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Diffstat (limited to 'arch/arm64/kvm/mmu.c')
-rw-r--r--arch/arm64/kvm/mmu.c195
1 files changed, 133 insertions, 62 deletions
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 60ee3d9f01f8..31d7fa4c7c14 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -128,6 +128,25 @@ static void kvm_s2_free_pages_exact(void *virt, size_t size)
free_pages_exact(virt, size);
}
+static struct kvm_pgtable_mm_ops kvm_s2_mm_ops;
+
+static void stage2_free_removed_table_rcu_cb(struct rcu_head *head)
+{
+ struct page *page = container_of(head, struct page, rcu_head);
+ void *pgtable = page_to_virt(page);
+ u32 level = page_private(page);
+
+ kvm_pgtable_stage2_free_removed(&kvm_s2_mm_ops, pgtable, level);
+}
+
+static void stage2_free_removed_table(void *addr, u32 level)
+{
+ struct page *page = virt_to_page(addr);
+
+ set_page_private(page, (unsigned long)level);
+ call_rcu(&page->rcu_head, stage2_free_removed_table_rcu_cb);
+}
+
static void kvm_host_get_page(void *addr)
{
get_page(virt_to_page(addr));
@@ -640,8 +659,8 @@ static struct kvm_pgtable_mm_ops kvm_user_mm_ops = {
static int get_user_mapping_size(struct kvm *kvm, u64 addr)
{
struct kvm_pgtable pgt = {
- .pgd = (kvm_pte_t *)kvm->mm->pgd,
- .ia_bits = VA_BITS,
+ .pgd = (kvm_pteref_t)kvm->mm->pgd,
+ .ia_bits = vabits_actual,
.start_level = (KVM_PGTABLE_MAX_LEVELS -
CONFIG_PGTABLE_LEVELS),
.mm_ops = &kvm_user_mm_ops,
@@ -662,6 +681,7 @@ static struct kvm_pgtable_mm_ops kvm_s2_mm_ops = {
.zalloc_page = stage2_memcache_zalloc_page,
.zalloc_pages_exact = kvm_s2_zalloc_pages_exact,
.free_pages_exact = kvm_s2_free_pages_exact,
+ .free_removed_table = stage2_free_removed_table,
.get_page = kvm_host_get_page,
.put_page = kvm_s2_put_page,
.page_count = kvm_host_page_count,
@@ -675,15 +695,42 @@ static struct kvm_pgtable_mm_ops kvm_s2_mm_ops = {
* kvm_init_stage2_mmu - Initialise a S2 MMU structure
* @kvm: The pointer to the KVM structure
* @mmu: The pointer to the s2 MMU structure
+ * @type: The machine type of the virtual machine
*
* Allocates only the stage-2 HW PGD level table(s).
* Note we don't need locking here as this is only called when the VM is
* created, which can only be done once.
*/
-int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu)
+int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu, unsigned long type)
{
+ u32 kvm_ipa_limit = get_kvm_ipa_limit();
int cpu, err;
struct kvm_pgtable *pgt;
+ u64 mmfr0, mmfr1;
+ u32 phys_shift;
+
+ if (type & ~KVM_VM_TYPE_ARM_IPA_SIZE_MASK)
+ return -EINVAL;
+
+ phys_shift = KVM_VM_TYPE_ARM_IPA_SIZE(type);
+ if (is_protected_kvm_enabled()) {
+ phys_shift = kvm_ipa_limit;
+ } else if (phys_shift) {
+ if (phys_shift > kvm_ipa_limit ||
+ phys_shift < ARM64_MIN_PARANGE_BITS)
+ return -EINVAL;
+ } else {
+ phys_shift = KVM_PHYS_SHIFT;
+ if (phys_shift > kvm_ipa_limit) {
+ pr_warn_once("%s using unsupported default IPA limit, upgrade your VMM\n",
+ current->comm);
+ return -EINVAL;
+ }
+ }
+
+ mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+ mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
+ kvm->arch.vtcr = kvm_get_vtcr(mmfr0, mmfr1, phys_shift);
if (mmu->pgt != NULL) {
kvm_err("kvm_arch already initialized?\n");
@@ -807,6 +854,32 @@ void kvm_free_stage2_pgd(struct kvm_s2_mmu *mmu)
}
}
+static void hyp_mc_free_fn(void *addr, void *unused)
+{
+ free_page((unsigned long)addr);
+}
+
+static void *hyp_mc_alloc_fn(void *unused)
+{
+ return (void *)__get_free_page(GFP_KERNEL_ACCOUNT);
+}
+
+void free_hyp_memcache(struct kvm_hyp_memcache *mc)
+{
+ if (is_protected_kvm_enabled())
+ __free_hyp_memcache(mc, hyp_mc_free_fn,
+ kvm_host_va, NULL);
+}
+
+int topup_hyp_memcache(struct kvm_hyp_memcache *mc, unsigned long min_pages)
+{
+ if (!is_protected_kvm_enabled())
+ return 0;
+
+ return __topup_hyp_memcache(mc, min_pages, hyp_mc_alloc_fn,
+ kvm_host_pa, NULL);
+}
+
/**
* kvm_phys_addr_ioremap - map a device range to guest IPA
*
@@ -841,7 +914,7 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
write_lock(&kvm->mmu_lock);
ret = kvm_pgtable_stage2_map(pgt, addr, PAGE_SIZE, pa, prot,
- &cache);
+ &cache, 0);
write_unlock(&kvm->mmu_lock);
if (ret)
break;
@@ -1091,32 +1164,26 @@ static int get_vma_page_shift(struct vm_area_struct *vma, unsigned long hva)
* - mmap_lock protects between a VM faulting a page in and the VMM performing
* an mprotect() to add VM_MTE
*/
-static int sanitise_mte_tags(struct kvm *kvm, kvm_pfn_t pfn,
- unsigned long size)
+static void sanitise_mte_tags(struct kvm *kvm, kvm_pfn_t pfn,
+ unsigned long size)
{
unsigned long i, nr_pages = size >> PAGE_SHIFT;
- struct page *page;
+ struct page *page = pfn_to_page(pfn);
if (!kvm_has_mte(kvm))
- return 0;
-
- /*
- * pfn_to_online_page() is used to reject ZONE_DEVICE pages
- * that may not support tags.
- */
- page = pfn_to_online_page(pfn);
-
- if (!page)
- return -EFAULT;
+ return;
for (i = 0; i < nr_pages; i++, page++) {
- if (!test_bit(PG_mte_tagged, &page->flags)) {
+ if (try_page_mte_tagging(page)) {
mte_clear_page_tags(page_address(page));
- set_bit(PG_mte_tagged, &page->flags);
+ set_page_mte_tagged(page);
}
}
+}
- return 0;
+static bool kvm_vma_mte_allowed(struct vm_area_struct *vma)
+{
+ return vma->vm_flags & VM_MTE_ALLOWED;
}
static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
@@ -1127,7 +1194,6 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
bool write_fault, writable, force_pte = false;
bool exec_fault;
bool device = false;
- bool shared;
unsigned long mmu_seq;
struct kvm *kvm = vcpu->kvm;
struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache;
@@ -1136,7 +1202,6 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
gfn_t gfn;
kvm_pfn_t pfn;
bool logging_active = memslot_is_logging(memslot);
- bool use_read_lock = false;
unsigned long fault_level = kvm_vcpu_trap_get_fault_level(vcpu);
unsigned long vma_pagesize, fault_granule;
enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R;
@@ -1171,14 +1236,10 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
if (logging_active) {
force_pte = true;
vma_shift = PAGE_SHIFT;
- use_read_lock = (fault_status == FSC_PERM && write_fault &&
- fault_granule == PAGE_SIZE);
} else {
vma_shift = get_vma_page_shift(vma, hva);
}
- shared = (vma->vm_flags & VM_SHARED);
-
switch (vma_shift) {
#ifndef __PAGETABLE_PMD_FOLDED
case PUD_SHIFT:
@@ -1239,7 +1300,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
*/
smp_rmb();
- pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL,
+ pfn = __gfn_to_pfn_memslot(memslot, gfn, false, false, NULL,
write_fault, &writable, NULL);
if (pfn == KVM_PFN_ERR_HWPOISON) {
kvm_send_hwpoison_signal(hva, vma_shift);
@@ -1271,15 +1332,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
if (exec_fault && device)
return -ENOEXEC;
- /*
- * To reduce MMU contentions and enhance concurrency during dirty
- * logging dirty logging, only acquire read lock for permission
- * relaxation.
- */
- if (use_read_lock)
- read_lock(&kvm->mmu_lock);
- else
- write_lock(&kvm->mmu_lock);
+ read_lock(&kvm->mmu_lock);
pgt = vcpu->arch.hw_mmu->pgt;
if (mmu_invalidate_retry(kvm, mmu_seq))
goto out_unlock;
@@ -1298,13 +1351,13 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
}
if (fault_status != FSC_PERM && !device && kvm_has_mte(kvm)) {
- /* Check the VMM hasn't introduced a new VM_SHARED VMA */
- if (!shared)
- ret = sanitise_mte_tags(kvm, pfn, vma_pagesize);
- else
+ /* Check the VMM hasn't introduced a new disallowed VMA */
+ if (kvm_vma_mte_allowed(vma)) {
+ sanitise_mte_tags(kvm, pfn, vma_pagesize);
+ } else {
ret = -EFAULT;
- if (ret)
goto out_unlock;
+ }
}
if (writable)
@@ -1323,15 +1376,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
* permissions only if vma_pagesize equals fault_granule. Otherwise,
* kvm_pgtable_stage2_map() should be called to change block size.
*/
- if (fault_status == FSC_PERM && vma_pagesize == fault_granule) {
+ if (fault_status == FSC_PERM && vma_pagesize == fault_granule)
ret = kvm_pgtable_stage2_relax_perms(pgt, fault_ipa, prot);
- } else {
- WARN_ONCE(use_read_lock, "Attempted stage-2 map outside of write lock\n");
-
+ else
ret = kvm_pgtable_stage2_map(pgt, fault_ipa, vma_pagesize,
__pfn_to_phys(pfn), prot,
- memcache);
- }
+ memcache, KVM_PGTABLE_WALK_SHARED);
/* Mark the page dirty only if the fault is handled successfully */
if (writable && !ret) {
@@ -1340,10 +1390,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
}
out_unlock:
- if (use_read_lock)
- read_unlock(&kvm->mmu_lock);
- else
- write_unlock(&kvm->mmu_lock);
+ read_unlock(&kvm->mmu_lock);
kvm_set_pfn_accessed(pfn);
kvm_release_pfn_clean(pfn);
return ret != -EAGAIN ? ret : 0;
@@ -1526,15 +1573,18 @@ bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range)
bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
{
kvm_pfn_t pfn = pte_pfn(range->pte);
- int ret;
if (!kvm->arch.mmu.pgt)
return false;
WARN_ON(range->end - range->start != 1);
- ret = sanitise_mte_tags(kvm, pfn, PAGE_SIZE);
- if (ret)
+ /*
+ * If the page isn't tagged, defer to user_mem_abort() for sanitising
+ * the MTE tags. The S2 pte should have been unmapped by
+ * mmu_notifier_invalidate_range_end().
+ */
+ if (kvm_has_mte(kvm) && !page_mte_tagged(pfn_to_page(pfn)))
return false;
/*
@@ -1549,7 +1599,7 @@ bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
*/
kvm_pgtable_stage2_map(kvm->arch.mmu.pgt, range->start << PAGE_SHIFT,
PAGE_SIZE, __pfn_to_phys(pfn),
- KVM_PGTABLE_PROT_R, NULL);
+ KVM_PGTABLE_PROT_R, NULL, 0);
return false;
}
@@ -1618,6 +1668,8 @@ static struct kvm_pgtable_mm_ops kvm_hyp_mm_ops = {
int kvm_mmu_init(u32 *hyp_va_bits)
{
int err;
+ u32 idmap_bits;
+ u32 kernel_bits;
hyp_idmap_start = __pa_symbol(__hyp_idmap_text_start);
hyp_idmap_start = ALIGN_DOWN(hyp_idmap_start, PAGE_SIZE);
@@ -1631,7 +1683,31 @@ int kvm_mmu_init(u32 *hyp_va_bits)
*/
BUG_ON((hyp_idmap_start ^ (hyp_idmap_end - 1)) & PAGE_MASK);
- *hyp_va_bits = 64 - ((idmap_t0sz & TCR_T0SZ_MASK) >> TCR_T0SZ_OFFSET);
+ /*
+ * The ID map may be configured to use an extended virtual address
+ * range. This is only the case if system RAM is out of range for the
+ * currently configured page size and VA_BITS_MIN, in which case we will
+ * also need the extended virtual range for the HYP ID map, or we won't
+ * be able to enable the EL2 MMU.
+ *
+ * However, in some cases the ID map may be configured for fewer than
+ * the number of VA bits used by the regular kernel stage 1. This
+ * happens when VA_BITS=52 and the kernel image is placed in PA space
+ * below 48 bits.
+ *
+ * At EL2, there is only one TTBR register, and we can't switch between
+ * translation tables *and* update TCR_EL2.T0SZ at the same time. Bottom
+ * line: we need to use the extended range with *both* our translation
+ * tables.
+ *
+ * So use the maximum of the idmap VA bits and the regular kernel stage
+ * 1 VA bits to assure that the hypervisor can both ID map its code page
+ * and map any kernel memory.
+ */
+ idmap_bits = 64 - ((idmap_t0sz & TCR_T0SZ_MASK) >> TCR_T0SZ_OFFSET);
+ kernel_bits = vabits_actual;
+ *hyp_va_bits = max(idmap_bits, kernel_bits);
+
kvm_debug("Using %u-bit virtual addresses at EL2\n", *hyp_va_bits);
kvm_debug("IDMAP page: %lx\n", hyp_idmap_start);
kvm_debug("HYP VA range: %lx:%lx\n",
@@ -1740,12 +1816,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
if (!vma)
break;
- /*
- * VM_SHARED mappings are not allowed with MTE to avoid races
- * when updating the PG_mte_tagged page flag, see
- * sanitise_mte_tags for more details.
- */
- if (kvm_has_mte(kvm) && vma->vm_flags & VM_SHARED) {
+ if (kvm_has_mte(kvm) && !kvm_vma_mte_allowed(vma)) {
ret = -EINVAL;
break;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-16 21:37:32 +0000