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authorLinus Torvalds <torvalds@linux-foundation.org>2019-07-12 15:35:14 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-07-12 15:35:14 -0700
commit39d7530d7494b4e47ba1856e741f513dafd17e3d (patch)
tree6b16a744047cff9ff77f26bc5811fe9d953a9b91 /arch/x86/kvm/mmu.c
parent16c97650a56abdd067f7da079007b7e00b307083 (diff)
parenta45ff5994c9cde41af627c46abb9f32beae68943 (diff)
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini: "ARM: - support for chained PMU counters in guests - improved SError handling - handle Neoverse N1 erratum #1349291 - allow side-channel mitigation status to be migrated - standardise most AArch64 system register accesses to msr_s/mrs_s - fix host MPIDR corruption on 32bit - selftests ckleanups x86: - PMU event {white,black}listing - ability for the guest to disable host-side interrupt polling - fixes for enlightened VMCS (Hyper-V pv nested virtualization), - new hypercall to yield to IPI target - support for passing cstate MSRs through to the guest - lots of cleanups and optimizations Generic: - Some txt->rST conversions for the documentation" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (128 commits) Documentation: virtual: Add toctree hooks Documentation: kvm: Convert cpuid.txt to .rst Documentation: virtual: Convert paravirt_ops.txt to .rst KVM: x86: Unconditionally enable irqs in guest context KVM: x86: PMU Event Filter kvm: x86: Fix -Wmissing-prototypes warnings KVM: Properly check if "page" is valid in kvm_vcpu_unmap KVM: arm/arm64: Initialise host's MPIDRs by reading the actual register KVM: LAPIC: Retry tune per-vCPU timer_advance_ns if adaptive tuning goes insane kvm: LAPIC: write down valid APIC registers KVM: arm64: Migrate _elx sysreg accessors to msr_s/mrs_s KVM: doc: Add API documentation on the KVM_REG_ARM_WORKAROUNDS register KVM: arm/arm64: Add save/restore support for firmware workaround state arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests KVM: arm/arm64: Support chained PMU counters KVM: arm/arm64: Remove pmc->bitmask KVM: arm/arm64: Re-create event when setting counter value KVM: arm/arm64: Extract duplicated code to own function KVM: arm/arm64: Rename kvm_pmu_{enable/disable}_counter functions KVM: LAPIC: ARBPRI is a reserved register for x2APIC ...
Diffstat (limited to 'arch/x86/kvm/mmu.c')
-rw-r--r--arch/x86/kvm/mmu.c182
1 files changed, 108 insertions, 74 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 4a9c63d1c20a..9a5814d8d194 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -140,9 +140,6 @@ module_param(dbg, bool, 0644);
#include <trace/events/kvm.h>
-#define CREATE_TRACE_POINTS
-#include "mmutrace.h"
-
#define SPTE_HOST_WRITEABLE (1ULL << PT_FIRST_AVAIL_BITS_SHIFT)
#define SPTE_MMU_WRITEABLE (1ULL << (PT_FIRST_AVAIL_BITS_SHIFT + 1))
@@ -259,11 +256,20 @@ static const u64 shadow_nonpresent_or_rsvd_mask_len = 5;
*/
static u64 __read_mostly shadow_nonpresent_or_rsvd_lower_gfn_mask;
+/*
+ * The number of non-reserved physical address bits irrespective of features
+ * that repurpose legal bits, e.g. MKTME.
+ */
+static u8 __read_mostly shadow_phys_bits;
static void mmu_spte_set(u64 *sptep, u64 spte);
+static bool is_executable_pte(u64 spte);
static union kvm_mmu_page_role
kvm_mmu_calc_root_page_role(struct kvm_vcpu *vcpu);
+#define CREATE_TRACE_POINTS
+#include "mmutrace.h"
+
static inline bool kvm_available_flush_tlb_with_range(void)
{
@@ -468,6 +474,21 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
}
EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes);
+static u8 kvm_get_shadow_phys_bits(void)
+{
+ /*
+ * boot_cpu_data.x86_phys_bits is reduced when MKTME is detected
+ * in CPU detection code, but MKTME treats those reduced bits as
+ * 'keyID' thus they are not reserved bits. Therefore for MKTME
+ * we should still return physical address bits reported by CPUID.
+ */
+ if (!boot_cpu_has(X86_FEATURE_TME) ||
+ WARN_ON_ONCE(boot_cpu_data.extended_cpuid_level < 0x80000008))
+ return boot_cpu_data.x86_phys_bits;
+
+ return cpuid_eax(0x80000008) & 0xff;
+}
+
static void kvm_mmu_reset_all_pte_masks(void)
{
u8 low_phys_bits;
@@ -481,6 +502,8 @@ static void kvm_mmu_reset_all_pte_masks(void)
shadow_present_mask = 0;
shadow_acc_track_mask = 0;
+ shadow_phys_bits = kvm_get_shadow_phys_bits();
+
/*
* If the CPU has 46 or less physical address bits, then set an
* appropriate mask to guard against L1TF attacks. Otherwise, it is
@@ -1073,10 +1096,16 @@ static gfn_t kvm_mmu_page_get_gfn(struct kvm_mmu_page *sp, int index)
static void kvm_mmu_page_set_gfn(struct kvm_mmu_page *sp, int index, gfn_t gfn)
{
- if (sp->role.direct)
- BUG_ON(gfn != kvm_mmu_page_get_gfn(sp, index));
- else
+ if (!sp->role.direct) {
sp->gfns[index] = gfn;
+ return;
+ }
+
+ if (WARN_ON(gfn != kvm_mmu_page_get_gfn(sp, index)))
+ pr_err_ratelimited("gfn mismatch under direct page %llx "
+ "(expected %llx, got %llx)\n",
+ sp->gfn,
+ kvm_mmu_page_get_gfn(sp, index), gfn);
}
/*
@@ -3055,10 +3084,7 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, unsigned pte_access,
ret = RET_PF_EMULATE;
pgprintk("%s: setting spte %llx\n", __func__, *sptep);
- pgprintk("instantiating %s PTE (%s) at %llx (%llx) addr %p\n",
- is_large_pte(*sptep)? "2MB" : "4kB",
- *sptep & PT_WRITABLE_MASK ? "RW" : "R", gfn,
- *sptep, sptep);
+ trace_kvm_mmu_set_spte(level, gfn, sptep);
if (!was_rmapped && is_large_pte(*sptep))
++vcpu->kvm->stat.lpages;
@@ -3070,8 +3096,6 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, unsigned pte_access,
}
}
- kvm_release_pfn_clean(pfn);
-
return ret;
}
@@ -3106,9 +3130,11 @@ static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu,
if (ret <= 0)
return -1;
- for (i = 0; i < ret; i++, gfn++, start++)
+ for (i = 0; i < ret; i++, gfn++, start++) {
mmu_set_spte(vcpu, start, access, 0, sp->role.level, gfn,
page_to_pfn(pages[i]), true, true);
+ put_page(pages[i]);
+ }
return 0;
}
@@ -3156,40 +3182,40 @@ static void direct_pte_prefetch(struct kvm_vcpu *vcpu, u64 *sptep)
__direct_pte_prefetch(vcpu, sp, sptep);
}
-static int __direct_map(struct kvm_vcpu *vcpu, int write, int map_writable,
- int level, gfn_t gfn, kvm_pfn_t pfn, bool prefault)
+static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, int write,
+ int map_writable, int level, kvm_pfn_t pfn,
+ bool prefault)
{
- struct kvm_shadow_walk_iterator iterator;
+ struct kvm_shadow_walk_iterator it;
struct kvm_mmu_page *sp;
- int emulate = 0;
- gfn_t pseudo_gfn;
+ int ret;
+ gfn_t gfn = gpa >> PAGE_SHIFT;
+ gfn_t base_gfn = gfn;
if (!VALID_PAGE(vcpu->arch.mmu->root_hpa))
- return 0;
+ return RET_PF_RETRY;
- for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) {
- if (iterator.level == level) {
- emulate = mmu_set_spte(vcpu, iterator.sptep, ACC_ALL,
- write, level, gfn, pfn, prefault,
- map_writable);
- direct_pte_prefetch(vcpu, iterator.sptep);
- ++vcpu->stat.pf_fixed;
+ trace_kvm_mmu_spte_requested(gpa, level, pfn);
+ for_each_shadow_entry(vcpu, gpa, it) {
+ base_gfn = gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1);
+ if (it.level == level)
break;
- }
- drop_large_spte(vcpu, iterator.sptep);
- if (!is_shadow_present_pte(*iterator.sptep)) {
- u64 base_addr = iterator.addr;
+ drop_large_spte(vcpu, it.sptep);
+ if (!is_shadow_present_pte(*it.sptep)) {
+ sp = kvm_mmu_get_page(vcpu, base_gfn, it.addr,
+ it.level - 1, true, ACC_ALL);
- base_addr &= PT64_LVL_ADDR_MASK(iterator.level);
- pseudo_gfn = base_addr >> PAGE_SHIFT;
- sp = kvm_mmu_get_page(vcpu, pseudo_gfn, iterator.addr,
- iterator.level - 1, 1, ACC_ALL);
-
- link_shadow_page(vcpu, iterator.sptep, sp);
+ link_shadow_page(vcpu, it.sptep, sp);
}
}
- return emulate;
+
+ ret = mmu_set_spte(vcpu, it.sptep, ACC_ALL,
+ write, level, base_gfn, pfn, prefault,
+ map_writable);
+ direct_pte_prefetch(vcpu, it.sptep);
+ ++vcpu->stat.pf_fixed;
+ return ret;
}
static void kvm_send_hwpoison_signal(unsigned long address, struct task_struct *tsk)
@@ -3216,11 +3242,10 @@ static int kvm_handle_bad_page(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn)
}
static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
- gfn_t *gfnp, kvm_pfn_t *pfnp,
+ gfn_t gfn, kvm_pfn_t *pfnp,
int *levelp)
{
kvm_pfn_t pfn = *pfnp;
- gfn_t gfn = *gfnp;
int level = *levelp;
/*
@@ -3247,8 +3272,6 @@ static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
mask = KVM_PAGES_PER_HPAGE(level) - 1;
VM_BUG_ON((gfn & mask) != (pfn & mask));
if (pfn & mask) {
- gfn &= ~mask;
- *gfnp = gfn;
kvm_release_pfn_clean(pfn);
pfn &= ~mask;
kvm_get_pfn(pfn);
@@ -3505,22 +3528,19 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code,
if (handle_abnormal_pfn(vcpu, v, gfn, pfn, ACC_ALL, &r))
return r;
+ r = RET_PF_RETRY;
spin_lock(&vcpu->kvm->mmu_lock);
if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
goto out_unlock;
if (make_mmu_pages_available(vcpu) < 0)
goto out_unlock;
if (likely(!force_pt_level))
- transparent_hugepage_adjust(vcpu, &gfn, &pfn, &level);
- r = __direct_map(vcpu, write, map_writable, level, gfn, pfn, prefault);
- spin_unlock(&vcpu->kvm->mmu_lock);
-
- return r;
-
+ transparent_hugepage_adjust(vcpu, gfn, &pfn, &level);
+ r = __direct_map(vcpu, v, write, map_writable, level, pfn, prefault);
out_unlock:
spin_unlock(&vcpu->kvm->mmu_lock);
kvm_release_pfn_clean(pfn);
- return RET_PF_RETRY;
+ return r;
}
static void mmu_free_root_page(struct kvm *kvm, hpa_t *root_hpa,
@@ -4015,19 +4035,6 @@ static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn)
return kvm_setup_async_pf(vcpu, gva, kvm_vcpu_gfn_to_hva(vcpu, gfn), &arch);
}
-bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu)
-{
- if (unlikely(!lapic_in_kernel(vcpu) ||
- kvm_event_needs_reinjection(vcpu) ||
- vcpu->arch.exception.pending))
- return false;
-
- if (!vcpu->arch.apf.delivery_as_pf_vmexit && is_guest_mode(vcpu))
- return false;
-
- return kvm_x86_ops->interrupt_allowed(vcpu);
-}
-
static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
gva_t gva, kvm_pfn_t *pfn, bool write, bool *writable)
{
@@ -4147,22 +4154,19 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code,
if (handle_abnormal_pfn(vcpu, 0, gfn, pfn, ACC_ALL, &r))
return r;
+ r = RET_PF_RETRY;
spin_lock(&vcpu->kvm->mmu_lock);
if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
goto out_unlock;
if (make_mmu_pages_available(vcpu) < 0)
goto out_unlock;
if (likely(!force_pt_level))
- transparent_hugepage_adjust(vcpu, &gfn, &pfn, &level);
- r = __direct_map(vcpu, write, map_writable, level, gfn, pfn, prefault);
- spin_unlock(&vcpu->kvm->mmu_lock);
-
- return r;
-
+ transparent_hugepage_adjust(vcpu, gfn, &pfn, &level);
+ r = __direct_map(vcpu, gpa, write, map_writable, level, pfn, prefault);
out_unlock:
spin_unlock(&vcpu->kvm->mmu_lock);
kvm_release_pfn_clean(pfn);
- return RET_PF_RETRY;
+ return r;
}
static void nonpaging_init_context(struct kvm_vcpu *vcpu,
@@ -4494,7 +4498,7 @@ reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, struct kvm_mmu *context)
*/
shadow_zero_check = &context->shadow_zero_check;
__reset_rsvds_bits_mask(vcpu, shadow_zero_check,
- boot_cpu_data.x86_phys_bits,
+ shadow_phys_bits,
context->shadow_root_level, uses_nx,
guest_cpuid_has(vcpu, X86_FEATURE_GBPAGES),
is_pse(vcpu), true);
@@ -4531,13 +4535,13 @@ reset_tdp_shadow_zero_bits_mask(struct kvm_vcpu *vcpu,
if (boot_cpu_is_amd())
__reset_rsvds_bits_mask(vcpu, shadow_zero_check,
- boot_cpu_data.x86_phys_bits,
+ shadow_phys_bits,
context->shadow_root_level, false,
boot_cpu_has(X86_FEATURE_GBPAGES),
true, true);
else
__reset_rsvds_bits_mask_ept(shadow_zero_check,
- boot_cpu_data.x86_phys_bits,
+ shadow_phys_bits,
false);
if (!shadow_me_mask)
@@ -4558,7 +4562,7 @@ reset_ept_shadow_zero_bits_mask(struct kvm_vcpu *vcpu,
struct kvm_mmu *context, bool execonly)
{
__reset_rsvds_bits_mask_ept(&context->shadow_zero_check,
- boot_cpu_data.x86_phys_bits, execonly);
+ shadow_phys_bits, execonly);
}
#define BYTE_MASK(access) \
@@ -5935,7 +5939,7 @@ mmu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
int nr_to_scan = sc->nr_to_scan;
unsigned long freed = 0;
- spin_lock(&kvm_lock);
+ mutex_lock(&kvm_lock);
list_for_each_entry(kvm, &vm_list, vm_list) {
int idx;
@@ -5977,7 +5981,7 @@ mmu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
break;
}
- spin_unlock(&kvm_lock);
+ mutex_unlock(&kvm_lock);
return freed;
}
@@ -5999,6 +6003,34 @@ static void mmu_destroy_caches(void)
kmem_cache_destroy(mmu_page_header_cache);
}
+static void kvm_set_mmio_spte_mask(void)
+{
+ u64 mask;
+
+ /*
+ * Set the reserved bits and the present bit of an paging-structure
+ * entry to generate page fault with PFER.RSV = 1.
+ */
+
+ /*
+ * Mask the uppermost physical address bit, which would be reserved as
+ * long as the supported physical address width is less than 52.
+ */
+ mask = 1ull << 51;
+
+ /* Set the present bit. */
+ mask |= 1ull;
+
+ /*
+ * If reserved bit is not supported, clear the present bit to disable
+ * mmio page fault.
+ */
+ if (IS_ENABLED(CONFIG_X86_64) && shadow_phys_bits == 52)
+ mask &= ~1ull;
+
+ kvm_mmu_set_mmio_spte_mask(mask, mask);
+}
+
int kvm_mmu_module_init(void)
{
int ret = -ENOMEM;
@@ -6015,6 +6047,8 @@ int kvm_mmu_module_init(void)
kvm_mmu_reset_all_pte_masks();
+ kvm_set_mmio_spte_mask();
+
pte_list_desc_cache = kmem_cache_create("pte_list_desc",
sizeof(struct pte_list_desc),
0, SLAB_ACCOUNT, NULL);