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Re: double fault
* Martin Hunt (hunt@redhat.com) wrote:
> > Did you try :
> >
> > - allocating the memory with kmalloc instead of vmalloc ?
>
> Why would I do that? What would I look for? vmalloc already works.
>
Memory allocated by vmalloc will generate a minor page fault when accessed from
kernel space on behalf of a different process. The page fault handler will
simply update the process'page table in that case. If the page fault handler is
instrumented for a minor fault and the logging code generates a page fault, it
clearly causes a double fault.
But as you only instrument sys_open, this case does not apply.
Mathieu
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