On 05.08.20 19:41, Stefano Stabellini wrote:
Hi Stefano
On Wed, 5 Aug 2020, Jan Beulich wrote:
On 05.08.2020 01:22, Stefano Stabellini wrote:
On Mon, 3 Aug 2020, Oleksandr Tyshchenko wrote:
--- a/xen/include/asm-arm/p2m.h
+++ b/xen/include/asm-arm/p2m.h
@@ -385,10 +385,11 @@ static inline int set_foreign_p2m_entry(struct domain *d,
unsigned long gfn,
mfn_t mfn)
{
/*
- * NOTE: If this is implemented then proper reference counting of
- * foreign entries will need to be implemented.
+ * XXX: handle properly reference. It looks like the page may not always
+ * belong to d.
Just as a reference, and without taking away anything from the comment,
I think that QEMU is doing its own internal reference counting for these
mappings.
Which of course in no way replaces the need to do proper ref counting
in Xen. (Just FAOD, as I'm not sure why you've said what you've said.)
Given the state of the series, which is a RFC, I only meant to say that
the lack of refcounting shouldn't prevent things from working when using
QEMU. In the sense that if somebody wants to give it a try for an early
demo, they should be able to see it running without crashes.
Yes, for the early demo it works fine, however I don't use Qemu.
Of course, refcounting needs to be implemented.
+
--
Regards,
Oleksandr Tyshchenko
