Re: [PATCH 1/3] md: restore bitmap/location to fix wrong bitmap offset while growing

> On Mar 6, 2026, at 06:50, kernel test robot <[email protected]> wrote:
> 
> Hi Su,
> 
> kernel test robot noticed the following build errors:
> 
> [auto build test ERROR on linus/master]
> [also build test ERROR on v7.0-rc2 next-20260305]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Su-Yue/md-restore-bitmap-location-to-fix-wrong-bitmap-offset-while-growing/20260303-114108
> base:   linus/master
> patch link:    https://lore.kernel.org/r/20260303033731.83885-2-glass.su%40suse.com
> patch subject: [PATCH 1/3] md: restore bitmap/location to fix wrong bitmap offset while growing
> config: i386-randconfig-051-20260305 (https://download.01.org/0day-ci/archive/20260306/[email protected]/config)
> compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260306/[email protected]/reproduce)
> 
> 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 <[email protected]>
> | Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
> 
> All errors (new ones prefixed by >>):
> 
>   ld: drivers/md/md.o: in function `md_alloc':
>>> drivers/md/md.c:6376:(.text+0xb36c): undefined reference to `md_sysfs_create_common_group'

Forget to test it with 

# CONFIG_MD_BITMAP is not set

Anyway, I will do  revision as Yu Kuai’s suggestion.

— 
Su

> 

> 
> vim +6376 drivers/md/md.c
> 
>  6276 
>  6277 struct mddev *md_alloc(dev_t dev, char *name)
>  6278 {
>  6279 /*
>  6280 * If dev is zero, name is the name of a device to allocate with
>  6281 * an arbitrary minor number.  It will be "md_???"
>  6282 * If dev is non-zero it must be a device number with a MAJOR of
>  6283 * MD_MAJOR or mdp_major.  In this case, if "name" is NULL, then
>  6284 * the device is being created by opening a node in /dev.
>  6285 * If "name" is not NULL, the device is being created by
>  6286 * writing to /sys/module/md_mod/parameters/new_array.
>  6287 */
>  6288 static DEFINE_MUTEX(disks_mutex);
>  6289 struct mddev *mddev;
>  6290 struct gendisk *disk;
>  6291 int partitioned;
>  6292 int shift;
>  6293 int unit;
>  6294 int error;
>  6295 
>  6296 /*
>  6297 * Wait for any previous instance of this device to be completely
>  6298 * removed (mddev_delayed_delete).
>  6299 */
>  6300 flush_workqueue(md_misc_wq);
>  6301 
>  6302 mutex_lock(&disks_mutex);
>  6303 mddev = mddev_alloc(dev);
>  6304 if (IS_ERR(mddev)) {
>  6305 error = PTR_ERR(mddev);
>  6306 goto out_unlock;
>  6307 }
>  6308 
>  6309 partitioned = (MAJOR(mddev->unit) != MD_MAJOR);
>  6310 shift = partitioned ? MdpMinorShift : 0;
>  6311 unit = MINOR(mddev->unit) >> shift;
>  6312 
>  6313 if (name && !dev) {
>  6314 /* Need to ensure that 'name' is not a duplicate.
>  6315 */
>  6316 struct mddev *mddev2;
>  6317 spin_lock(&all_mddevs_lock);
>  6318 
>  6319 list_for_each_entry(mddev2, &all_mddevs, all_mddevs)
>  6320 if (mddev2->gendisk &&
>  6321    strcmp(mddev2->gendisk->disk_name, name) == 0) {
>  6322 spin_unlock(&all_mddevs_lock);
>  6323 error = -EEXIST;
>  6324 goto out_free_mddev;
>  6325 }
>  6326 spin_unlock(&all_mddevs_lock);
>  6327 }
>  6328 if (name && dev)
>  6329 /*
>  6330 * Creating /dev/mdNNN via "newarray", so adjust hold_active.
>  6331 */
>  6332 mddev->hold_active = UNTIL_STOP;
>  6333 
>  6334 disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
>  6335 if (IS_ERR(disk)) {
>  6336 error = PTR_ERR(disk);
>  6337 goto out_free_mddev;
>  6338 }
>  6339 
>  6340 disk->major = MAJOR(mddev->unit);
>  6341 disk->first_minor = unit << shift;
>  6342 disk->minors = 1 << shift;
>  6343 if (name)
>  6344 strcpy(disk->disk_name, name);
>  6345 else if (partitioned)
>  6346 sprintf(disk->disk_name, "md_d%d", unit);
>  6347 else
>  6348 sprintf(disk->disk_name, "md%d", unit);
>  6349 disk->fops = &md_fops;
>  6350 disk->private_data = mddev;
>  6351 
>  6352 disk->events |= DISK_EVENT_MEDIA_CHANGE;
>  6353 mddev->gendisk = disk;
>  6354 error = add_disk(disk);
>  6355 if (error)
>  6356 goto out_put_disk;
>  6357 
>  6358 kobject_init(&mddev->kobj, &md_ktype);
>  6359 error = kobject_add(&mddev->kobj, &disk_to_dev(disk)->kobj, "%s", "md");
>  6360 if (error) {
>  6361 /*
>  6362 * The disk is already live at this point.  Clear the hold flag
>  6363 * and let mddev_put take care of the deletion, as it isn't any
>  6364 * different from a normal close on last release now.
>  6365 */
>  6366 mddev->hold_active = 0;
>  6367 mutex_unlock(&disks_mutex);
>  6368 mddev_put(mddev);
>  6369 return ERR_PTR(error);
>  6370 }
>  6371 
>  6372 /*
>  6373 * md_sysfs_remove_common_group is not needed because mddev_delayed_delete
>  6374 * calls kobject_put(&mddev->kobj) if mddev is to be deleted.
>  6375 */
>> 6376 if (md_sysfs_create_common_group(mddev))
>  6377 pr_warn("md: cannot register common bitmap attributes for %s\n",
>  6378 mdname(mddev));
>  6379 
>  6380 kobject_uevent(&mddev->kobj, KOBJ_ADD);
>  6381 mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state");
>  6382 mddev->sysfs_level = sysfs_get_dirent_safe(mddev->kobj.sd, "level");
>  6383 mutex_unlock(&disks_mutex);
>  6384 return mddev;
>  6385 
>  6386 out_put_disk:
>  6387 put_disk(disk);
>  6388 out_free_mddev:
>  6389 mddev_free(mddev);
>  6390 out_unlock:
>  6391 mutex_unlock(&disks_mutex);
>  6392 return ERR_PTR(error);
>  6393 }
>  6394 
> 
> -- 
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