[Qemu-devel] Understanding KVM

[Ian Molton]

Hi,

Im trying to figure out how (on, say, x86), qemu (1.3, git) knows when 
the guest has accessed a page - in particular, on a framebuffer.

It looks like its done via dirty page logs, which are maintained by the 
host kernel, so probably this is a kernel question, more than a qemu one.

Is this the case? if so, where do the bits in the dirty bitmap get set? 
I cant find anything in the kernel that seems to do much with it, other 
than to copy the bitmap to userspace.

-Ian