[Qemu-devel] Tracing guest memory accesses

[Diwaker Gupta]

Hi list,

I've searched the archives and the forums, but couldn't get a specific
solution (I think my search terms might have been too general).
Anyways, I think what I'm trying to do should be relatively easy and
hopefully experts here will be able to quickly point me in the right
direction :)

So I'm just trying to trace all the memory accesses (virtual
addresses) by the guest. I need to trace both reads and writes. If I
can get the exact address, thats great. Otherwise I'm happy with
simply logging the relevant page.

I've uncommented DEBUG_IOMMU in hw/iommu.c and I've added some debug
statements to the io_read and io_write calls in softmmu_template.h. At
this point I have two questions:

o do these changes seem correct? As in, do they actually track the
read/write memory accesses done by the guest? I was concerned because
when I start a guest, I see a whole lot of writes and not as many
reads, which seems a little counter intuitive.

o are these changes complete? As in, are there other entry/exit points
in the code for memory accesses that I'm missing.

Thanks,
Diwaker
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