https://github.com/jimingham updated https://github.com/llvm/llvm-project/pull/138216
>From 656fe559f84526fd3edc91b1c0d12fd56d838085 Mon Sep 17 00:00:00 2001 From: Jim Ingham <jing...@apple.com> Date: Thu, 1 May 2025 16:27:37 -0700 Subject: [PATCH 1/2] Don't hold the Target's ModuleListLock over running LoadScriptingResourceInTarget. That calls an unknown amount of Python code, and can do quite a bit of work - especially if people do things like launch scripted processes in this script affordance. Doing that while holding a major lock like the ModuleList lock is asking for trouble. I tried to make a test that would actually stall without this, but I couldn't come up with anything that reliably failed. You always have to get pretty unlucky. --- lldb/source/Core/ModuleList.cpp | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/lldb/source/Core/ModuleList.cpp b/lldb/source/Core/ModuleList.cpp index 6052cc151744d..9724039decf0d 100644 --- a/lldb/source/Core/ModuleList.cpp +++ b/lldb/source/Core/ModuleList.cpp @@ -1046,8 +1046,14 @@ bool ModuleList::LoadScriptingResourcesInTarget(Target *target, bool continue_on_error) { if (!target) return false; - std::lock_guard<std::recursive_mutex> guard(m_modules_mutex); - for (auto module : m_modules) { + m_modules_mutex.lock(); + // Don't hold the module list mutex while loading the scripting resources, + // The initializer might do any amount of work, and having that happen while + // the module list is held is asking for A/B locking problems. + const ModuleList tmp_module_list(*this); + m_modules_mutex.unlock(); + + for (auto module : tmp_module_list.ModulesNoLocking()) { if (module) { Status error; if (!module->LoadScriptingResourceInTarget(target, error, >From 21b3c847236c239e07cbf14220ea6516181e3d13 Mon Sep 17 00:00:00 2001 From: Jim Ingham <jing...@apple.com> Date: Fri, 2 May 2025 11:50:57 -0700 Subject: [PATCH 2/2] formatting --- lldb/source/Core/ModuleList.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lldb/source/Core/ModuleList.cpp b/lldb/source/Core/ModuleList.cpp index 9724039decf0d..d5ddf6e846112 100644 --- a/lldb/source/Core/ModuleList.cpp +++ b/lldb/source/Core/ModuleList.cpp @@ -1052,7 +1052,7 @@ bool ModuleList::LoadScriptingResourcesInTarget(Target *target, // the module list is held is asking for A/B locking problems. const ModuleList tmp_module_list(*this); m_modules_mutex.unlock(); - + for (auto module : tmp_module_list.ModulesNoLocking()) { if (module) { Status error; _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits