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KVM: arm64: Generalise kvm_pgtable_stage2_set_owner()

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kvm_pgtable_stage2_set_owner() can be generalised into a way to store
up to 59 bits in the page tables alongside a 4-bit 'type' identifier
specific to the format of the 59-bit payload.

Introduce kvm_pgtable_stage2_annotate() and move the existing invalid
ptes (for locked ptes and donated pages) over to the new scheme.

Tested-by: Fuad Tabba <tabba@google.com>
Tested-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://patch.msgid.link/20260330144841.26181-22-will@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
This commit is contained in:
Will Deacon
2026-03-30 15:48:22 +01:00
committed by Marc Zyngier
parent 664d616903
commit c6ba94640c
3 changed files with 62 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
arch/arm64/kvm/hyp/pgtable.c
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@@ -114,11 +114,6 @@ static kvm_pte_t kvm_init_valid_leaf_pte(u64 pa, kvm_pte_t attr, s8 level)
return pte;
}
static kvm_pte_t kvm_init_invalid_leaf_owner(u8 owner_id)
{
return FIELD_PREP(KVM_INVALID_PTE_OWNER_MASK, owner_id);
}
static int kvm_pgtable_visitor_cb(struct kvm_pgtable_walk_data *data,
const struct kvm_pgtable_visit_ctx *ctx,
enum kvm_pgtable_walk_flags visit)
@@ -581,7 +576,7 @@ void kvm_pgtable_hyp_destroy(struct kvm_pgtable *pgt)
struct stage2_map_data {
const u64 phys;
kvm_pte_t attr;
u8 owner_id;
kvm_pte_t pte_annot;
kvm_pte_t *anchor;
kvm_pte_t *childp;
@@ -798,7 +793,11 @@ static bool stage2_pte_is_counted(kvm_pte_t pte)
static bool stage2_pte_is_locked(kvm_pte_t pte)
{
return !kvm_pte_valid(pte) && (pte & KVM_INVALID_PTE_LOCKED);
if (kvm_pte_valid(pte))
return false;
return FIELD_GET(KVM_INVALID_PTE_TYPE_MASK, pte) ==
KVM_INVALID_PTE_TYPE_LOCKED;
}
static bool stage2_try_set_pte(const struct kvm_pgtable_visit_ctx *ctx, kvm_pte_t new)
@@ -829,6 +828,7 @@ static bool stage2_try_break_pte(const struct kvm_pgtable_visit_ctx *ctx,
struct kvm_s2_mmu *mmu)
{
struct kvm_pgtable_mm_ops *mm_ops = ctx->mm_ops;
kvm_pte_t locked_pte;
if (stage2_pte_is_locked(ctx->old)) {
/*
@@ -839,7 +839,9 @@ static bool stage2_try_break_pte(const struct kvm_pgtable_visit_ctx *ctx,
return false;
}
if (!stage2_try_set_pte(ctx, KVM_INVALID_PTE_LOCKED))
locked_pte = FIELD_PREP(KVM_INVALID_PTE_TYPE_MASK,
KVM_INVALID_PTE_TYPE_LOCKED);
if (!stage2_try_set_pte(ctx, locked_pte))
return false;
if (!kvm_pgtable_walk_skip_bbm_tlbi(ctx)) {
@@ -964,7 +966,7 @@ static int stage2_map_walker_try_leaf(const struct kvm_pgtable_visit_ctx *ctx,
if (!data->annotation)
new = kvm_init_valid_leaf_pte(phys, data->attr, ctx->level);
else
new = kvm_init_invalid_leaf_owner(data->owner_id);
new = data->pte_annot;
/*
* Skip updating the PTE if we are trying to recreate the exact
@@ -1118,16 +1120,18 @@ int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size,
return ret;
}
int kvm_pgtable_stage2_set_owner(struct kvm_pgtable *pgt, u64 addr, u64 size,
void *mc, u8 owner_id)
int kvm_pgtable_stage2_annotate(struct kvm_pgtable *pgt, u64 addr, u64 size,
void *mc, enum kvm_invalid_pte_type type,
kvm_pte_t pte_annot)
{
int ret;
struct stage2_map_data map_data = {
.mmu = pgt->mmu,
.memcache = mc,
.owner_id = owner_id,
.force_pte = true,
.annotation = true,
.pte_annot = pte_annot |
FIELD_PREP(KVM_INVALID_PTE_TYPE_MASK, type),
};
struct kvm_pgtable_walker walker = {
.cb = stage2_map_walker,
@@ -1136,7 +1140,10 @@ int kvm_pgtable_stage2_set_owner(struct kvm_pgtable *pgt, u64 addr, u64 size,
.arg = &map_data,
};
if (owner_id > KVM_MAX_OWNER_ID)
if (pte_annot & ~KVM_INVALID_PTE_ANNOT_MASK)
return -EINVAL;
if (!type || type == KVM_INVALID_PTE_TYPE_LOCKED)
return -EINVAL;
ret = kvm_pgtable_walk(pgt, addr, size, &walker);