commit 798fd205928acfdd6b5baafe382830ec6f6998ce
author Kuba (Brecka) Mracek <mracek@apple.com> Fri Jul 07 14:42:19 2017 -0700
committer GitHub <noreply@github.com> Fri Jul 07 14:42:19 2017 -0700
tree 236ce8c205f1f70c2657894fde6977a549217227
parent 5f8d94ed64b4e8709a10acdae5fa060b0cdf88b4

TSan: Don't save stack in ThreadIgnoreBegin to avoid a deadlock when forking. (#10)

lib/tsan/rtl/tsan_interceptors.cc

diff --git a/lib/tsan/rtl/tsan_interceptors.cc b/lib/tsan/rtl/tsan_interceptors.cc
index 9bf1b28..88644a8 100644
--- a/lib/tsan/rtl/tsan_interceptors.cc
+++ b/lib/tsan/rtl/tsan_interceptors.cc
@@ -277,7 +277,7 @@
 
 void ScopedInterceptor::EnableIgnores() {
   if (ignoring_) {
-    ThreadIgnoreBegin(thr_, pc_);
+    ThreadIgnoreBegin(thr_, pc_, false);
     if (in_ignored_lib_) {
       DCHECK(!thr_->in_ignored_lib);
       thr_->in_ignored_lib = true;

lib/tsan/rtl/tsan_rtl.cc

diff --git a/lib/tsan/rtl/tsan_rtl.cc b/lib/tsan/rtl/tsan_rtl.cc
index bc5991c..bd98740 100644
--- a/lib/tsan/rtl/tsan_rtl.cc
+++ b/lib/tsan/rtl/tsan_rtl.cc
@@ -980,13 +980,13 @@
   thr->shadow_stack_pos--;
 }
 
-void ThreadIgnoreBegin(ThreadState *thr, uptr pc) {
+void ThreadIgnoreBegin(ThreadState *thr, uptr pc, bool save_stack) {
   DPrintf("#%d: ThreadIgnoreBegin\n", thr->tid);
   thr->ignore_reads_and_writes++;
   CHECK_GT(thr->ignore_reads_and_writes, 0);
   thr->fast_state.SetIgnoreBit();
 #if !SANITIZER_GO
-  if (!ctx->after_multithreaded_fork)
+  if (save_stack && !ctx->after_multithreaded_fork)
     thr->mop_ignore_set.Add(CurrentStackId(thr, pc));
 #endif
 }

lib/tsan/rtl/tsan_rtl.h

diff --git a/lib/tsan/rtl/tsan_rtl.h b/lib/tsan/rtl/tsan_rtl.h
index 8853941..81cefca 100644
--- a/lib/tsan/rtl/tsan_rtl.h
+++ b/lib/tsan/rtl/tsan_rtl.h
@@ -707,7 +707,7 @@
 void MemoryRangeFreed(ThreadState *thr, uptr pc, uptr addr, uptr size);
 void MemoryRangeImitateWrite(ThreadState *thr, uptr pc, uptr addr, uptr size);
 
-void ThreadIgnoreBegin(ThreadState *thr, uptr pc);
+void ThreadIgnoreBegin(ThreadState *thr, uptr pc, bool save_stack = true);
 void ThreadIgnoreEnd(ThreadState *thr, uptr pc);
 void ThreadIgnoreSyncBegin(ThreadState *thr, uptr pc);
 void ThreadIgnoreSyncEnd(ThreadState *thr, uptr pc);