Merge remote-tracking branch 'remotes/stsquad/tags/pull-testing-tcg-plugins-270520-1' into staging

Testing and one plugin fix:

  - support alternates for genisoimage to test/vm
  - add clang++ to clang tests
  - fix record/replay smoke test
  - enable more softfloat tests
  - better detection of hung gdb
  - upgrade aarch64 tcg test x-compile to gcc-10
  - fix plugin cpu_index clash vs threads

# gpg: Signature made Wed 27 May 2020 14:29:20 BST
# gpg:                using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [full]
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* remotes/stsquad/tags/pull-testing-tcg-plugins-270520-1:
  tests/tcg: add new threadcount test
  linux-user: properly "unrealize" vCPU object
  cpus-common: ensure auto-assigned cpu_indexes don't clash
  tests/docker: use a gcc-10 based image for arm64 tests
  tests/docker: add debian11 base image
  tests/tcg: better detect confused gdb which can't connect
  tests/fp: split and audit the conversion tests
  tests/fp: enable extf80_le_quite tests
  tests/tcg: fix invocation of the memory record/replay tests
  travis.yml: Use clang++ in the Clang tests
  tests/vm: pass --genisoimage to basevm script
  configure: add alternate binary for genisoimage

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 11 insertions, 8 deletions

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 05f03919ff..7f6700c54e 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -7635,30 +7635,33 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
             return -TARGET_ERESTARTSYS;
         }
 
-        cpu_list_lock();
+        pthread_mutex_lock(&clone_lock);
 
         if (CPU_NEXT(first_cpu)) {
-            TaskState *ts;
+            TaskState *ts = cpu->opaque;
 
-            /* Remove the CPU from the list.  */
-            QTAILQ_REMOVE_RCU(&cpus, cpu, node);
+            object_property_set_bool(OBJECT(cpu), false, "realized", NULL);
+            object_unref(OBJECT(cpu));
+            /*
+             * At this point the CPU should be unrealized and removed
+             * from cpu lists. We can clean-up the rest of the thread
+             * data without the lock held.
+             */
 
-            cpu_list_unlock();
+            pthread_mutex_unlock(&clone_lock);
 
-            ts = cpu->opaque;
             if (ts->child_tidptr) {
                 put_user_u32(0, ts->child_tidptr);
                 do_sys_futex(g2h(ts->child_tidptr), FUTEX_WAKE, INT_MAX,
                           NULL, NULL, 0);
             }
             thread_cpu = NULL;
-            object_unref(OBJECT(cpu));
             g_free(ts);
             rcu_unregister_thread();
             pthread_exit(NULL);
         }
 
-        cpu_list_unlock();
+        pthread_mutex_unlock(&clone_lock);
         preexit_cleanup(cpu_env, arg1);
         _exit(arg1);
         return 0; /* avoid warning */