where if a client disconnects in the middle of a long running IPC method call, the server will segfault when the method eventually returns.
This issue was reported tdb3 in https://github.com/bitcoin/bitcoin/pull/31003#pullrequestreview-2349619672 with a stack trace showing where the crash happens in the PassField mp.Context overload while calling request_threads.erase.
Fix issue where if a client disconnects in the middle of a long running IPC
method call, the server will segfault when the method eventually returns.
This behavior was reported by tdb3 in
https://github.com/bitcoin/bitcoin/pull/31003#pullrequestreview-2349619672
including a stack trace showing where the crash happens in the PassField
mp.Context overload while calling request_threads.erase.
Originally posted by @tdb3 in https://github.com/bitcoin/bitcoin/pull/31003#pullrequestreview-2349619672:
I did, however, run into a repeatable segfault that appears to be occurring with bitcoin_node when running bitcoin-mine (which calls
waitFeesChanged()), interrupting bitcoin-mine (CTRL-C while it waits for change), then generating a block (withbitcoin-cli). Feels a bit DoSsy. Could be something I'm overlooking/messed up on my end. Not sure. Please request more details if needed. bitcoin-node gdb trace2024-10-06T17:11:13Z [ipc] {bitcoin-node-67256/b-capnp-loop-67260} IPC server post request [#4](/bitcoin-core-multiprocess/4/) {bitcoin-node-67256/b-capnp-loop-67291 (from bitcoin-mine-67289/bitcoin-mine-67289)} Thread 3 "b-capnp-loop" received signal SIGPIPE, Broken pipe. [Switching to Thread 0x7ffff6dfe6c0 (LWP 67260)] __GI___writev (iovcnt=2, iov=0x7ffff6dfc6c0, fd=31) at ../sysdeps/unix/sysv/linux/writev.c:26 26 ../sysdeps/unix/sysv/linux/writev.c: No such file or directory. (gdb) c Continuing. 2024-10-06T17:11:23Z [ipc] {bitcoin-node-67256/b-capnp-loop-67260} IPC server: socket disconnected. 2024-10-06T17:11:23Z [ipc] {bitcoin-node-67256/b-capnp-loop-67260} IPC server destroy N2mp11ProxyServerIN3ipc5capnp8messages4InitEEE 2024-10-06T17:11:26Z CreateNewBlock(): block weight: 888 txs: 0 fees: 0 sigops 400 2024-10-06T17:11:26Z Saw new header hash=7227516712ea6f9f8fb24763a3ba8eeb3ecee4d0640f1227a41320b66cf6605a height=111 2024-10-06T17:11:26Z UpdateTip: new best=7227516712ea6f9f8fb24763a3ba8eeb3ecee4d0640f1227a41320b66cf6605a height=111 version=0x20000000 log2_work=7.807355 tx=118 date='2024-10-06T17:11:26Z' progress=1.000000 cache=0.3MiB(8txo) 2024-10-06T17:11:26Z [test] AddToWallet 20a7fcb543900a59764414197f5aaf36e85454dc916c4049c4fe4f0eb31381e4 new Confirmed (block=7227516712ea6f9f8fb24763a3ba8eeb3ecee4d0640f1227a41320b66cf6605a, height=111, index=0) Thread 30 "b-capnp-loop" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fff9d7fa6c0 (LWP 67291)] 0x00007ffff7cc0193 in std::_Rb_tree_rebalance_for_erase(std::_Rb_tree_node_base*, std::_Rb_tree_node_base&) () from /lib/x86_64-linux-gnu/libstdc++.so.6 (gdb) bt [#0](/bitcoin-core-multiprocess/0/) 0x00007ffff7cc0193 in std::_Rb_tree_rebalance_for_erase(std::_Rb_tree_node_base*, std::_Rb_tree_node_base&) () from /lib/x86_64-linux-gnu/libstdc++.so.6 [#1](/bitcoin-core-multiprocess/1/) 0x0000555555a889d9 in std::_Rb_tree<mp::Connection*, std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> >, std::_Select1st<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > >, std::less<mp::Connection*>, std::allocator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > > >::_M_erase_aux (__position=..., this=<optimized out>) at /usr/include/c++/12/bits/stl_tree.h:2488 [#2](/bitcoin-core-multiprocess/2/) std::_Rb_tree<mp::Connection*, std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> >, std::_Select1st<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > >, std::less<mp::Connection*>, std::allocator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > > >::erase[abi:cxx11](std::_Rb_tree_iterator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > >) (__position=..., this=<optimized out>) at /usr/include/c++/12/bits/stl_tree.h:1209 [#3](/bitcoin-core-multiprocess/3/) std::map<mp::Connection*, mp::ProxyClient<mp::Thread>, std::less<mp::Connection*>, std::allocator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > > >::erase[abi:cxx11](std::_Rb_tree_iterator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > >) (__position=..., this=<optimized out>) at /usr/include/c++/12/bits/stl_map.h:1086 [#4](/bitcoin-core-multiprocess/4/) mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#2}::operator()() const (__closure=<synthetic pointer>) at ../../../depends/x86_64-pc-linux-gnu/include/mp/proxy-types.h:156 [#5](/bitcoin-core-multiprocess/5/) mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#2}::operator()() const (__closure=<synthetic pointer>) at ../../../depends/x86_64-pc-linux-gnu/include/mp/proxy-types.h:156 [#6](/bitcoin-core-multiprocess/6/) kj::_::Deferred<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#2}>::run() (this=0x7fff9d7f9250) at ../../../depends/x86_64-pc-linux-gnu/include/kj/common.h:2001 [#7](/bitcoin-core-multiprocess/7/) kj::_::Deferred<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fi--Type <RET> for more, q to quit, c to continue without paging-- elds::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#2}>::~Deferred() (this=0x7fff9d7f9250, __in_chrg=<optimized out>) at ../../../depends/x86_64-pc-linux-gnu/include/kj/common.h:1990 [#8](/bitcoin-core-multiprocess/8/) mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()() (__closure=0x7fffe801b640) at ../../../depends/x86_64-pc-linux-gnu/include/mp/proxy-types.h:161 [#9](/bitcoin-core-multiprocess/9/) 0x0000555555d5145f in mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::{lambda()#1}::operator()() const () [#10](/bitcoin-core-multiprocess/10/) 0x00007ffff7cd44a3 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6 [#11](/bitcoin-core-multiprocess/11/) 0x00007ffff7aa8144 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442 [#12](/bitcoin-core-multiprocess/12/) 0x00007ffff7b287dc in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81 (gdb)
Still encountering a segfault. Trace below.
2024-10-08T21:37:33Z [ipc] {bitcoin-node-72507/b-capnp-loop-72511} IPC server: socket disconnected.
2024-10-08T21:37:33Z [ipc] {bitcoin-node-72507/b-capnp-loop-72511} IPC server destroy N2mp11ProxyServerIN3ipc5capnp8messages4InitEEE
2024-10-08T21:37:38Z CreateNewBlock(): block weight: 888 txs: 0 fees: 0 sigops 400
2024-10-08T21:37:38Z Saw new header hash=08c6cb824e73a5ff8db130c814ff064a4cb13a04179041159b70b71c7ae8e9cd height=111
2024-10-08T21:37:38Z UpdateTip: new best=08c6cb824e73a5ff8db130c814ff064a4cb13a04179041159b70b71c7ae8e9cd height=111 version=0x20000000 log2_work=7.807355 tx=118 date='2024-10-08T21:37:38Z' progress=1.000000 cache=0.3MiB(8txo)
2024-10-08T21:37:38Z [test] AddToWallet b953fe9cf081f57db02556a1fa9b0e0d5a626f2ce1202585c9ae23859f39481f new Confirmed (block=08c6cb824e73a5ff8db130c814ff064a4cb13a04179041159b70b71c7ae8e9cd, height=111, index=0)
Thread 30 "b-capnp-loop" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fff9d7fa6c0 (LWP 72541)]
0x00007ffff7cc0193 in std::_Rb_tree_rebalance_for_erase(std::_Rb_tree_node_base*, std::_Rb_tree_node_base&) () from /lib/x86_64-linux-gnu/libstdc++.so.6
(gdb) bt
[#0](/bitcoin-core-multiprocess/0/) 0x00007ffff7cc0193 in std::_Rb_tree_rebalance_for_erase(std::_Rb_tree_node_base*, std::_Rb_tree_node_base&) () from /lib/x86_64-linux-gnu/libstdc++.so.6
[#1](/bitcoin-core-multiprocess/1/) 0x0000555555a889d9 in std::_Rb_tree<mp::Connection*, std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> >, std::_Select1st<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > >, std::less<mp::Connection*>, std::allocator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > > >::_M_erase_aux (__position=..., this=<optimized out>) at /usr/include/c++/12/bits/stl_tree.h:2488
[#2](/bitcoin-core-multiprocess/2/) std::_Rb_tree<mp::Connection*, std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> >, std::_Select1st<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > >, std::less<mp::Connection*>, std::allocator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > > >::erase[abi:cxx11](std::_Rb_tree_iterator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > >) (__position=..., this=<optimized out>)
at /usr/include/c++/12/bits/stl_tree.h:1209
[#3](/bitcoin-core-multiprocess/3/) std::map<mp::Connection*, mp::ProxyClient<mp::Thread>, std::less<mp::Connection*>, std::allocator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > > >::erase[abi:cxx11](std::_Rb_tree_iterator<std::pair<mp::Connection* const, mp::ProxyClient<mp::Thread> > >) (__position=...,
this=<optimized out>) at /usr/include/c++/12/bits/stl_map.h:1086
[#4](/bitcoin-core-multiprocess/4/) mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#2}::operator()() const (__closure=<synthetic pointer>)
at ../../../depends/x86_64-pc-linux-gnu/include/mp/proxy-types.h:156
[#5](/bitcoin-core-multiprocess/5/) mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#2}::operator()() const (__closure=<synthetic pointer>)
at ../../../depends/x86_64-pc-linux-gnu/include/mp/proxy-types.h:156
[#6](/bitcoin-core-multiprocess/6/) kj::_::Deferred<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#2}>::run() (this=0x7fff9d7f9250)
at ../../../depends/x86_64-pc-linux-gnu/include/kj/common.h:2001
[#7](/bitcoin-core-multiprocess/7/) kj::_::Deferred<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#2}>::~Deferred() (this=0x7fff9d7f9250, __in_chrg=<optimized out>)
at ../../../depends/x86_64-pc-linux-gnu/include/kj/common.h:1990
--Type <RET> for more, q to quit, c to continue without paging--
[#8](/bitcoin-core-multiprocess/8/) mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()() (__closure=0x7fffe8017e40) at ../../../depends/x86_64-pc-linux-gnu/include/mp/proxy-types.h:161
[#9](/bitcoin-core-multiprocess/9/) 0x0000555555d5145f in mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::{lambda()#1}::operator()() const ()
[#10](/bitcoin-core-multiprocess/10/) 0x00007ffff7cd44a3 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
[#11](/bitcoin-core-multiprocess/11/) 0x00007ffff7aa8144 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
[#12](/bitcoin-core-multiprocess/12/) 0x00007ffff7b287dc in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81
(gdb)
Following the instructions from https://github.com/bitcoin/bitcoin/pull/31003#pullrequestreview-2349619672 (complicated but steps to reproduce were described very clearly!) I was able to reproduce the original segfault and a new segfault after applying the current fix 7f1d33f81c48585cba6ea6c20afc1cd64bea2772
Will debug, but stack trace is:
[#0](/bitcoin-core-multiprocess/0/) std::operator== (__x=..., __y=...) at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/std_thread.h:330
[#1](/bitcoin-core-multiprocess/1/) mp::EventLoop::post(std::function<void ()> const&) (this=0x0, fn=...) at /home/russ/work/mp/src/mp/proxy.cpp:219
[#2](/bitcoin-core-multiprocess/2/) 0x000055ac4fc57dc4 in mp::EventLoop::sync<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#3}::operator()() const::{lambda()#1}>(mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#3}::operator()() const::{lambda()#1}&&) (this=0x0, callable=...) at /home/russ/work/mp/build/prefix/include/mp/proxy-io.h:155
[#3](/bitcoin-core-multiprocess/3/) 0x000055ac4fc57d44 in mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#3}::operator()() const (this=0x7f1c4affc7e8) at /home/russ/work/mp/build/prefix/include/mp/proxy-types.h:171
[#4](/bitcoin-core-multiprocess/4/) 0x000055ac4fc52267 in kj::runCatchingExceptions<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#3}>(mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()()::{lambda()#3}&&) (func=...) at /nix/store/0rvzw1dahhd1h8qyhyxmwgr2l745fn3a-capnproto-1.0.2/include/kj/exception.h:371
[#5](/bitcoin-core-multiprocess/5/) 0x000055ac4fc51db9 in mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}::operator()() (this=0x7f1c8001c4d0) at /home/russ/work/mp/build/prefix/include/mp/proxy-types.h:171
[#6](/bitcoin-core-multiprocess/6/) 0x000055ac4fc51afe in mp::AsyncCallable<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}>::operator()() const (this=0x7f1c8001c440) at /home/russ/work/mp/build/prefix/include/mp/util.h:189
[#7](/bitcoin-core-multiprocess/7/) 0x000055ac4fc51aa6 in std::__invoke_impl<void, mp::AsyncCallable<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}>&>(std::__invoke_other, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&&) (__f=...) at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/invoke.h:61
[#8](/bitcoin-core-multiprocess/8/) 0x000055ac4fc519f6 in std::__invoke_r<void, mp::AsyncCallable<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}>&>(mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&&) (__fn=...) at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/invoke.h:111
[#9](/bitcoin-core-multiprocess/9/) 0x000055ac4fc5182e in std::_Function_handler<void (), mp::AsyncCallable<mp::PassField<mp::Accessor<mp::mining_fields::Context, 17>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > >, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > > >(mp::Priority<1>, mp::TypeList<>, mp::ServerInvokeContext<mp::ProxyServer<ipc::capnp::messages::Mining>, capnp::CallContext<ipc::capnp::messages::Mining::WaitFeesChangedParams, ipc::capnp::messages::Mining::WaitFeesChangedResults> >&, mp::ServerField<1, mp::Accessor<mp::mining_fields::CurrentTip, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::FeeThreshold, 1>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Options, 17>, mp::ServerField<1, mp::Accessor<mp::mining_fields::Timeout, 1>, mp::ServerRet<mp::Accessor<mp::mining_fields::Result, 2>, mp::ServerCall> > > > > const&, mp::TypeList<uint256, long, node::BlockCreateOptions const&, std::chrono::duration<double, std::ratio<1l, 1000l> > >&&)::{lambda()#1}> >::_M_invoke(std::_Any_data const&) (__functor=...)
at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/std_function.h:290
[#10](/bitcoin-core-multiprocess/10/) 0x000055ac5016f360 in std::function<void ()>::operator()() const (this=<optimized out>) at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/std_function.h:591
[#11](/bitcoin-core-multiprocess/11/) mp::Waiter::wait<mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const::{lambda()#1}>(std::unique_lock<std::mutex>&, mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const::{lambda()#1})::{lambda()#1}::operator()() const (this=<optimized out>) at /home/russ/work/mp/include/mp/proxy-io.h:261
[#12](/bitcoin-core-multiprocess/12/) std::condition_variable::wait<mp::Waiter::wait<mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const::{lambda()#1}>(std::unique_lock<std::mutex>&, mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const::{lambda()#1})::{lambda()#1}>(std::unique_lock<std::mutex>&, mp::Waiter::wait<mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const::{lambda()#1}>(std::unique_lock<std::mutex>&, mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const::{lambda()#1})::{lambda()#1}) (this=0x7f1c44001278, __lock=..., __p=...) at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/condition_variable:104
[#13](/bitcoin-core-multiprocess/13/) mp::Waiter::wait<mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const::{lambda()#1}>(std::unique_lock<std::mutex>&, mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const::{lambda()#1}) (this=0x7f1c44001250, lock=..., pred=...) at /home/russ/work/mp/include/mp/proxy-io.h:251
[#14](/bitcoin-core-multiprocess/14/) mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0::operator()() const (this=<optimized out>) at /home/russ/work/mp/src/mp/proxy.cpp:364
[#15](/bitcoin-core-multiprocess/15/) std::__invoke_impl<void, mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0>(std::__invoke_other, mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0&&) (__f=...) at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/invoke.h:61
[#16](/bitcoin-core-multiprocess/16/) std::__invoke<mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0>(mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0&&) (__fn=...) at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/invoke.h:96
[#17](/bitcoin-core-multiprocess/17/) std::thread::_Invoker<std::tuple<mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) (this=<optimized out>)
at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/std_thread.h:292
[#18](/bitcoin-core-multiprocess/18/) std::thread::_Invoker<std::tuple<mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0> >::operator()() (this=<optimized out>)
at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/std_thread.h:299
[#19](/bitcoin-core-multiprocess/19/) std::thread::_State_impl<std::thread::_Invoker<std::tuple<mp::ProxyServer<mp::ThreadMap>::makeThread(capnp::CallContext<mp::ThreadMap::MakeThreadParams, mp::ThreadMap::MakeThreadResults>)::$_0> > >::_M_run() (this=<optimized out>)
at /nix/store/rqga421d43q40blrrgmiw820p01a4nba-gcc-13.2.0/include/c++/13.2.0/bits/std_thread.h:244
[#20](/bitcoin-core-multiprocess/20/) 0x00007f1c90ee8683 in execute_native_thread_routine () from /nix/store/agp6lqznayysqvqkx4k1ggr8n1rsyi8c-gcc-13.2.0-lib/lib/libstdc++.so.6
[#21](/bitcoin-core-multiprocess/21/) 0x00007f1c90bc0383 in start_thread () from /nix/store/1rm6sr6ixxzipv5358x0cmaw8rs84g2j-glibc-2.38-44/lib/libc.so.6
[#22](/bitcoin-core-multiprocess/22/) 0x00007f1c90c4300c in clone3 () from /nix/store/1rm6sr6ixxzipv5358x0cmaw8rs84g2j-glibc-2.38-44/lib/libc.so.6
This an imperfect workaround for a crash that can be triggered if a client
disconnects in the middle of a long running IPC call. The workaround results in
memory leak but avoids a crash. This can be improved later, and more details
are in a code comment.
The second crash turned out to be more complicated to fix than the first one, so just pushing a workaround for now that avoids the crash but results in a small memory leak. I will open a separate PR with a more complete fix. I should also add a test for this issue making sure deleting server-side Connection* during an ongoing method call does not cause crashes.
The second crash turned out to be more complicated to fix than the first one, so just pushing a workaround for now that avoids the crash but results in a small memory leak. I will open a separate PR with a more complete fix.
Note: this is done now. The second commit of this PR was reverted in #186. The workaround was no longer needed after #160, and it was actually causing intermittent test hangs in the new unit test added in #160 disconnecting the client during an IPC call.