Hi Damien, url: https://github.com/0day-ci/linux/commits/Damien-Le-Moal/Initial-support-for-multi-actuator-HDDs/20210721-185447 base: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-next config: x86_64-randconfig-m001-20210720 (attached as .config) compiler: gcc-10 (Ubuntu 10.3.0-1ubuntu1~20.04) 10.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> smatch warnings: drivers/scsi/sd.c:3204 sd_read_cpr() error: uninitialized symbol 'buffer'. vim +/buffer +3204 drivers/scsi/sd.c 331fc9cf44c011 Damien Le Moal 2021-07-21 3137 static void sd_read_cpr(struct scsi_disk *sdkp) 331fc9cf44c011 Damien Le Moal 2021-07-21 3138 { 331fc9cf44c011 Damien Le Moal 2021-07-21 3139 unsigned char *buffer, *desc; ^^^^^^ 331fc9cf44c011 Damien Le Moal 2021-07-21 3140 struct blk_cranges *cr = NULL; 331fc9cf44c011 Damien Le Moal 2021-07-21 3141 unsigned int nr_cpr = 0; 331fc9cf44c011 Damien Le Moal 2021-07-21 3142 int i, vpd_len, buf_len = SD_BUF_SIZE; 331fc9cf44c011 Damien Le Moal 2021-07-21 3143 331fc9cf44c011 Damien Le Moal 2021-07-21 3144 /* 331fc9cf44c011 Damien Le Moal 2021-07-21 3145 * We need to have the capacity set first for the block layer to be 331fc9cf44c011 Damien Le Moal 2021-07-21 3146 * able to check the ranges. 331fc9cf44c011 Damien Le Moal 2021-07-21 3147 */ 331fc9cf44c011 Damien Le Moal 2021-07-21 3148 if (sdkp->first_scan) 331fc9cf44c011 Damien Le Moal 2021-07-21 3149 return; 331fc9cf44c011 Damien Le Moal 2021-07-21 3150 331fc9cf44c011 Damien Le Moal 2021-07-21 3151 if (!sdkp->capacity) 331fc9cf44c011 Damien Le Moal 2021-07-21 3152 goto out; ^^^^^^^^^ This should just return probably? 331fc9cf44c011 Damien Le Moal 2021-07-21 3153 331fc9cf44c011 Damien Le Moal 2021-07-21 3154 /* 331fc9cf44c011 Damien Le Moal 2021-07-21 3155 * Concurrent Positioning Ranges VPD: there can be at most 256 ranges, 331fc9cf44c011 Damien Le Moal 2021-07-21 3156 * leading to a maximum page size of 64 + 256*32 bytes. 331fc9cf44c011 Damien Le Moal 2021-07-21 3157 */ 331fc9cf44c011 Damien Le Moal 2021-07-21 3158 buf_len = 64 + 256*32; 331fc9cf44c011 Damien Le Moal 2021-07-21 3159 buffer = kmalloc(buf_len, GFP_KERNEL); 331fc9cf44c011 Damien Le Moal 2021-07-21 3160 if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb9, buffer, buf_len)) 331fc9cf44c011 Damien Le Moal 2021-07-21 3161 goto out; 331fc9cf44c011 Damien Le Moal 2021-07-21 3162 331fc9cf44c011 Damien Le Moal 2021-07-21 3163 /* We must have at least a 64B header and one 32B range descriptor */ 331fc9cf44c011 Damien Le Moal 2021-07-21 3164 vpd_len = get_unaligned_be16(&buffer[2]) + 3; 331fc9cf44c011 Damien Le Moal 2021-07-21 3165 if (vpd_len > buf_len || vpd_len < 64 + 32 || (vpd_len & 31)) { 331fc9cf44c011 Damien Le Moal 2021-07-21 3166 sd_printk(KERN_ERR, sdkp, 331fc9cf44c011 Damien Le Moal 2021-07-21 3167 "Invalid Concurrent Positioning Ranges VPD page\n"); 331fc9cf44c011 Damien Le Moal 2021-07-21 3168 goto out; 331fc9cf44c011 Damien Le Moal 2021-07-21 3169 } 331fc9cf44c011 Damien Le Moal 2021-07-21 3170 331fc9cf44c011 Damien Le Moal 2021-07-21 3171 nr_cpr = (vpd_len - 64) / 32; 331fc9cf44c011 Damien Le Moal 2021-07-21 3172 if (nr_cpr == 1) { 331fc9cf44c011 Damien Le Moal 2021-07-21 3173 nr_cpr = 0; 331fc9cf44c011 Damien Le Moal 2021-07-21 3174 goto out; 331fc9cf44c011 Damien Le Moal 2021-07-21 3175 } 331fc9cf44c011 Damien Le Moal 2021-07-21 3176 331fc9cf44c011 Damien Le Moal 2021-07-21 3177 cr = blk_alloc_cranges(sdkp->disk, nr_cpr); 331fc9cf44c011 Damien Le Moal 2021-07-21 3178 if (!cr) { 331fc9cf44c011 Damien Le Moal 2021-07-21 3179 nr_cpr = 0; 331fc9cf44c011 Damien Le Moal 2021-07-21 3180 goto out; 331fc9cf44c011 Damien Le Moal 2021-07-21 3181 } 331fc9cf44c011 Damien Le Moal 2021-07-21 3182 331fc9cf44c011 Damien Le Moal 2021-07-21 3183 desc = &buffer[64]; 331fc9cf44c011 Damien Le Moal 2021-07-21 3184 for (i = 0; i < nr_cpr; i++, desc += 32) { 331fc9cf44c011 Damien Le Moal 2021-07-21 3185 if (desc[0] != i) { 331fc9cf44c011 Damien Le Moal 2021-07-21 3186 sd_printk(KERN_ERR, sdkp, 331fc9cf44c011 Damien Le Moal 2021-07-21 3187 "Invalid Concurrent Positioning Range number\n"); 331fc9cf44c011 Damien Le Moal 2021-07-21 3188 nr_cpr = 0; 331fc9cf44c011 Damien Le Moal 2021-07-21 3189 break; 331fc9cf44c011 Damien Le Moal 2021-07-21 3190 } 331fc9cf44c011 Damien Le Moal 2021-07-21 3191 331fc9cf44c011 Damien Le Moal 2021-07-21 3192 cr->ranges[i].sector = sd64_to_sectors(sdkp, desc + 8); 331fc9cf44c011 Damien Le Moal 2021-07-21 3193 cr->ranges[i].nr_sectors = sd64_to_sectors(sdkp, desc + 16); 331fc9cf44c011 Damien Le Moal 2021-07-21 3194 } 331fc9cf44c011 Damien Le Moal 2021-07-21 3195 331fc9cf44c011 Damien Le Moal 2021-07-21 3196 out: 331fc9cf44c011 Damien Le Moal 2021-07-21 3197 blk_queue_set_cranges(sdkp->disk, cr); 331fc9cf44c011 Damien Le Moal 2021-07-21 3198 if (nr_cpr && sdkp->nr_actuators != nr_cpr) { 331fc9cf44c011 Damien Le Moal 2021-07-21 3199 sd_printk(KERN_NOTICE, sdkp, 331fc9cf44c011 Damien Le Moal 2021-07-21 3200 "%u concurrent positioning ranges\n", nr_cpr); 331fc9cf44c011 Damien Le Moal 2021-07-21 3201 sdkp->nr_actuators = nr_cpr; 331fc9cf44c011 Damien Le Moal 2021-07-21 3202 } 331fc9cf44c011 Damien Le Moal 2021-07-21 3203 331fc9cf44c011 Damien Le Moal 2021-07-21 @3204 kfree(buffer); ^^^^^^^^^^^^^ 331fc9cf44c011 Damien Le Moal 2021-07-21 3205 } --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx