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Re: double fault
* Martin Hunt (hunt@redhat.com) wrote:
> Changing the kprobe to other functions does not always trigger the bug.
>
> The problem also has something to do with the size of the context array.
> Changing NR_CPUS to 128 (which makes the array really huge) was enough
> to cause the double fault to happen on all my RHEL machines (including
> x86_64) except for ones running under vmware. I changed the code to use
> vmalloc (we really want vmalloc_node() but RHEL4 doesn't have it) and
> all the crashes stopped on every machine.
>
What are the flags used for the memory allocated by vmalloc ?
Did you try :
- allocating the memory with kmalloc instead of vmalloc ?
- to see if there is a code path that goes from do_page_fault to sys_open ? I
would be surprised about it, but we never know...
Mathieu
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