Why BOOT_PRINTK_DELAY "may adversely affect SMP systems"?

Hi experts,

I noticed there is an kernel option called BOOT_PRINTK_DELAY and some warning messages in the Kconfig file as below:

NOTE: Using this option may adversely affect SMP systems. I.e., processors other than the first one may not boot up. BOOT_PRINTK_DELAY also may cause DETECT_SOFTLOCKUP to detect what it believes to be lockup conditions.

As my understanding, this do nothing but just let the very CPU loop for a while and shouldn't cause any affect on the boot process. So I can hardly understand WHY it may cause "processors other than the first one may not boot up"? If this issue can be avoid/fixed?

Thanks a lot!
Snakky