diff options
| author | Quentin Perret <qperret@google.com> | 2021-12-15 16:12:20 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-12-16 12:58:56 +0000 |
| commit | d6b4bd3f4897f3b60ac9e8c9e2f0300e739b3392 (patch) | |
| tree | cb99d8b0d527f39e4b366f243b2b626527a96808 /arch | |
| parent | 2ea2ff91e82293909d4879b0b4c6c94b02d52b7e (diff) | |
| download | linux-d6b4bd3f4897f3b60ac9e8c9e2f0300e739b3392.tar.bz2 | |
KVM: arm64: Fixup hyp stage-1 refcount
In nVHE-protected mode, the hyp stage-1 page-table refcount is broken
due to the lack of refcount support in the early allocator. Fix-up the
refcount in the finalize walker, once the 'hyp_vmemmap' is up and running.
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211215161232.1480836-4-qperret@google.com
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/setup.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c index 578f71798c2e..875b5174342f 100644 --- a/arch/arm64/kvm/hyp/nvhe/setup.c +++ b/arch/arm64/kvm/hyp/nvhe/setup.c @@ -165,6 +165,7 @@ static int finalize_host_mappings_walker(u64 addr, u64 end, u32 level, 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; @@ -173,6 +174,15 @@ 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; @@ -205,7 +215,8 @@ static int finalize_host_mappings(void) { struct kvm_pgtable_walker walker = { .cb = finalize_host_mappings_walker, - .flags = KVM_PGTABLE_WALK_LEAF, + .flags = KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST, + .arg = pkvm_pgtable.mm_ops, }; int i, ret; @@ -240,10 +251,6 @@ void __noreturn __pkvm_init_finalise(void) if (ret) goto out; - ret = finalize_host_mappings(); - if (ret) - goto out; - pkvm_pgtable_mm_ops = (struct kvm_pgtable_mm_ops) { .zalloc_page = hyp_zalloc_hyp_page, .phys_to_virt = hyp_phys_to_virt, @@ -253,6 +260,10 @@ void __noreturn __pkvm_init_finalise(void) }; pkvm_pgtable.mm_ops = &pkvm_pgtable_mm_ops; + ret = finalize_host_mappings(); + if (ret) + goto out; + out: /* * We tail-called to here from handle___pkvm_init() and will not return, |