shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-06 10:58:48 +09:00
Code Issues Packages Projects Releases Wiki Activity

ANDROID: BACKPORT: KVM: arm64: Use guest VMID as owner id

Browse Source 
We currently track page-ownership in nVHE protected mode with a rather
coarse granularity -- all guests share a unique owner id. But a finer
grain tracking will be useful soon, to e.g. handle host stage-2 faults
caused by an access to guest memory. To prepare the ground for this,
let's use the guest VMIDs as owner ids, hence allowing to distinguish
between all of them. This only works since the pKVM EL2 hypervisor
guarantees the stability of the VMIDs for the entire lifetime of a guest
VM. This will need some rework when/if we attempt to run more than 255
guests concurrently in protected mode as we'll have to handle VMID
rollovers, but there is no clear need for now, so let's keep it simple
to start.

Signed-off-by: Quentin Perret <qperret@google.com>
[willdeacon@: Update constants in mem_protect.h]
Bug: 209580772
Change-Id: I5c5c8061617d7dc481ae5e25a0391b306aabbd8c
Signed-off-by: Will Deacon <willdeacon@google.com>
This commit is contained in:
Quentin Perret
2021-10-26 12:07:14 +01:00
committed by Will Deacon
parent 5da4a4ca5f
commit dded44bcfd
2 changed files with 9 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
View File

@@ -53,8 +53,7 @@ extern struct host_kvm host_kvm;
typedef u32 pkvm_id;
static const pkvm_id pkvm_host_id = 0;
static const pkvm_id pkvm_hyp_id = 1;
static const pkvm_id pkvm_guest_id = 2;
static const pkvm_id pkvm_hyp_id = (1 << 16);
extern unsigned long hyp_nr_cpus;

8
arch/arm64/kvm/hyp/nvhe/mem_protect.c
View File

@@ -29,6 +29,12 @@ struct host_kvm host_kvm;
static struct hyp_pool host_s2_pool;
static pkvm_id pkvm_guest_id(struct kvm_vcpu *vcpu)
{
return vcpu->arch.hw_mmu->vmid.vmid;
}
static DEFINE_PER_CPU(struct kvm_shadow_vm *, __current_vm);
#define current_vm (*this_cpu_ptr(&__current_vm))
@@ -687,6 +693,8 @@ static pkvm_id completer_owner_id(const struct pkvm_mem_transition *tx)
return pkvm_host_id;
case PKVM_ID_HYP:
return pkvm_hyp_id;
case PKVM_ID_GUEST:
return pkvm_guest_id(tx->completer.guest.vcpu);
default:
WARN_ON(1);
return -1;