Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:

   - Initial infrastructure for shadow stage-2 MMUs, as part of nested
     virtualization enablement

   - Support for userspace changes to the guest CTR_EL0 value, enabling
     (in part) migration of VMs between heterogenous hardware

   - Fixes + improvements to pKVM's FF-A proxy, adding support for v1.1
     of the protocol

   - FPSIMD/SVE support for nested, including merged trap configuration
     and exception routing

   - New command-line parameter to control the WFx trap behavior under
     KVM

   - Introduce kCFI hardening in the EL2 hypervisor

   - Fixes + cleanups for handling presence/absence of FEAT_TCRX

   - Miscellaneous fixes + documentation updates

  LoongArch:

   - Add paravirt steal time support

   - Add support for KVM_DIRTY_LOG_INITIALLY_SET

   - Add perf kvm-stat support for loongarch

  RISC-V:

   - Redirect AMO load/store access fault traps to guest

   - perf kvm stat support

   - Use guest files for IMSIC virtualization, when available

  s390:

   - Assortment of tiny fixes which are not time critical

  x86:

   - Fixes for Xen emulation

   - Add a global struct to consolidate tracking of host values, e.g.
     EFER

   - Add KVM_CAP_X86_APIC_BUS_CYCLES_NS to allow configuring the
     effective APIC bus frequency, because TDX

   - Print the name of the APICv/AVIC inhibits in the relevant
     tracepoint

   - Clean up KVM's handling of vendor specific emulation to
     consistently act on "compatible with Intel/AMD", versus checking
     for a specific vendor

   - Drop MTRR virtualization, and instead always honor guest PAT on
     CPUs that support self-snoop

   - Update to the newfangled Intel CPU FMS infrastructure

   - Don't advertise IA32_PERF_GLOBAL_OVF_CTRL as an MSR-to-be-saved, as
     it reads '0' and writes from userspace are ignored

   - Misc cleanups

  x86 - MMU:

   - Small cleanups, renames and refactoring extracted from the upcoming
     Intel TDX support

   - Don't allocate kvm_mmu_page.shadowed_translation for shadow pages
     that can't hold leafs SPTEs

   - Unconditionally drop mmu_lock when allocating TDP MMU page tables
     for eager page splitting, to avoid stalling vCPUs when splitting
     huge pages

   - Bug the VM instead of simply warning if KVM tries to split a SPTE
     that is non-present or not-huge. KVM is guaranteed to end up in a
     broken state because the callers fully expect a valid SPTE, it's
     all but dangerous to let more MMU changes happen afterwards

  x86 - AMD:

   - Make per-CPU save_area allocations NUMA-aware

   - Force sev_es_host_save_area() to be inlined to avoid calling into
     an instrumentable function from noinstr code

   - Base support for running SEV-SNP guests. API-wise, this includes a
     new KVM_X86_SNP_VM type, encrypting/measure the initial image into
     guest memory, and finalizing it before launching it. Internally,
     there are some gmem/mmu hooks needed to prepare gmem-allocated
     pages before mapping them into guest private memory ranges

     This includes basic support for attestation guest requests, enough
     to say that KVM supports the GHCB 2.0 specification

     There is no support yet for loading into the firmware those signing
     keys to be used for attestation requests, and therefore no need yet
     for the host to provide certificate data for those keys.

     To support fetching certificate data from userspace, a new KVM exit
     type will be needed to handle fetching the certificate from
     userspace.

     An attempt to define a new KVM_EXIT_COCO / KVM_EXIT_COCO_REQ_CERTS
     exit type to handle this was introduced in v1 of this patchset, but
     is still being discussed by community, so for now this patchset
     only implements a stub version of SNP Extended Guest Requests that
     does not provide certificate data

  x86 - Intel:

   - Remove an unnecessary EPT TLB flush when enabling hardware

   - Fix a series of bugs that cause KVM to fail to detect nested
     pending posted interrupts as valid wake eents for a vCPU executing
     HLT in L2 (with HLT-exiting disable by L1)

   - KVM: x86: Suppress MMIO that is triggered during task switch
     emulation

     Explicitly suppress userspace emulated MMIO exits that are
     triggered when emulating a task switch as KVM doesn't support
     userspace MMIO during complex (multi-step) emulation

     Silently ignoring the exit request can result in the
     WARN_ON_ONCE(vcpu->mmio_needed) firing if KVM exits to userspace
     for some other reason prior to purging mmio_needed

     See commit 0dc902267cb3 ("KVM: x86: Suppress pending MMIO write
     exits if emulator detects exception") for more details on KVM's
     limitations with respect to emulated MMIO during complex emulator
     flows

  Generic:

   - Rename the AS_UNMOVABLE flag that was introduced for KVM to
     AS_INACCESSIBLE, because the special casing needed by these pages
     is not due to just unmovability (and in fact they are only
     unmovable because the CPU cannot access them)

   - New ioctl to populate the KVM page tables in advance, which is
     useful to mitigate KVM page faults during guest boot or after live
     migration. The code will also be used by TDX, but (probably) not
     through the ioctl

   - Enable halt poll shrinking by default, as Intel found it to be a
     clear win

   - Setup empty IRQ routing when creating a VM to avoid having to
     synchronize SRCU when creating a split IRQCHIP on x86

   - Rework the sched_in/out() paths to replace kvm_arch_sched_in() with
     a flag that arch code can use for hooking both sched_in() and
     sched_out()

   - Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
     truncating a bogus value from userspace, e.g. to help userspace
     detect bugs

   - Mark a vCPU as preempted if and only if it's scheduled out while in
     the KVM_RUN loop, e.g. to avoid marking it preempted and thus
     writing guest memory when retrieving guest state during live
     migration blackout

  Selftests:

   - Remove dead code in the memslot modification stress test

   - Treat "branch instructions retired" as supported on all AMD Family
     17h+ CPUs

   - Print the guest pseudo-RNG seed only when it changes, to avoid
     spamming the log for tests that create lots of VMs

   - Make the PMU counters test less flaky when counting LLC cache
     misses by doing CLFLUSH{OPT} in every loop iteration"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
  crypto: ccp: Add the SNP_VLEK_LOAD command
  KVM: x86/pmu: Add kvm_pmu_call() to simplify static calls of kvm_pmu_ops
  KVM: x86: Introduce kvm_x86_call() to simplify static calls of kvm_x86_ops
  KVM: x86: Replace static_call_cond() with static_call()
  KVM: SEV: Provide support for SNP_EXTENDED_GUEST_REQUEST NAE event
  x86/sev: Move sev_guest.h into common SEV header
  KVM: SEV: Provide support for SNP_GUEST_REQUEST NAE event
  KVM: x86: Suppress MMIO that is triggered during task switch emulation
  KVM: x86/mmu: Clean up make_huge_page_split_spte() definition and intro
  KVM: x86/mmu: Bug the VM if KVM tries to split a !hugepage SPTE
  KVM: selftests: x86: Add test for KVM_PRE_FAULT_MEMORY
  KVM: x86: Implement kvm_arch_vcpu_pre_fault_memory()
  KVM: x86/mmu: Make kvm_mmu_do_page_fault() return mapped level
  KVM: x86/mmu: Account pf_{fixed,emulate,spurious} in callers of "do page fault"
  KVM: x86/mmu: Bump pf_taken stat only in the "real" page fault handler
  KVM: Add KVM_PRE_FAULT_MEMORY vcpu ioctl to pre-populate guest memory
  KVM: Document KVM_PRE_FAULT_MEMORY ioctl
  mm, virt: merge AS_UNMOVABLE and AS_INACCESSIBLE
  perf kvm: Add kvm-stat for loongarch64
  LoongArch: KVM: Add PV steal time support in guest side
  ...

1 files changed, 53 insertions, 83 deletions

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 36539c1b36cd..c7dc49ee7388 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -365,8 +365,8 @@ static void handle_removed_pt(struct kvm *kvm, tdp_ptep_t pt, bool shared)
 			 * value to the removed SPTE value.
 			 */
 			for (;;) {
-				old_spte = kvm_tdp_mmu_write_spte_atomic(sptep, REMOVED_SPTE);
-				if (!is_removed_spte(old_spte))
+				old_spte = kvm_tdp_mmu_write_spte_atomic(sptep, FROZEN_SPTE);
+				if (!is_frozen_spte(old_spte))
 					break;
 				cpu_relax();
 			}
@@ -397,11 +397,11 @@ static void handle_removed_pt(struct kvm *kvm, tdp_ptep_t pt, bool shared)
 			 * No retry is needed in the atomic update path as the
 			 * sole concern is dropping a Dirty bit, i.e. no other
 			 * task can zap/remove the SPTE as mmu_lock is held for
-			 * write.  Marking the SPTE as a removed SPTE is not
+			 * write.  Marking the SPTE as a frozen SPTE is not
 			 * strictly necessary for the same reason, but using
-			 * the remove SPTE value keeps the shared/exclusive
+			 * the frozen SPTE value keeps the shared/exclusive
 			 * paths consistent and allows the handle_changed_spte()
-			 * call below to hardcode the new value to REMOVED_SPTE.
+			 * call below to hardcode the new value to FROZEN_SPTE.
 			 *
 			 * Note, even though dropping a Dirty bit is the only
 			 * scenario where a non-atomic update could result in a
@@ -413,10 +413,10 @@ static void handle_removed_pt(struct kvm *kvm, tdp_ptep_t pt, bool shared)
 			 * it here.
 			 */
 			old_spte = kvm_tdp_mmu_write_spte(sptep, old_spte,
-							  REMOVED_SPTE, level);
+							  FROZEN_SPTE, level);
 		}
 		handle_changed_spte(kvm, kvm_mmu_page_as_id(sp), gfn,
-				    old_spte, REMOVED_SPTE, level, shared);
+				    old_spte, FROZEN_SPTE, level, shared);
 	}
 
 	call_rcu(&sp->rcu_head, tdp_mmu_free_sp_rcu_callback);
@@ -490,19 +490,19 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
 	 */
 	if (!was_present && !is_present) {
 		/*
-		 * If this change does not involve a MMIO SPTE or removed SPTE,
+		 * If this change does not involve a MMIO SPTE or frozen SPTE,
 		 * it is unexpected. Log the change, though it should not
 		 * impact the guest since both the former and current SPTEs
 		 * are nonpresent.
 		 */
 		if (WARN_ON_ONCE(!is_mmio_spte(kvm, old_spte) &&
 				 !is_mmio_spte(kvm, new_spte) &&
-				 !is_removed_spte(new_spte)))
+				 !is_frozen_spte(new_spte)))
 			pr_err("Unexpected SPTE change! Nonpresent SPTEs\n"
 			       "should not be replaced with another,\n"
 			       "different nonpresent SPTE, unless one or both\n"
 			       "are MMIO SPTEs, or the new SPTE is\n"
-			       "a temporary removed SPTE.\n"
+			       "a temporary frozen SPTE.\n"
 			       "as_id: %d gfn: %llx old_spte: %llx new_spte: %llx level: %d",
 			       as_id, gfn, old_spte, new_spte, level);
 		return;
@@ -530,7 +530,8 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
 		kvm_set_pfn_accessed(spte_to_pfn(old_spte));
 }
 
-static inline int __tdp_mmu_set_spte_atomic(struct tdp_iter *iter, u64 new_spte)
+static inline int __must_check __tdp_mmu_set_spte_atomic(struct tdp_iter *iter,
+							 u64 new_spte)
 {
 	u64 *sptep = rcu_dereference(iter->sptep);
 
@@ -540,7 +541,7 @@ static inline int __tdp_mmu_set_spte_atomic(struct tdp_iter *iter, u64 new_spte)
 	 * and pre-checking before inserting a new SPTE is advantageous as it
 	 * avoids unnecessary work.
 	 */
-	WARN_ON_ONCE(iter->yielded || is_removed_spte(iter->old_spte));
+	WARN_ON_ONCE(iter->yielded || is_frozen_spte(iter->old_spte));
 
 	/*
 	 * Note, fast_pf_fix_direct_spte() can also modify TDP MMU SPTEs and
@@ -572,9 +573,9 @@ static inline int __tdp_mmu_set_spte_atomic(struct tdp_iter *iter, u64 new_spte)
  *            no side-effects other than setting iter->old_spte to the last
  *            known value of the spte.
  */
-static inline int tdp_mmu_set_spte_atomic(struct kvm *kvm,
-					  struct tdp_iter *iter,
-					  u64 new_spte)
+static inline int __must_check tdp_mmu_set_spte_atomic(struct kvm *kvm,
+						       struct tdp_iter *iter,
+						       u64 new_spte)
 {
 	int ret;
 
@@ -590,8 +591,8 @@ static inline int tdp_mmu_set_spte_atomic(struct kvm *kvm,
 	return 0;
 }
 
-static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
-					  struct tdp_iter *iter)
+static inline int __must_check tdp_mmu_zap_spte_atomic(struct kvm *kvm,
+						       struct tdp_iter *iter)
 {
 	int ret;
 
@@ -603,26 +604,26 @@ static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
 	 * in its place before the TLBs are flushed.
 	 *
 	 * Delay processing of the zapped SPTE until after TLBs are flushed and
-	 * the REMOVED_SPTE is replaced (see below).
+	 * the FROZEN_SPTE is replaced (see below).
 	 */
-	ret = __tdp_mmu_set_spte_atomic(iter, REMOVED_SPTE);
+	ret = __tdp_mmu_set_spte_atomic(iter, FROZEN_SPTE);
 	if (ret)
 		return ret;
 
 	kvm_flush_remote_tlbs_gfn(kvm, iter->gfn, iter->level);
 
 	/*
-	 * No other thread can overwrite the removed SPTE as they must either
+	 * No other thread can overwrite the frozen SPTE as they must either
 	 * wait on the MMU lock or use tdp_mmu_set_spte_atomic() which will not
-	 * overwrite the special removed SPTE value. Use the raw write helper to
+	 * overwrite the special frozen SPTE value. Use the raw write helper to
 	 * avoid an unnecessary check on volatile bits.
 	 */
 	__kvm_tdp_mmu_write_spte(iter->sptep, SHADOW_NONPRESENT_VALUE);
 
 	/*
 	 * Process the zapped SPTE after flushing TLBs, and after replacing
-	 * REMOVED_SPTE with 0. This minimizes the amount of time vCPUs are
-	 * blocked by the REMOVED_SPTE and reduces contention on the child
+	 * FROZEN_SPTE with 0. This minimizes the amount of time vCPUs are
+	 * blocked by the FROZEN_SPTE and reduces contention on the child
 	 * SPTEs.
 	 */
 	handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte,
@@ -652,12 +653,12 @@ static u64 tdp_mmu_set_spte(struct kvm *kvm, int as_id, tdp_ptep_t sptep,
 
 	/*
 	 * No thread should be using this function to set SPTEs to or from the
-	 * temporary removed SPTE value.
+	 * temporary frozen SPTE value.
 	 * If operating under the MMU lock in read mode, tdp_mmu_set_spte_atomic
 	 * should be used. If operating under the MMU lock in write mode, the
-	 * use of the removed SPTE should not be necessary.
+	 * use of the frozen SPTE should not be necessary.
 	 */
-	WARN_ON_ONCE(is_removed_spte(old_spte) || is_removed_spte(new_spte));
+	WARN_ON_ONCE(is_frozen_spte(old_spte) || is_frozen_spte(new_spte));
 
 	old_spte = kvm_tdp_mmu_write_spte(sptep, old_spte, new_spte, level);
 
@@ -1126,7 +1127,7 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
 		 * If SPTE has been frozen by another thread, just give up and
 		 * retry, avoiding unnecessary page table allocation and free.
 		 */
-		if (is_removed_spte(iter.old_spte))
+		if (is_frozen_spte(iter.old_spte))
 			goto retry;
 
 		if (iter.level == fault->goal_level)
@@ -1339,17 +1340,15 @@ bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm,
 	return spte_set;
 }
 
-static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(gfp_t gfp)
+static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_split(void)
 {
 	struct kvm_mmu_page *sp;
 
-	gfp |= __GFP_ZERO;
-
-	sp = kmem_cache_alloc(mmu_page_header_cache, gfp);
+	sp = kmem_cache_zalloc(mmu_page_header_cache, GFP_KERNEL_ACCOUNT);
 	if (!sp)
 		return NULL;
 
-	sp->spt = (void *)__get_free_page(gfp);
+	sp->spt = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);
 	if (!sp->spt) {
 		kmem_cache_free(mmu_page_header_cache, sp);
 		return NULL;
@@ -1358,47 +1357,6 @@ static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(gfp_t gfp)
 	return sp;
 }
 
-static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_split(struct kvm *kvm,
-						       struct tdp_iter *iter,
-						       bool shared)
-{
-	struct kvm_mmu_page *sp;
-
-	kvm_lockdep_assert_mmu_lock_held(kvm, shared);
-
-	/*
-	 * Since we are allocating while under the MMU lock we have to be
-	 * careful about GFP flags. Use GFP_NOWAIT to avoid blocking on direct
-	 * reclaim and to avoid making any filesystem callbacks (which can end
-	 * up invoking KVM MMU notifiers, resulting in a deadlock).
-	 *
-	 * If this allocation fails we drop the lock and retry with reclaim
-	 * allowed.
-	 */
-	sp = __tdp_mmu_alloc_sp_for_split(GFP_NOWAIT | __GFP_ACCOUNT);
-	if (sp)
-		return sp;
-
-	rcu_read_unlock();
-
-	if (shared)
-		read_unlock(&kvm->mmu_lock);
-	else
-		write_unlock(&kvm->mmu_lock);
-
-	iter->yielded = true;
-	sp = __tdp_mmu_alloc_sp_for_split(GFP_KERNEL_ACCOUNT);
-
-	if (shared)
-		read_lock(&kvm->mmu_lock);
-	else
-		write_lock(&kvm->mmu_lock);
-
-	rcu_read_lock();
-
-	return sp;
-}
-
 /* Note, the caller is responsible for initializing @sp. */
 static int tdp_mmu_split_huge_page(struct kvm *kvm, struct tdp_iter *iter,
 				   struct kvm_mmu_page *sp, bool shared)
@@ -1445,7 +1403,6 @@ static int tdp_mmu_split_huge_pages_root(struct kvm *kvm,
 {
 	struct kvm_mmu_page *sp = NULL;
 	struct tdp_iter iter;
-	int ret = 0;
 
 	rcu_read_lock();
 
@@ -1469,17 +1426,31 @@ retry:
 			continue;
 
 		if (!sp) {
-			sp = tdp_mmu_alloc_sp_for_split(kvm, &iter, shared);
+			rcu_read_unlock();
+
+			if (shared)
+				read_unlock(&kvm->mmu_lock);
+			else
+				write_unlock(&kvm->mmu_lock);
+
+			sp = tdp_mmu_alloc_sp_for_split();
+
+			if (shared)
+				read_lock(&kvm->mmu_lock);
+			else
+				write_lock(&kvm->mmu_lock);
+
 			if (!sp) {
-				ret = -ENOMEM;
 				trace_kvm_mmu_split_huge_page(iter.gfn,
 							      iter.old_spte,
-							      iter.level, ret);
-				break;
+							      iter.level, -ENOMEM);
+				return -ENOMEM;
 			}
 
-			if (iter.yielded)
-				continue;
+			rcu_read_lock();
+
+			iter.yielded = true;
+			continue;
 		}
 
 		tdp_mmu_init_child_sp(sp, &iter);
@@ -1500,7 +1471,7 @@ retry:
 	if (sp)
 		tdp_mmu_free_sp(sp);
 
-	return ret;
+	return 0;
 }
 
 
@@ -1801,12 +1772,11 @@ int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes,
  *
  * WARNING: This function is only intended to be called during fast_page_fault.
  */
-u64 *kvm_tdp_mmu_fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, u64 addr,
+u64 *kvm_tdp_mmu_fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, gfn_t gfn,
 					u64 *spte)
 {
 	struct tdp_iter iter;
 	struct kvm_mmu *mmu = vcpu->arch.mmu;
-	gfn_t gfn = addr >> PAGE_SHIFT;
 	tdp_ptep_t sptep = NULL;
 
 	tdp_mmu_for_each_pte(iter, mmu, gfn, gfn + 1) {