| Message ID | 20230512080405.12043-1-yi-de.wu@mediatek.com |
|---|---|
| Headers | show |
| Series | GenieZone hypervisor drivers | expand |
On Fri, 12 May 2023 09:04:01 +0100, Yi-De Wu <yi-de.wu@mediatek.com> wrote: > > From: "Yingshiuan Pan" <yingshiuan.pan@mediatek.com> > > GenieZone is MediaTek hypervisor solution, and it is running in EL2 > stand alone as a type-I hypervisor. This patch exports a set of ioctl > interfaces for userspace VMM (e.g., crosvm) to operate guest VMs > lifecycle (creation and destroy) on GenieZone. > > Signed-off-by: Yingshiuan Pan <yingshiuan.pan@mediatek.com> > Signed-off-by: Yi-De Wu <yi-de.wu@mediatek.com> [...] > +/** > + * gzvm_gfn_to_pfn_memslot() - Translate gfn (guest ipa) to pfn (host pa), > + * result is in @pfn > + * > + * Leverage KVM's gfn_to_pfn_memslot(). Because gfn_to_pfn_memslot() needs > + * kvm_memory_slot as parameter, this function populates necessary fileds > + * for calling gfn_to_pfn_memslot(). > + * > + * Return: > + * * 0 - Succeed > + * * -EFAULT - Failed to convert > + */ > +static int gzvm_gfn_to_pfn_memslot(struct gzvm_memslot *memslot, u64 gfn, u64 *pfn) > +{ > + hfn_t __pfn; > + struct kvm_memory_slot kvm_slot = {0}; > + > + kvm_slot.base_gfn = memslot->base_gfn; > + kvm_slot.npages = memslot->npages; > + kvm_slot.dirty_bitmap = NULL; > + kvm_slot.userspace_addr = memslot->userspace_addr; > + kvm_slot.flags = memslot->flags; > + kvm_slot.id = memslot->slot_id; > + kvm_slot.as_id = 0; > + > + __pfn = gfn_to_pfn_memslot(&kvm_slot, gfn); > + if (is_error_noslot_pfn(__pfn)) { > + *pfn = 0; > + return -EFAULT; > + } I have commented on this before: there is absolutely *no way* that you can use KVM as the unwilling helper for your stuff. You are passing uninitialised data to the core KVM, completely ignoring the semantics of all the other fields. More importantly, you are now holding us responsible for any breakage that would be caused to your code if we change the internals of this *PRIVATE FUNCTION*. Do you see Xen or Hyper-V using KVM's internals as some sort of backend to make their life easier? No, because they understand that this is off-limits, and creates an unhealthy dependency for both hypervisors. So this is a strong NAK. And you can trust me to keep voicing my opposition to this sort of horror, wherever I will see these patches. M.