读《understanding linux kernel》时的一个问题

[xilihuala]

在中断异常一章有这么一句话：
An interrupt handler may preempt both other interrupt handlers and exception handlers.
Conversely, an exception handler never preempts an interrupt handler. The only exception
that can be triggered in Kernel Mode is Page Fault, which we just described. But interrupt
handlers never perform operations that can induce Page Faults, and thus, potentially,
process switch.

我不能理解的是最后一句，在中断中不会产生“页错误”，为什么呢？