Hi,

url:    https://github.com/0day-ci/linux/commits/alexandru-tachici-analog-com/hwmon-pmbus-adm1266-add-support/20200728-002155
base:   https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git hwmon-next
config: x86_64-randconfig-m001-20200731 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-14) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/hwmon/pmbus/adm1266.c:88 adm1266_pmbus_block_xfer() warn: inconsistent returns 'data->buf_mutex'.

# https://github.com/0day-ci/linux/commit/878684621a66ce0c9e2bdd10f9232b07e48ede96
git remote add linux-review https://github.com/0day-ci/linux
git remote update linux-review
git checkout 878684621a66ce0c9e2bdd10f9232b07e48ede96
vim +88 drivers/hwmon/pmbus/adm1266.c

878684621a66ce0 Alexandru Tachici 2020-07-27  35  static int adm1266_pmbus_block_xfer(struct adm1266_data *data, u8 cmd, u8 w_len, u8 *data_w,
878684621a66ce0 Alexandru Tachici 2020-07-27  36  				    u8 *data_r)
878684621a66ce0 Alexandru Tachici 2020-07-27  37  {
878684621a66ce0 Alexandru Tachici 2020-07-27  38  	struct i2c_client *client = data->client;
878684621a66ce0 Alexandru Tachici 2020-07-27  39  	struct i2c_msg msgs[2] = {
878684621a66ce0 Alexandru Tachici 2020-07-27  40  		{
878684621a66ce0 Alexandru Tachici 2020-07-27  41  			.addr = client->addr,
878684621a66ce0 Alexandru Tachici 2020-07-27  42  			.flags = I2C_M_DMA_SAFE,
878684621a66ce0 Alexandru Tachici 2020-07-27  43  			.buf = data->write_buf,
878684621a66ce0 Alexandru Tachici 2020-07-27  44  			.len = w_len + 2,
878684621a66ce0 Alexandru Tachici 2020-07-27  45  		},
878684621a66ce0 Alexandru Tachici 2020-07-27  46  		{
878684621a66ce0 Alexandru Tachici 2020-07-27  47  			.addr = client->addr,
878684621a66ce0 Alexandru Tachici 2020-07-27  48  			.flags = I2C_M_RD | I2C_M_DMA_SAFE,
878684621a66ce0 Alexandru Tachici 2020-07-27  49  			.buf = data->read_buf,
878684621a66ce0 Alexandru Tachici 2020-07-27  50  			.len = ADM1266_PMBUS_BLOCK_MAX + 2,
878684621a66ce0 Alexandru Tachici 2020-07-27  51  		}
ac5fec412db3640 Alexandru Tachici 2020-07-27  52  	};
878684621a66ce0 Alexandru Tachici 2020-07-27  53  	u8 addr;
878684621a66ce0 Alexandru Tachici 2020-07-27  54  	u8 crc;
878684621a66ce0 Alexandru Tachici 2020-07-27  55  	int ret;
878684621a66ce0 Alexandru Tachici 2020-07-27  56  
878684621a66ce0 Alexandru Tachici 2020-07-27  57  	mutex_lock(&data->buf_mutex);
878684621a66ce0 Alexandru Tachici 2020-07-27  58  
878684621a66ce0 Alexandru Tachici 2020-07-27  59  	msgs[0].buf[0] = cmd;
878684621a66ce0 Alexandru Tachici 2020-07-27  60  	msgs[0].buf[1] = w_len;
878684621a66ce0 Alexandru Tachici 2020-07-27  61  	memcpy(&msgs[0].buf[2], data_w, w_len);
878684621a66ce0 Alexandru Tachici 2020-07-27  62  
878684621a66ce0 Alexandru Tachici 2020-07-27  63  	ret = i2c_transfer(client->adapter, msgs, 2);
878684621a66ce0 Alexandru Tachici 2020-07-27  64  	if (ret != 2) {
878684621a66ce0 Alexandru Tachici 2020-07-27  65  		if (ret >= 0)
878684621a66ce0 Alexandru Tachici 2020-07-27  66  			ret = -EPROTO;
878684621a66ce0 Alexandru Tachici 2020-07-27  67  		return ret;

Unlock

878684621a66ce0 Alexandru Tachici 2020-07-27  68  	}
878684621a66ce0 Alexandru Tachici 2020-07-27  69  
878684621a66ce0 Alexandru Tachici 2020-07-27  70  	if (client->flags & I2C_CLIENT_PEC) {
878684621a66ce0 Alexandru Tachici 2020-07-27  71  		addr = i2c_8bit_addr_from_msg(&msgs[0]);
878684621a66ce0 Alexandru Tachici 2020-07-27  72  		crc = crc8(pmbus_crc_table, &addr, 1, 0);
878684621a66ce0 Alexandru Tachici 2020-07-27  73  		crc = crc8(pmbus_crc_table, msgs[0].buf,  msgs[0].len, crc);
878684621a66ce0 Alexandru Tachici 2020-07-27  74  
878684621a66ce0 Alexandru Tachici 2020-07-27  75  		addr = i2c_8bit_addr_from_msg(&msgs[1]);
878684621a66ce0 Alexandru Tachici 2020-07-27  76  		crc = crc8(pmbus_crc_table, &addr, 1, crc);
878684621a66ce0 Alexandru Tachici 2020-07-27  77  		crc = crc8(pmbus_crc_table, msgs[1].buf,  msgs[1].buf[0] + 1, crc);
878684621a66ce0 Alexandru Tachici 2020-07-27  78  
878684621a66ce0 Alexandru Tachici 2020-07-27  79  		if (crc != msgs[1].buf[msgs[1].buf[0] + 1])
878684621a66ce0 Alexandru Tachici 2020-07-27  80  			return -EBADMSG;

And unlock here.

878684621a66ce0 Alexandru Tachici 2020-07-27  81  	}
878684621a66ce0 Alexandru Tachici 2020-07-27  82  
878684621a66ce0 Alexandru Tachici 2020-07-27  83  	memcpy(data_r, &msgs[1].buf[1], msgs[1].buf[0]);
878684621a66ce0 Alexandru Tachici 2020-07-27  84  
878684621a66ce0 Alexandru Tachici 2020-07-27  85  	ret = msgs[1].buf[0];
878684621a66ce0 Alexandru Tachici 2020-07-27  86  	mutex_unlock(&data->buf_mutex);
878684621a66ce0 Alexandru Tachici 2020-07-27  87  
878684621a66ce0 Alexandru Tachici 2020-07-27 @88  	return ret;
878684621a66ce0 Alexandru Tachici 2020-07-27  89  }

---
0-DAY CI Kernel Test Service, Intel Corporation
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