tree: https://github.com/AsahiLinux/linux bits/090-spi-hid head: ecf1fb81499a2f1724cb90497ca3c1cec831c9b6 commit: 51f1f2b38adcb95f2e04665ae54fe99ba6bd7844 [18/22] soc: apple: Add RTKit helper driver config: arm-randconfig-m041-20220918 compiler: arm-linux-gnueabi-gcc (GCC) 12.1.0 If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: drivers/soc/apple/rtkit-helper.c:46 apple_rtkit_helper_shmem_setup() warn: variable dereferenced before check 'helper->sram' (see line 35) vim +46 drivers/soc/apple/rtkit-helper.c 51f1f2b38adcb9 Hector Martin 2022-07-03 28 static int apple_rtkit_helper_shmem_setup(void *cookie, struct apple_rtkit_shmem *bfr) 51f1f2b38adcb9 Hector Martin 2022-07-03 29 { 51f1f2b38adcb9 Hector Martin 2022-07-03 30 struct apple_rtkit_helper *helper = cookie; 51f1f2b38adcb9 Hector Martin 2022-07-03 31 struct resource res = { 51f1f2b38adcb9 Hector Martin 2022-07-03 32 .start = bfr->iova, 51f1f2b38adcb9 Hector Martin 2022-07-03 33 .end = bfr->iova + bfr->size - 1, 51f1f2b38adcb9 Hector Martin 2022-07-03 34 .name = "rtkit_map", 51f1f2b38adcb9 Hector Martin 2022-07-03 @35 .flags = helper->sram->flags, ^^^^^^^^^^^^^ Dereference 51f1f2b38adcb9 Hector Martin 2022-07-03 36 }; 51f1f2b38adcb9 Hector Martin 2022-07-03 37 51f1f2b38adcb9 Hector Martin 2022-07-03 38 if (!bfr->iova) { 51f1f2b38adcb9 Hector Martin 2022-07-03 39 bfr->buffer = dma_alloc_coherent(helper->dev, bfr->size, 51f1f2b38adcb9 Hector Martin 2022-07-03 40 &bfr->iova, GFP_KERNEL); 51f1f2b38adcb9 Hector Martin 2022-07-03 41 if (!bfr->buffer) 51f1f2b38adcb9 Hector Martin 2022-07-03 42 return -ENOMEM; 51f1f2b38adcb9 Hector Martin 2022-07-03 43 return 0; 51f1f2b38adcb9 Hector Martin 2022-07-03 44 } 51f1f2b38adcb9 Hector Martin 2022-07-03 45 51f1f2b38adcb9 Hector Martin 2022-07-03 @46 if (!helper->sram) { ^^^^^^^^^^^^ Checked too late. 51f1f2b38adcb9 Hector Martin 2022-07-03 47 dev_err(helper->dev, 51f1f2b38adcb9 Hector Martin 2022-07-03 48 "RTKit buffer request with no SRAM region: %pR", &res); 51f1f2b38adcb9 Hector Martin 2022-07-03 49 return -EFAULT; 51f1f2b38adcb9 Hector Martin 2022-07-03 50 } 51f1f2b38adcb9 Hector Martin 2022-07-03 51 51f1f2b38adcb9 Hector Martin 2022-07-03 52 if (res.end < res.start || !resource_contains(helper->sram, &res)) { 51f1f2b38adcb9 Hector Martin 2022-07-03 53 dev_err(helper->dev, 51f1f2b38adcb9 Hector Martin 2022-07-03 54 "RTKit buffer request outside SRAM region: %pR", &res); 51f1f2b38adcb9 Hector Martin 2022-07-03 55 return -EFAULT; 51f1f2b38adcb9 Hector Martin 2022-07-03 56 } 51f1f2b38adcb9 Hector Martin 2022-07-03 57 51f1f2b38adcb9 Hector Martin 2022-07-03 58 bfr->iomem = helper->sram_base + (res.start - helper->sram->start); 51f1f2b38adcb9 Hector Martin 2022-07-03 59 bfr->is_mapped = true; 51f1f2b38adcb9 Hector Martin 2022-07-03 60 51f1f2b38adcb9 Hector Martin 2022-07-03 61 return 0; 51f1f2b38adcb9 Hector Martin 2022-07-03 62 }