[Q] vmalloc and interrupt handler

From: Tsuyoshi (bz800k_at_hotmail.com)
Date: 04/22/04

  • Next message: tcs: "kernel thread" 
    Date: 21 Apr 2004 19:37:33 -0700

    Hi.
    I'm trying to write a simple device driver using a lot of memory.
    It seems that vmalloc() is not available in interrupt handler, because
    it may sleep.

    So, I changed my code such that vmalloc() is only called in driver's open function,
    and interrupt handler only access the memory already allocated by vmalloc().

    Then I have a question.
    Does this memory area allocated by vmalloc() have a possibility to be paged out?
    If this area paged out, interrupt handler cannot access the area(because
    interrupt handler must sleep until page-in handler done.)

    Please help me.
    Thanks !!!

  • Next message: tcs: "kernel thread"

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