On Sun, Mar 21, 2010 at 07:43:00PM +0100, Ingo Molnar wrote:
If you want to access the guests file-system you need a piece of
software running in the guest which gives you this access. But when you
get an event this piece of software may not be runnable (if the guest is
in an interrupt handler or any other non-preemptible code path). When the
host finally gets access to the guests filesystem again the source of
that event may already be gone (process has exited, module unloaded...).
The only way to solve that is to pass the event information to the guest
immediatly and let it collect the information we want.
I am not talking about security. Security was sufficiently flamed about
already.
Same concern as above applies to call-chain generation too.
Avi was against that but I think it would make sense to give names to
virtual machines (with a default, similar to network interface names).
Then we can create a directory in /dev/ with that name (e.g.
/dev/vm/fedora/). Inside the guest a (priviledged) process can create
some kind of named virt-pipe which results in a device file created in
the guests directory (perf could create /dev/vm/fedora/perf for
example). This file is used for guest-host communication.
Thanks,
Joerg
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