__pthread_mutex_lock assertion error with a simple test program

[wanghanlin@xxxxxxxxxxxxxxxx]

Dear All,
Recently on my X86 server one problem hit.
../nptl/pthread_mutex_lock.c:81: __pthread_mutex_lock: Assertion `mutex->__data.__owner == 0' failed.
The test program of appendix [1] is very simple.
Strangely, there are hundreds of identical servers, but only two have this problem.

OS is debian 9.9 with kernel 4.9.0-3.
CPU model: Intel(R) Xeon(R) CPU E5-2680 v4 @ 2.40GHz
libc version: 2.24-11+deb9u4
gcc version:
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/6/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 6.3.0-18+deb9u1' --with-bugurl=file:///usr/share/doc/gcc-6/README.Bugs --enable-languages=c,ada,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-6 --program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new --enable-gnu-unique-object --disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-6-amd64/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-6-amd64 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-6-amd64 --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --with-target-system-zlib --enable-objc-gc=auto --enable-multiarch --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 6.3.0 20170516 (Debian 6.3.0-18+deb9u1)

appendix [1]:
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#define MAX_THREAD  50

static pthread_mutex_t seq_mutex = PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP;

static void *proc(void *arg)
{
    do {
        usleep(10);
        pthread_mutex_lock(&seq_mutex);
        pthread_mutex_unlock(&seq_mutex);
        pthread_mutex_lock(&seq_mutex);
        pthread_mutex_unlock(&seq_mutex);
    } while (1);
    return NULL;
}

int main()
{
    int err = 0;
    pthread_t thread[MAX_THREAD] = {0};
    pthread_attr_t attr;

    pthread_attr_init(&attr);
    for (int i = 0; i < MAX_THREAD; i++) {
        err = pthread_create(&thread[i], &attr, proc, NULL);
        if (err) {
            printf("create thread error");
            return 1;
        }
    }

    pthread_join(thread[0], NULL);
    return 0;
}

Regards & Thanks,
Hanlin