Hi Marc,
On 25-11-2021 07:19 pm, Marc Zyngier wrote:
[+ Quentin]
Hi Ganapatro,
On Mon, 22 Nov 2021 09:58:02 +0000,
Ganapatrao Kulkarni <gankulkarni@xxxxxxxxxxxxxxxxxxxxxx> wrote:
The kvm_pgtable_stage2_init/kvm_pgtable_stage2_init_flags function
assume arch->mmu is same across all stage 2 mmu and initializes
the pgt(page table) using arch->mmu.
Using armc->mmu is not appropriate when nested virtualization is enabled
since there are multiple stage 2 mmu tables are initialized to manage
Guest-Hypervisor as well as Nested VM for the same vCPU.
Add a mmu argument to kvm_pgtable_stage2_init that can be used during
initialization. This patch is a preparatory patch for the
nested virtualization series and no functional changes.
Thanks for having had a look, and for the analysis. This is obviously
a result of a hasty conversion to the 'new' page table code, and a
total oversight on my part.
I'm however not particularly thrilled with the approach you have taken
though, as carrying both the kvm->arch pointer *and* the mmu pointer
seems totally redundant (the mmu structure already has a backpointer
to kvm->arch or its pkvm equivalent). All we need is to rework the
initialisation for this pointer to be correct at the point of where we
follow it first.
I've pushed out my own version of this[1]. Please have a look.
Thanks,
M.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/commit/?h=kvm-arm64/nv-5.16-WIP&id=21790a24d88c3ed37989533709dad3d40905f5c3
Thanks for the rework and rebasing to 5.16.
I went through the patch, the gist of the patch seems to me same.
Please free feel to add,
Reviewed-by: Ganapatrao Kulkarni <gankulkarni@xxxxxxxxxxxxxxxxxxxxxx>
Looks like kvm-arm64/nv-5.16-WIP branch is broken for NV.
I tried booting Guest hypervisor using lkvm and the vcpu init from lkvm
is failing(Fatal: Unable to initialise vcpu). Did not dig/debug more in
to the issue yet.
Thanks,
Ganapat
