Possible deadlock issues

[ryancaicse]

It seems mutexp is not released before returning 422 and 427. Should it be a bug?

bfgminer/driver-modminer.c

Lines 404 to 427 in 8e0278a

	mutex_lock(mutexp);
	fd = modminer->device->device_fd;
	if (fd == -1) {
	// Died in another thread...
	mutex_unlock(mutexp);
	return false;
	}
	cmd[0] = MODMINER_GET_USERCODE;
	cmd[1] = fpgaid;
	if (write(fd, cmd, 2) != 2)
	bailout2(LOG_ERR, "%s: Error writing (read USER code)", modminer->proc_repr);
	if (serial_read(fd, buf, 4) != 4)
	bailout2(LOG_ERR, "%s: Error reading (read USER code)", modminer->proc_repr);
	if (memcmp(buf, BISTREAM_USER_ID, 4)) {
	applog(LOG_ERR, "%s: FPGA not programmed", modminer->proc_repr);
	if (!modminer_fpga_upload_bitstream(modminer))
	return false;
	} else if (opt_force_dev_init && !((struct modminer_fpga_state *)modminer->device->thr[0]->cgpu_data)->pdone) {
	applog(LOG_DEBUG, "%s: FPGA is already programmed, but --force-dev-init is set",
	modminer->proc_repr);
	if (!modminer_fpga_upload_bitstream(modminer))
	return false;

[ryancaicse]

Similar to the below. It may occur with very low probability

bfgminer/driver-proxy.c

Lines 95 to 115 in 8e0278a

	mutex_lock(&proxy_clients_mutex);
	HASH_FIND_STR(proxy_clients, username, client);
	if (!client)
	{
	user = strdup(username);
	cgpu = malloc(sizeof(*cgpu));
	client = malloc(sizeof(*client));
	*cgpu = (struct cgpu_info){
	.drv = &proxy_drv,
	.set_device_funcs = proxy_set_device_funcs,
	.threads = 0,
	.device_data = client,
	.device_path = user,
	};
	timer_set_now(&cgpu->cgminer_stats.start_tv);
	if (unlikely(!create_new_cgpus(add_cgpu_live, cgpu)))
	{
	free(client);
	free(cgpu);
	free(user);
	return NULL;