Segfault in qt/clientmodel.cpp:92 on every shutdown #800

1. 
   maflcko commented at 8:20 am on February 28, 2024: contributor

   Is there an existing issue for this?

   • I have searched the existing issues

   Current behaviour

   On shutdown, I get a crash in return m_node.getNodeCount(connections);

   Expected behaviour

   No crash

   Steps to reproduce

   • Shutdown Bitcoin Core

   Relevant log output

   No response

   How did you obtain Bitcoin Core

   Compiled from source

   What version of Bitcoin Core are you using?

   master

   Operating system and version

   ubuntu

   Machine specifications

   No response

2. 
   maflcko commented at 8:31 am on February 28, 2024: contributor

   The thread b-msghand is still busy in ActivateBestChainStep, the thread b-shutoff is currently joining the message handler thread in CConnman::StopThreads net.cpp:3336.

   The thread bitcoin-qt is the one segfaulting.

3. maflcko added this to the milestone 27.0 on Feb 28, 2024
4. 
   maflcko commented at 9:29 am on February 28, 2024: contributor

   Steps to reproduce:

    0diff --git a/src/qt/bitcoingui.cpp b/src/qt/bitcoingui.cpp
    1index ad80922c8b..d6ca01ebc4 100644
    2--- a/src/qt/bitcoingui.cpp
    3+++ b/src/qt/bitcoingui.cpp
    4@@ -989,6 +989,7 @@ void BitcoinGUI::gotoLoadPSBT(bool from_clipboard)
    5 
    6 void BitcoinGUI::updateNetworkState()
    7 {
    8+UninterruptibleSleep(100ms);
    9     int count = clientModel->getNumConnections();
   10     QString icon;
   11     switch(count)
   12diff --git a/src/validation.cpp b/src/validation.cpp
   13index 81a3c35864..c18608dcd7 100644
   14--- a/src/validation.cpp
   15+++ b/src/validation.cpp
   16@@ -3140,6 +3140,7 @@ bool Chainstate::ActivateBestChainStep(BlockValidationState& state, CBlockIndex*
   17 
   18         // Connect new blocks.
   19         for (CBlockIndex* pindexConnect : reverse_iterate(vpindexToConnect)) {
   20+        UninterruptibleSleep(3s);
   21             if (!ConnectTip(state, pindexConnect, pindexConnect == pindexMostWork ? pblock : std::shared_ptr<const CBlock>(), connectTrace, disconnectpool)) {
   22                 if (state.IsInvalid()) {
   23                     // The block violates a consensus rule.
   

   0gdb --args ./src/qt/bitcoin-qt -signet -datadir=/run/media/marco/scratch_fde/signet/ -printtoconsole  -server
   1...
   2run
   

   0while ./src/bitcoin-cli -signet -datadir=/run/media/marco/scratch_fde/signet/ setnetworkactive true && sleep 0.2 && ./src/bitcoin-cli -signet -datadir=/run/media/marco/scratch_fde/signet/ setnetworkactive false ; do true ; done
   

   • Exit the GUI via the [x] button
5. furszy cross-referenced this on Feb 28, 2024 from issue Fix nullptr clientModel access during shutdown by furszy
6. 
   furszy commented at 1:12 pm on February 28, 2024: member

   #801
7. 
   hebasto commented at 1:13 pm on February 28, 2024: member

   #801 @maflcko Does it fix the issue for you?

8. hebasto referenced this in commit 776d48dd56 on Mar 4, 2024
9. 
   hebasto commented at 10:17 am on March 4, 2024: member

   Closed by #801.
10. hebasto closed this on Mar 4, 2024

    ---

Contributors
maflcko furszy hebasto

Milestone
27.0