[Qemu-devel] question: guest will hang when call system function in migration thread.

[陈梁]

Hi all

guest will hang when call system function in migration thread. The cpu usage of 
vcpu thread is 100%.

the code like this:

static void *migration_thread(void *opaque)
{
    MigrationState *s = opaque;
    int64_t initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
    int64_t setup_start = qemu_clock_get_ms(QEMU_CLOCK_HOST);
    int64_t initial_bytes = 0;
    int64_t max_size = 0;
    int64_t start_time = initial_time;
    bool old_vm_running = false;

    //test code
    system("df -h”);        

    qemu_savevm_state_begin(s->file, &s->params);
    …

Is it anything wrong?  or it is not allow to call system in migration thread?