From: Quentin Perret <qper...@google.com>
We currently fixup the hypervisor stage-1 refcount only for specific
portions of the hyp stage-1 VA space. In order to allow unmapping pages
outside of these ranges, let's fixup the refcount for the entire hyp VA
space.
Signed-off-by: Quentin Perret <qper...@google.com>
---
arch/arm64/kvm/hyp/nvhe/setup.c | 62 +++++++++++++++++++++++----------
1 file changed, 43 insertions(+), 19 deletions(-)
diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c
index e9e146e50254..b306da2b5dae 100644
--- a/arch/arm64/kvm/hyp/nvhe/setup.c
+++ b/arch/arm64/kvm/hyp/nvhe/setup.c
@@ -167,12 +167,11 @@ static void hpool_put_page(void *addr)
hyp_put_page(&hpool, addr);
}
-static int finalize_host_mappings_walker(u64 addr, u64 end, u32 level,
- kvm_pte_t *ptep,
- enum kvm_pgtable_walk_flags flag,
- void * const arg)
+static int fix_host_ownership_walker(u64 addr, u64 end, u32 level,
+ kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag,
+ void * const arg)
{
- struct kvm_pgtable_mm_ops *mm_ops = arg;
enum kvm_pgtable_prot prot;
enum pkvm_page_state state;
kvm_pte_t pte = *ptep;
@@ -181,15 +180,6 @@ static int finalize_host_mappings_walker(u64 addr, u64
end, u32 level,
if (!kvm_pte_valid(pte))
return 0;
- /*
- * Fix-up the refcount for the page-table pages as the early allocator
- * was unable to access the hyp_vmemmap and so the buddy allocator has
- * initialised the refcount to '1'.
- */
- mm_ops->get_page(ptep);
- if (flag != KVM_PGTABLE_WALK_LEAF)
- return 0;
-
if (level != (KVM_PGTABLE_MAX_LEVELS - 1))
return -EINVAL;
@@ -218,12 +208,30 @@ static int finalize_host_mappings_walker(u64 addr, u64
end, u32 level,
return host_stage2_idmap_locked(phys, PAGE_SIZE, prot);
}
-static int finalize_host_mappings(void)
+static int fix_hyp_pgtable_refcnt_walker(u64 addr, u64 end, u32 level,
+ kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag,
+ void * const arg)
+{
+ struct kvm_pgtable_mm_ops *mm_ops = arg;
+ kvm_pte_t pte = *ptep;
+
+ /*
+ * Fix-up the refcount for the page-table pages as the early allocator
+ * was unable to access the hyp_vmemmap and so the buddy allocator has
+ * initialised the refcount to '1'.
+ */
+ if (kvm_pte_valid(pte))
+ mm_ops->get_page(ptep);
+
+ return 0;
+}
+
+static int fix_host_ownership(void)
{
struct kvm_pgtable_walker walker = {
- .cb = finalize_host_mappings_walker,
- .flags = KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST,
- .arg = pkvm_pgtable.mm_ops,
+ .cb = fix_host_ownership_walker,
+ .flags = KVM_PGTABLE_WALK_LEAF,
};
int i, ret;
@@ -239,6 +247,18 @@ static int finalize_host_mappings(void)
return 0;
}
+static int fix_hyp_pgtable_refcnt(void)
+{
+ struct kvm_pgtable_walker walker = {
+ .cb = fix_hyp_pgtable_refcnt_walker,
+ .flags = KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST,
+ .arg = pkvm_pgtable.mm_ops,
+ };
+
+ return kvm_pgtable_walk(&pkvm_pgtable, 0, BIT(pkvm_pgtable.ia_bits),
+ &walker);
+}
+
void __noreturn __pkvm_init_finalise(void)
{
struct kvm_host_data *host_data = this_cpu_ptr(&kvm_host_data);
@@ -268,7 +288,11 @@ void __noreturn __pkvm_init_finalise(void)
};
pkvm_pgtable.mm_ops = &pkvm_pgtable_mm_ops;
- ret = finalize_host_mappings();
+ ret = fix_host_ownership();
+ if (ret)
+ goto out;
+
+ ret = fix_hyp_pgtable_refcnt();
if (ret)
goto out;
--
2.36.1.124.g0e6072fb45-goog
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