Hi Drew,
On 2020/3/30 17:11, Andrew Jones wrote:
On Mon, Mar 30, 2020 at 10:46:57AM +0200, Auger Eric wrote:
Hi Zenghui,
On 3/30/20 10:30 AM, Zenghui Yu wrote:
[...]
Otherwise I think we will end-up with memory corruption when writing
the command queue. But it seems that everything just works fine ...
So I'm really confused here :-/
I was told by Paolo that the VA/PA memory map is flat in kvmunit test.
What does flat mean? kvm-unit-tests, at least arm/arm64, does prepare
an identity map of all physical memory, which explains why the above
is working. It's doing virt_to_phys(some-virt-addr), which gets a
phys addr, but when the ITS uses it as a virt addr it works because
we *also* have a virt addr == phys addr mapping in the default page
table, which is named "idmap" for good reason.
Thanks for the explanation :-). I will have a look at the arm/arm64 mm
code to learn it.
Thanks,
Zenghui
