On Tue, Sep 04, 2018 at 04:00:31PM +0300, Denis Plotnikov wrote:
Hi Peter
Hi, Denis,
I moved the code to the repository
https://github.com/denis-plotnikov/qemu/tree/background-snapshot-kvm.
the current version includes fixes with respect to your comments for version
1.
I moved KVM related patches to the end of the branch (formerly patch
series).
Since, the KVM patches and the other parts to modify (vhost an others) are
needless in favor of upcoming userfaltfd,
I would ask you to review the general framework which is able to work with
tcg.
Thanks in advance!
Thank you for pushing the tree.
I might have made a mistake before that I thought this work is at
least working for TCG, but I think I was wrong. The problem is (I'm
trying to repeat Dave's question that you seems haven't yet answered):
even for TCG there could be use cases where the process might access
guest memory from the kernel space (e.g., vhost, or any system calls
that with a guest memory buffer passed in). I'm afraid mprotect() and
the whole signal-based mechanism cannot be able to address these page
faults, then we'll encounter adhoc errors and we'll need to fix all
these places up. Userfaultfd-wp should not have this problem.
I think the general idea of the work is good, but I'm not sure whether
we can merge the work if we don't settle these issues.
Regards,