[PATCH v2 09/22] KVM: arm64: Add a range to __pkvm_host_reclaim_guest()
Vincent Donnefort
vdonnefort at google.com
Fri Sep 11 06:50:40 PDT 2026
In preparation for supporting stage-2 huge mappings for protected VMs,
add a nr_pages argument to the __pkvm_host_reclaim_guest() hypercall.
This range supports only two values: 1 or PMD_SIZE / PAGE_SIZE (that is
512 on a 4K-pages system).
Also, rename both the mem_protect function and the HVC to
__pkvm_host_reclaim_guest() as it can now operate on a range.
Signed-off-by: Vincent Donnefort <vdonnefort at google.com>
---
arch/arm64/include/asm/kvm_asm.h | 2 +-
arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 2 +-
arch/arm64/kvm/hyp/include/nvhe/pkvm.h | 2 +-
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 7 ++-
arch/arm64/kvm/hyp/nvhe/mem_protect.c | 58 +++++++++++--------
arch/arm64/kvm/hyp/nvhe/pkvm.c | 4 +-
arch/arm64/kvm/pkvm.c | 5 +-
7 files changed, 47 insertions(+), 33 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 7fdec5d98201..95dd62e5601b 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -109,7 +109,7 @@ enum __kvm_host_smccc_func {
__KVM_HOST_SMCCC_FUNC___pkvm_init_vcpu,
__KVM_HOST_SMCCC_FUNC___pkvm_vcpu_in_poison_fault,
__KVM_HOST_SMCCC_FUNC___pkvm_force_reclaim_guest_page,
- __KVM_HOST_SMCCC_FUNC___pkvm_reclaim_dying_guest_page,
+ __KVM_HOST_SMCCC_FUNC___pkvm_reclaim_dying_guest,
__KVM_HOST_SMCCC_FUNC___pkvm_start_teardown_vm,
__KVM_HOST_SMCCC_FUNC___pkvm_finalize_teardown_vm,
__KVM_HOST_SMCCC_FUNC___pkvm_vcpu_load,
diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
index c13f258fffb7..646d2335e5c1 100644
--- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
+++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
@@ -42,7 +42,7 @@ int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages);
int __pkvm_host_donate_guest(u64 pfn, u64 gfn, u64 nr_pages, struct pkvm_hyp_vcpu *vcpu);
int __pkvm_vcpu_in_poison_fault(struct pkvm_hyp_vcpu *hyp_vcpu);
int __pkvm_host_force_reclaim_page_guest(phys_addr_t phys);
-int __pkvm_host_reclaim_page_guest(u64 gfn, struct pkvm_hyp_vm *vm);
+int __pkvm_host_reclaim_guest(u64 gfn, u64 nr_pages, struct pkvm_hyp_vm *vm);
int __pkvm_host_share_guest(u64 pfn, u64 gfn, u64 nr_pages, struct pkvm_hyp_vcpu *vcpu,
enum kvm_pgtable_prot prot);
int __pkvm_host_unshare_guest(u64 gfn, u64 nr_pages, struct pkvm_hyp_vm *hyp_vm);
diff --git a/arch/arm64/kvm/hyp/include/nvhe/pkvm.h b/arch/arm64/kvm/hyp/include/nvhe/pkvm.h
index f04cea5ff389..4183614055bc 100644
--- a/arch/arm64/kvm/hyp/include/nvhe/pkvm.h
+++ b/arch/arm64/kvm/hyp/include/nvhe/pkvm.h
@@ -74,7 +74,7 @@ int __pkvm_init_vm(struct kvm *host_kvm, unsigned long vm_hva,
int __pkvm_init_vcpu(pkvm_handle_t handle, struct kvm_vcpu *host_vcpu,
unsigned long vcpu_hva);
-int __pkvm_reclaim_dying_guest_page(pkvm_handle_t handle, u64 gfn);
+int __pkvm_reclaim_dying_guest(pkvm_handle_t handle, u64 gfn, u64 nr_pages);
int __pkvm_start_teardown_vm(pkvm_handle_t handle);
int __pkvm_finalize_teardown_vm(pkvm_handle_t handle);
diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
index 84ff87d4e18d..ce816f01ab4f 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
@@ -814,12 +814,13 @@ static void handle___pkvm_force_reclaim_guest_page(struct kvm_cpu_context *host_
cpu_reg(host_ctxt, 1) = __pkvm_host_force_reclaim_page_guest(phys);
}
-static void handle___pkvm_reclaim_dying_guest_page(struct kvm_cpu_context *host_ctxt)
+static void handle___pkvm_reclaim_dying_guest(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
DECLARE_REG(u64, gfn, host_ctxt, 2);
+ DECLARE_REG(u64, nr_pages, host_ctxt, 3);
- cpu_reg(host_ctxt, 1) = __pkvm_reclaim_dying_guest_page(handle, gfn);
+ cpu_reg(host_ctxt, 1) = __pkvm_reclaim_dying_guest(handle, gfn, nr_pages);
}
static void handle___pkvm_start_teardown_vm(struct kvm_cpu_context *host_ctxt)
@@ -961,7 +962,7 @@ static const hcall_t host_hcall[] = {
HANDLE_FUNC(__pkvm_init_vcpu),
HANDLE_FUNC(__pkvm_vcpu_in_poison_fault),
HANDLE_FUNC(__pkvm_force_reclaim_guest_page),
- HANDLE_FUNC(__pkvm_reclaim_dying_guest_page),
+ HANDLE_FUNC(__pkvm_reclaim_dying_guest),
HANDLE_FUNC(__pkvm_start_teardown_vm),
HANDLE_FUNC(__pkvm_finalize_teardown_vm),
HANDLE_FUNC(__pkvm_vcpu_load),
diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
index 642096b2e711..25a86b318dfc 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
@@ -898,7 +898,8 @@ static int __guest_check_page_state_range(struct pkvm_hyp_vm *vm, u64 addr,
return check_page_state_range(&vm->pgt, addr, size, &d);
}
-static int get_valid_guest_pte(struct pkvm_hyp_vm *vm, u64 ipa, kvm_pte_t *ptep, u64 *physp)
+static int __get_valid_guest_pte(struct pkvm_hyp_vm *vm, u64 ipa,
+ kvm_pte_t *ptep, u64 *physp, s8 *levelp)
{
kvm_pte_t pte;
u64 phys;
@@ -912,20 +913,32 @@ static int get_valid_guest_pte(struct pkvm_hyp_vm *vm, u64 ipa, kvm_pte_t *ptep,
return -EHWPOISON;
if (!kvm_pte_valid(pte))
return -ENOENT;
- if (level != KVM_PGTABLE_LAST_LEVEL)
- return -E2BIG;
phys = kvm_pte_to_phys(pte);
- ret = check_range_allowed_memory(phys, phys + PAGE_SIZE);
+ ret = check_range_allowed_memory(phys, phys + kvm_granule_size(level));
if (WARN_ON(ret))
return ret;
*ptep = pte;
*physp = phys;
+ *levelp = level;
return 0;
}
+static int get_valid_guest_pte(struct pkvm_hyp_vm *vm, u64 ipa, u64 size,
+ kvm_pte_t *ptep, u64 *physp)
+{
+ s8 level;
+ int ret;
+
+ ret = __get_valid_guest_pte(vm, ipa, ptep, physp, &level);
+ if (ret)
+ return ret;
+
+ return kvm_granule_size(level) == size ? 0 : -E2BIG;
+}
+
int __pkvm_vcpu_in_poison_fault(struct pkvm_hyp_vcpu *hyp_vcpu)
{
struct pkvm_hyp_vm *vm = pkvm_hyp_vcpu_to_hyp_vm(hyp_vcpu);
@@ -1008,7 +1021,7 @@ int __pkvm_guest_share_host(struct pkvm_hyp_vcpu *vcpu, u64 gfn)
host_lock_component();
guest_lock_component(vm);
- ret = get_valid_guest_pte(vm, ipa, &pte, &phys);
+ ret = get_valid_guest_pte(vm, ipa, PAGE_SIZE, &pte, &phys);
if (ret)
goto unlock;
@@ -1040,7 +1053,7 @@ int __pkvm_guest_unshare_host(struct pkvm_hyp_vcpu *vcpu, u64 gfn)
host_lock_component();
guest_lock_component(vm);
- ret = get_valid_guest_pte(vm, ipa, &pte, &phys);
+ ret = get_valid_guest_pte(vm, ipa, PAGE_SIZE, &pte, &phys);
if (ret)
goto unlock;
@@ -1346,7 +1359,7 @@ int __pkvm_host_force_reclaim_page_guest(phys_addr_t phys)
ipa = hyp_pfn_to_phys(gfn);
guest_lock_component(vm);
- ret = get_valid_guest_pte(vm, ipa, &pte, &pa);
+ ret = get_valid_guest_pte(vm, ipa, PAGE_SIZE, &pte, &pa);
if (ret)
goto unlock_guest;
@@ -1374,35 +1387,40 @@ int __pkvm_host_force_reclaim_page_guest(phys_addr_t phys)
return ret;
}
-int __pkvm_host_reclaim_page_guest(u64 gfn, struct pkvm_hyp_vm *vm)
+int __pkvm_host_reclaim_guest(u64 gfn, u64 nr_pages, struct pkvm_hyp_vm *vm)
{
u64 ipa = hyp_pfn_to_phys(gfn);
kvm_pte_t pte;
u64 phys;
+ u64 size;
int ret;
+ ret = __guest_check_transition_size(0, ipa, nr_pages, &size);
+ if (ret)
+ return ret;
+
host_lock_component();
guest_lock_component(vm);
- ret = get_valid_guest_pte(vm, ipa, &pte, &phys);
+ ret = get_valid_guest_pte(vm, ipa, size, &pte, &phys);
if (ret)
goto unlock;
switch (guest_get_page_state(pte, ipa)) {
case PKVM_PAGE_OWNED:
- WARN_ON(__host_check_page_state_range(phys, PAGE_SIZE, PKVM_NOPAGE));
- hyp_poison_range(phys, PAGE_SIZE);
+ WARN_ON(__host_check_page_state_range(phys, size, PKVM_NOPAGE));
+ hyp_poison_range(phys, size);
break;
case PKVM_PAGE_SHARED_OWNED:
- WARN_ON(__host_check_page_state_range(phys, PAGE_SIZE, PKVM_PAGE_SHARED_BORROWED));
+ WARN_ON(__host_check_page_state_range(phys, size, PKVM_PAGE_SHARED_BORROWED));
break;
default:
ret = -EPERM;
goto unlock;
}
- WARN_ON(kvm_pgtable_stage2_unmap(&vm->pgt, ipa, PAGE_SIZE));
- WARN_ON(host_stage2_set_owner_locked(phys, PAGE_SIZE, PKVM_ID_HOST));
+ WARN_ON(kvm_pgtable_stage2_unmap(&vm->pgt, ipa, size));
+ WARN_ON(host_stage2_set_owner_locked(phys, size, PKVM_ID_HOST));
unlock:
guest_unlock_component(vm);
@@ -1555,11 +1573,10 @@ static int __check_host_shared_guest(struct pkvm_hyp_vm *vm, u64 *__phys, u64 ip
s8 level;
int ret;
- ret = kvm_pgtable_get_leaf(&vm->pgt, ipa, &pte, &level);
+ ret = __get_valid_guest_pte(vm, ipa, &pte, &phys, &level);
if (ret)
return ret;
- if (!kvm_pte_valid(pte))
- return -ENOENT;
+
if (size && kvm_granule_size(level) != size)
return -E2BIG;
@@ -1570,11 +1587,6 @@ static int __check_host_shared_guest(struct pkvm_hyp_vm *vm, u64 *__phys, u64 ip
if (state != PKVM_PAGE_SHARED_BORROWED)
return -EPERM;
- phys = kvm_pte_to_phys(pte);
- ret = check_range_allowed_memory(phys, phys + size);
- if (WARN_ON(ret))
- return ret;
-
for_each_hyp_page(page, phys, size) {
if (get_host_state(page) != PKVM_PAGE_SHARED_OWNED)
return -EPERM;
@@ -1946,7 +1958,7 @@ int __pkvm_ownership_selftest(u64 pfn, u64 pgtable_pfn, unsigned long pgtable_nr
selftest_state.host = PKVM_PAGE_OWNED;
selftest_state.guest[1] = PKVM_NOPAGE;
- assert_transition_res(0, __pkvm_host_reclaim_page_guest, gfn + 1, vm);
+ assert_transition_res(0, __pkvm_host_reclaim_guest, gfn + 1, 1, vm);
assert_transition_res(-EPERM, __pkvm_host_donate_guest, pfn, gfn, 1, vcpu);
assert_transition_res(-EPERM, __pkvm_host_share_guest, pfn, gfn, 1, vcpu, prot);
diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c
index ad9afe2cd1b9..6590c4de7fd2 100644
--- a/arch/arm64/kvm/hyp/nvhe/pkvm.c
+++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c
@@ -965,7 +965,7 @@ teardown_donated_memory(struct kvm_hyp_memcache *mc, void *addr, size_t size)
unmap_donated_memory_noclear(addr, size);
}
-int __pkvm_reclaim_dying_guest_page(pkvm_handle_t handle, u64 gfn)
+int __pkvm_reclaim_dying_guest(pkvm_handle_t handle, u64 gfn, u64 nr_pages)
{
struct pkvm_hyp_vm *hyp_vm = get_pkvm_hyp_vm(handle);
int ret = -EINVAL;
@@ -974,7 +974,7 @@ int __pkvm_reclaim_dying_guest_page(pkvm_handle_t handle, u64 gfn)
return ret;
if (hyp_vm->kvm.arch.pkvm.is_dying)
- ret = __pkvm_host_reclaim_page_guest(gfn, hyp_vm);
+ ret = __pkvm_host_reclaim_guest(gfn, nr_pages, hyp_vm);
put_pkvm_hyp_vm(hyp_vm);
return ret;
diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c
index 99100204b093..5b4256b19507 100644
--- a/arch/arm64/kvm/pkvm.c
+++ b/arch/arm64/kvm/pkvm.c
@@ -369,8 +369,9 @@ static int __pkvm_pgtable_stage2_reclaim(struct kvm_pgtable *pgt, u64 start, u64
for_each_mapping_in_range_safe(pgt, start, end, mapping) {
struct page *page;
- ret = kvm_call_hyp_nvhe(__pkvm_reclaim_dying_guest_page,
- handle, mapping->gfn);
+ ret = kvm_call_hyp_nvhe(__pkvm_reclaim_dying_guest,
+ handle, mapping->gfn,
+ (u64)mapping->nr_pages);
if (WARN_ON(ret))
continue;
--
2.55.0.1007.g17ff1f9808-goog
More information about the linux-arm-kernel
mailing list