Hi Wentao,
kernel test robot noticed the following build warnings:
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Wentao-Liang/i2c-qup-Add-erro... base: https://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux.git i2c/i2c-host patch link: https://lore.kernel.org/r/20250519141918.2522-1-vulab%40iscas.ac.cn patch subject: [PATCH] i2c: qup: Add error handling in qup_i2c_xfer_v2() config: powerpc64-randconfig-r071-20250522 (https://download.01.org/0day-ci/archive/20250522/202505221445.quJVHqSz-lkp@i...) compiler: clang version 21.0.0git (https://github.com/llvm/llvm-project f819f46284f2a79790038e1f6649172789734ae8)
If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot lkp@intel.com | Reported-by: Dan Carpenter dan.carpenter@linaro.org | Closes: https://lore.kernel.org/r/202505221445.quJVHqSz-lkp@intel.com/
smatch warnings: drivers/i2c/busses/i2c-qup.c:1621 qup_i2c_xfer_v2() error: uninitialized symbol 'err'.
vim +/err +1621 drivers/i2c/busses/i2c-qup.c
191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1565 static int qup_i2c_xfer_v2(struct i2c_adapter *adap, 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1566 struct i2c_msg msgs[], 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1567 int num) 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1568 { 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1569 struct qup_i2c_dev *qup = i2c_get_adapdata(adap); 61f647e9d36d67 Wentao Liang 2025-05-19 1570 int ret, err, idx = 0; 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1571 fbf9921f8b35d9 Sricharan Ramabadhran 2016-06-10 1572 qup->bus_err = 0; fbf9921f8b35d9 Sricharan Ramabadhran 2016-06-10 1573 qup->qup_err = 0; fbf9921f8b35d9 Sricharan Ramabadhran 2016-06-10 1574 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1575 ret = pm_runtime_get_sync(qup->dev); 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1576 if (ret < 0) 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1577 goto out; 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1578 7545c7dba169c4 Abhishek Sahu 2018-03-12 1579 ret = qup_i2c_determine_mode_v2(qup, msgs, num); 7545c7dba169c4 Abhishek Sahu 2018-03-12 1580 if (ret) 7545c7dba169c4 Abhishek Sahu 2018-03-12 1581 goto out; 7545c7dba169c4 Abhishek Sahu 2018-03-12 1582 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1583 writel(1, qup->base + QUP_SW_RESET); 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1584 ret = qup_i2c_poll_state(qup, QUP_RESET_STATE); 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1585 if (ret) 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1586 goto out; 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1587 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1588 /* Configure QUP as I2C mini core */ 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1589 writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG); 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1590 writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN); 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1591 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1592 if (qup_i2c_poll_state_i2c_master(qup)) { 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1593 ret = -EIO; 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1594 goto out; 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1595 } 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1596 eb422b539c1f39 Abhishek Sahu 2018-03-12 1597 if (qup->use_dma) { 7545c7dba169c4 Abhishek Sahu 2018-03-12 1598 reinit_completion(&qup->xfer); 7545c7dba169c4 Abhishek Sahu 2018-03-12 1599 ret = qup_i2c_bam_xfer(adap, &msgs[0], num); eb422b539c1f39 Abhishek Sahu 2018-03-12 1600 qup->use_dma = false; 9cedf3b2f09946 Sricharan Ramabadhran 2016-02-22 1601 } else { 7545c7dba169c4 Abhishek Sahu 2018-03-12 1602 qup_i2c_conf_mode_v2(qup); 7545c7dba169c4 Abhishek Sahu 2018-03-12 1603 7545c7dba169c4 Abhishek Sahu 2018-03-12 1604 for (idx = 0; idx < num; idx++) { 7545c7dba169c4 Abhishek Sahu 2018-03-12 1605 qup->msg = &msgs[idx]; 7545c7dba169c4 Abhishek Sahu 2018-03-12 1606 qup->is_last = idx == (num - 1); 7545c7dba169c4 Abhishek Sahu 2018-03-12 1607 7545c7dba169c4 Abhishek Sahu 2018-03-12 1608 ret = qup_i2c_xfer_v2_msg(qup, idx, 7545c7dba169c4 Abhishek Sahu 2018-03-12 1609 !!(msgs[idx].flags & I2C_M_RD)); 7545c7dba169c4 Abhishek Sahu 2018-03-12 1610 if (ret) 7545c7dba169c4 Abhishek Sahu 2018-03-12 1611 break; 7545c7dba169c4 Abhishek Sahu 2018-03-12 1612 } 7545c7dba169c4 Abhishek Sahu 2018-03-12 1613 qup->msg = NULL; 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1614 } 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1615 f74187932d30e4 Sricharan Ramabadhran 2016-01-19 1616 if (!ret) 7545c7dba169c4 Abhishek Sahu 2018-03-12 1617 ret = qup_i2c_bus_active(qup, ONE_BYTE); 7545c7dba169c4 Abhishek Sahu 2018-03-12 1618 7545c7dba169c4 Abhishek Sahu 2018-03-12 1619 if (!ret) 61f647e9d36d67 Wentao Liang 2025-05-19 1620 err = qup_i2c_change_state(qup, QUP_RESET_STATE);
if ret was already set then err isn't initialized.
61f647e9d36d67 Wentao Liang 2025-05-19 @1621 if (err) ^^^ Uninitialized. In production obviously the only sane choice is CONFIG_INIT_STACK_ALL_ZERO but I really encourage developers to set CONFIG_INIT_STACK_ALL_PATTERN=y so that we catch these sorts of bugs in testing.
61f647e9d36d67 Wentao Liang 2025-05-19 1622 return err; f74187932d30e4 Sricharan Ramabadhran 2016-01-19 1623 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1624 if (ret == 0) 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1625 ret = num; 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1626 out: 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1627 pm_runtime_mark_last_busy(qup->dev); 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1628 pm_runtime_put_autosuspend(qup->dev); 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1629 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1630 return ret; 191424bb6166f6 Sricharan Ramabadhran 2016-01-19 1631 }