Bug 445743 - "The impossible happened: mutex is locked simultaneously by two threads...

Been using the same fix in FreeBSD for quite a while, so I think
it's safe to apply to Linux and close the bugzi item.

diff --git a/NEWS b/NEWS
index c6ebdcb2523c406e946b9ad035669f127c713120..e31fc3c50d4e2e04ce512e1ec28485693833fcef 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -87,6 +87,8 @@ are not entered into bugzilla tend to get forgotten about or ignored.
 444110  priv/guest_ppc_toIR.c:36198:31: warning: duplicated 'if' condition.
 444488  Use glibc.pthread.stack_cache_size tunable
 444568  drd/tests/pth_barrier_thr_cr fails on Fedora 38
+445743  "The impossible happened: mutex is locked simultaneously by two threads"
+        while using mutexes with priority inheritance and signals
 459476  vgdb: allow address reuse to avoid "address already in use" errorsuse" errors
 460356  s390: Sqrt32Fx4 -- cannot reduce tree
 462830  WARNING: unhandled amd64-freebsd syscall: 474
@@ -95,7 +97,7 @@ are not entered into bugzilla tend to get forgotten about or ignored.
 464859  Build failures with GCC-13 (drd tsan_unittest)
 464969  D language demangling
 465435  m_libcfile.c:66 (vgPlain_safe_fd): Assertion 'newfd >= VG_(fd_hard_limit)' failed.
-n-i-bz  FreeBSD rfork syscall fail with EINVAL or EINVAL rather than VG_(unimplemented)
+n-i-bz  FreeBSD rfork syscall fail with EINVAL or ENOSYS rather than VG_(unimplemented)
 
 To see details of a given bug, visit
   https://bugs.kde.org/show_bug.cgi?id=XXXXXX

diff --git a/coregrind/m_syswrap/syswrap-linux.c b/coregrind/m_syswrap/syswrap-linux.c
index bb87c90bab5e62b22662f9c58ab8ac31e1598112..4a5a93b35a2f5ed8a00c812f3783410a586489bc 100644 (file)
--- a/coregrind/m_syswrap/syswrap-linux.c
+++ b/coregrind/m_syswrap/syswrap-linux.c
@@ -1743,6 +1743,9 @@ static void futex_pre_helper ( ThreadId tid, SyscallArgLayout* layout,
    }
 
    *flags |= SfMayBlock;
+   if ((ARG2 & (VKI_FUTEX_PRIVATE_FLAG|VKI_FUTEX_LOCK_PI)) == (VKI_FUTEX_PRIVATE_FLAG|VKI_FUTEX_LOCK_PI)) {
+      *flags |= SfKernelRestart;
+   }
 
    switch(ARG2 & ~(VKI_FUTEX_PRIVATE_FLAG|VKI_FUTEX_CLOCK_REALTIME)) {
    case VKI_FUTEX_WAIT: