今天在给服务器做LVM的时候（服务器的系统是CentOS 6.3），用fdisk分区之后，用w写入分区表的时候，就提示
Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8) Syncing disks.
退出fdisk之后，用partprobe直接通知内核重读分区表，出现如下问题：
Warning: WARNING: the kernel failed to re-read the partition table on /dev/sda (设备或资源忙). As a result, it may not reflect all of your changes until after reboot.
尝试用
partx -a /dev/sda

BLKPG: Device or resource busy
error adding partition 1
BLKPG: Device or resource busy
error adding partition 2
BLKPG: Device or resource busy
error adding partition 3
BLKPG: Device or resource busy
error adding partition 4
BLKPG: Device or resource busy
error adding partition 5
BLKPG: Device or resource busy
error adding partition 6
BLKPG: Device or resource busy
error adding partition 7
BLKPG: Device or resource busy
error adding partition 8
出现上面输出。

解决方案：

假设新增的分区是/dev/sda9，那么执行partx -a /dev/sda9 /dev/sda就可以了，

试过partprobe; partprobe /dev/sda9(提示找不到此设备); partx -a /dev/sda​（跟你提示的一样）都不行，最后网上查到partx -a /dev/sda9 /dev/sda才成功​，希望能可以提供给初学者参考。