Hi Herbert, I love your patch! Yet something to improve: [auto build test ERROR on cryptodev/master] [also build test ERROR on crypto/master rockchip/for-next v5.7 next-20200611] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Herbert-Xu/crypto-algapi-Remove-... base: https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master config: m68k-allmodconfig (attached as .config) compiler: m68k-linux-gcc (GCC) 9.3.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=m68k If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>, old ones prefixed by <<): drivers/crypto/qcom-rng.c: In function 'qcom_rng_read': 48 | val = readl_relaxed(rng->base + PRNG_STATUS); | ^~~~~~~~~~~~~ drivers/crypto/qcom-rng.c: In function 'qcom_rng_enable': 115 | writel(val, rng->base + PRNG_LFSR_CFG); | ^~~~~~ cc1: some warnings being treated as errors vim +/readl_relaxed +48 drivers/crypto/qcom-rng.c ceec5f5b59882b Vinod Koul 2018-07-16 40 ceec5f5b59882b Vinod Koul 2018-07-16 41 static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max) ceec5f5b59882b Vinod Koul 2018-07-16 42 { ceec5f5b59882b Vinod Koul 2018-07-16 43 unsigned int currsize = 0; ceec5f5b59882b Vinod Koul 2018-07-16 44 u32 val; ceec5f5b59882b Vinod Koul 2018-07-16 45 ceec5f5b59882b Vinod Koul 2018-07-16 46 /* read random data from hardware */ ceec5f5b59882b Vinod Koul 2018-07-16 47 do { ceec5f5b59882b Vinod Koul 2018-07-16 @48 val = readl_relaxed(rng->base + PRNG_STATUS); ceec5f5b59882b Vinod Koul 2018-07-16 49 if (!(val & PRNG_STATUS_DATA_AVAIL)) ceec5f5b59882b Vinod Koul 2018-07-16 50 break; ceec5f5b59882b Vinod Koul 2018-07-16 51 ceec5f5b59882b Vinod Koul 2018-07-16 52 val = readl_relaxed(rng->base + PRNG_DATA_OUT); ceec5f5b59882b Vinod Koul 2018-07-16 53 if (!val) ceec5f5b59882b Vinod Koul 2018-07-16 54 break; ceec5f5b59882b Vinod Koul 2018-07-16 55 ceec5f5b59882b Vinod Koul 2018-07-16 56 if ((max - currsize) >= WORD_SZ) { ceec5f5b59882b Vinod Koul 2018-07-16 57 memcpy(data, &val, WORD_SZ); ceec5f5b59882b Vinod Koul 2018-07-16 58 data += WORD_SZ; ceec5f5b59882b Vinod Koul 2018-07-16 59 currsize += WORD_SZ; ceec5f5b59882b Vinod Koul 2018-07-16 60 } else { ceec5f5b59882b Vinod Koul 2018-07-16 61 /* copy only remaining bytes */ ceec5f5b59882b Vinod Koul 2018-07-16 62 memcpy(data, &val, max - currsize); ceec5f5b59882b Vinod Koul 2018-07-16 63 break; ceec5f5b59882b Vinod Koul 2018-07-16 64 } ceec5f5b59882b Vinod Koul 2018-07-16 65 } while (currsize < max); ceec5f5b59882b Vinod Koul 2018-07-16 66 ceec5f5b59882b Vinod Koul 2018-07-16 67 return currsize; ceec5f5b59882b Vinod Koul 2018-07-16 68 } ceec5f5b59882b Vinod Koul 2018-07-16 69 ceec5f5b59882b Vinod Koul 2018-07-16 70 static int qcom_rng_generate(struct crypto_rng *tfm, ceec5f5b59882b Vinod Koul 2018-07-16 71 const u8 *src, unsigned int slen, ceec5f5b59882b Vinod Koul 2018-07-16 72 u8 *dstn, unsigned int dlen) ceec5f5b59882b Vinod Koul 2018-07-16 73 { ceec5f5b59882b Vinod Koul 2018-07-16 74 struct qcom_rng_ctx *ctx = crypto_rng_ctx(tfm); ceec5f5b59882b Vinod Koul 2018-07-16 75 struct qcom_rng *rng = ctx->rng; ceec5f5b59882b Vinod Koul 2018-07-16 76 int ret; ceec5f5b59882b Vinod Koul 2018-07-16 77 ceec5f5b59882b Vinod Koul 2018-07-16 78 ret = clk_prepare_enable(rng->clk); ceec5f5b59882b Vinod Koul 2018-07-16 79 if (ret) ceec5f5b59882b Vinod Koul 2018-07-16 80 return ret; ceec5f5b59882b Vinod Koul 2018-07-16 81 ceec5f5b59882b Vinod Koul 2018-07-16 82 mutex_lock(&rng->lock); ceec5f5b59882b Vinod Koul 2018-07-16 83 ceec5f5b59882b Vinod Koul 2018-07-16 84 ret = qcom_rng_read(rng, dstn, dlen); ceec5f5b59882b Vinod Koul 2018-07-16 85 ceec5f5b59882b Vinod Koul 2018-07-16 86 mutex_unlock(&rng->lock); ceec5f5b59882b Vinod Koul 2018-07-16 87 clk_disable_unprepare(rng->clk); ceec5f5b59882b Vinod Koul 2018-07-16 88 ceec5f5b59882b Vinod Koul 2018-07-16 89 return 0; ceec5f5b59882b Vinod Koul 2018-07-16 90 } ceec5f5b59882b Vinod Koul 2018-07-16 91 ceec5f5b59882b Vinod Koul 2018-07-16 92 static int qcom_rng_seed(struct crypto_rng *tfm, const u8 *seed, ceec5f5b59882b Vinod Koul 2018-07-16 93 unsigned int slen) ceec5f5b59882b Vinod Koul 2018-07-16 94 { ceec5f5b59882b Vinod Koul 2018-07-16 95 return 0; ceec5f5b59882b Vinod Koul 2018-07-16 96 } ceec5f5b59882b Vinod Koul 2018-07-16 97 ceec5f5b59882b Vinod Koul 2018-07-16 98 static int qcom_rng_enable(struct qcom_rng *rng) ceec5f5b59882b Vinod Koul 2018-07-16 99 { ceec5f5b59882b Vinod Koul 2018-07-16 100 u32 val; ceec5f5b59882b Vinod Koul 2018-07-16 101 int ret; ceec5f5b59882b Vinod Koul 2018-07-16 102 ceec5f5b59882b Vinod Koul 2018-07-16 103 ret = clk_prepare_enable(rng->clk); ceec5f5b59882b Vinod Koul 2018-07-16 104 if (ret) ceec5f5b59882b Vinod Koul 2018-07-16 105 return ret; ceec5f5b59882b Vinod Koul 2018-07-16 106 ceec5f5b59882b Vinod Koul 2018-07-16 107 /* Enable PRNG only if it is not already enabled */ ceec5f5b59882b Vinod Koul 2018-07-16 108 val = readl_relaxed(rng->base + PRNG_CONFIG); ceec5f5b59882b Vinod Koul 2018-07-16 109 if (val & PRNG_CONFIG_HW_ENABLE) ceec5f5b59882b Vinod Koul 2018-07-16 110 goto already_enabled; ceec5f5b59882b Vinod Koul 2018-07-16 111 ceec5f5b59882b Vinod Koul 2018-07-16 112 val = readl_relaxed(rng->base + PRNG_LFSR_CFG); ceec5f5b59882b Vinod Koul 2018-07-16 113 val &= ~PRNG_LFSR_CFG_MASK; ceec5f5b59882b Vinod Koul 2018-07-16 114 val |= PRNG_LFSR_CFG_CLOCKS; ceec5f5b59882b Vinod Koul 2018-07-16 @115 writel(val, rng->base + PRNG_LFSR_CFG); ceec5f5b59882b Vinod Koul 2018-07-16 116 ceec5f5b59882b Vinod Koul 2018-07-16 117 val = readl_relaxed(rng->base + PRNG_CONFIG); ceec5f5b59882b Vinod Koul 2018-07-16 118 val |= PRNG_CONFIG_HW_ENABLE; ceec5f5b59882b Vinod Koul 2018-07-16 119 writel(val, rng->base + PRNG_CONFIG); ceec5f5b59882b Vinod Koul 2018-07-16 120 ceec5f5b59882b Vinod Koul 2018-07-16 121 already_enabled: ceec5f5b59882b Vinod Koul 2018-07-16 122 clk_disable_unprepare(rng->clk); ceec5f5b59882b Vinod Koul 2018-07-16 123 ceec5f5b59882b Vinod Koul 2018-07-16 124 return 0; ceec5f5b59882b Vinod Koul 2018-07-16 125 } ceec5f5b59882b Vinod Koul 2018-07-16 126 :::::: The code at line 48 was first introduced by commit :::::: ceec5f5b59882b871a722ca4d49b767a09a4bde9 crypto: qcom-rng - Add Qcom prng driver :::::: TO: Vinod Koul <vkoul(a)kernel.org&gt; :::::: CC: Herbert Xu <herbert(a)gondor.apana.org.au&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org