[Qemu-devel] [PATCH] The QEMU crashes since invoking qemu_thread_set_name(), the backtrace is:

[zhanghailiang]

From: Caoxinhua <address@hidden>

(gdb) bt
#0 0x00007f9a68b095d7 in __GI_raise (address@hidden) at 
../nptl/sysdeps/unix/sysv/linux/raise.c:56
#1 0x00007f9a68b0acc8 in __GI_abort () at abort.c:90
#2 0x00007f9a69cda389 in PAT_abort () from /usr/lib64/libuvpuserhotfix.so
#3 0x00007f9a69cdda0d in patchIllInsHandler () from 
/usr/lib64/libuvpuserhotfix.so
#4 <signal handler called>
#5 pthread_setname_np (th=140298470549248, address@hidden "io-task-worker") at 
../nptl/sysdeps/unix/sysv/linux/pthread_setname.c:49
#6 0x00000000007f5f20 in qemu_thread_set_name (address@hidden, address@hidden 
"io-task-worker") at util/qemu_thread_posix.c:459
#7 0x00000000007f679e in qemu_thread_create (address@hidden, address@hidden 
"io-task-worker",address@hidden <qio_task_thread_worker>, address@hidden, 
address@hidden) at util/qemu_thread_posix.c:498
#8 0x00000000007c15b6 in qio_task_run_in_thread (address@hidden, address@hidden 
<qio_channel_socket_connect_worker>, opaque=0x7f99b8003370, destroy=0x7c6220 
<qapi_free_SocketAddress>) at io/task.c:133
#9 0x00000000007bda04 in qio_channel_socket_connect_async (ioc=0x7f99b80014c0, 
addr=0x37235d0, address@hidden <qemu_chr_socket_connected>, address@hidden, 
address@hidden) at io/channel_socket.c:191
#10 0x00000000005487f6 in socket_reconnect_timeout (opaque=0x38118b0) at 
qemu_char.c:4402
#11 0x00007f9a6a1533b3 in g_timeout_dispatch () from /usr/lib64/libglib-2.0.so.0
#12 0x00007f9a6a15299a in g_main_context_dispatch () from 
/usr/lib64/libglib-2.0.so.0
#13 0x0000000000747386 in glib_pollfds_poll () at main_loop.c:227
#14 0x0000000000747424 in os_host_main_loop_wait (timeout=404000000) at 
main_loop.c:272
#15 0x0000000000747575 in main_loop_wait (address@hidden) at main_loop.c:520
#16 0x0000000000557d31 in main_loop () at vl.c:2170
#17 0x000000000041c8b7 in main (argc=<optimized out>, argv=<optimized out>, 
envp=<optimized out>) at vl.c:5083

That's because the corresponding child thread has been exited before the main 
thread calling qemu_thread_set_name().
Let's detach the thread after calling qemu_thread_set_name().

Signed-off-by: Caoxinhua <address@hidden>
---
 util/qemu-thread-posix.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
index d20cdde..d31793d 100644
--- a/util/qemu-thread-posix.c
+++ b/util/qemu-thread-posix.c
@@ -481,12 +481,6 @@ void qemu_thread_create(QemuThread *thread, const char 
*name,
     if (err) {
         error_exit(err, __func__);
     }
-    if (mode == QEMU_THREAD_DETACHED) {
-        err = pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
-        if (err) {
-            error_exit(err, __func__);
-        }
-    }
 
     /* Leave signal handling to the iothread.  */
     sigfillset(&set);
@@ -499,6 +493,12 @@ void qemu_thread_create(QemuThread *thread, const char 
*name,
         qemu_thread_set_name(thread, name);
     }
 
+    if (mode == QEMU_THREAD_DETACHED) {
+        err = pthread_detach(thread->thread);
+        if (err) {
+            error_exit(err, __func__);
+        }
+    }
     pthread_sigmask(SIG_SETMASK, &oldset, NULL);
 
     pthread_attr_destroy(&attr);
-- 
1.8.3.1