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

Pull kvm fixes from Paolo Bonzini:
 "s390:

   - Fix failure to start guests with kvm.use_gisa=0

   - Panic if (un)share fails to maintain security.

  ARM:

   - Use kvfree() for the kvmalloc'd nested MMUs array

   - Set of fixes to address warnings in W=1 builds

   - Make KVM depend on assembler support for ARMv8.4

   - Fix for vgic-debug interface for VMs without LPIs

   - Actually check ID_AA64MMFR3_EL1.S1PIE in get-reg-list selftest

   - Minor code / comment cleanups for configuring PAuth traps

   - Take kvm->arch.config_lock to prevent destruction / initialization
     race for a vCPU's CPUIF which may lead to a UAF

  x86:

   - Disallow read-only memslots for SEV-ES and SEV-SNP (and TDX)

   - Fix smatch issues

   - Small cleanups

   - Make x2APIC ID 100% readonly

   - Fix typo in uapi constant

  Generic:

   - Use synchronize_srcu_expedited() on irqfd shutdown"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (21 commits)
  KVM: SEV: uapi: fix typo in SEV_RET_INVALID_CONFIG
  KVM: x86: Disallow read-only memslots for SEV-ES and SEV-SNP (and TDX)
  KVM: eventfd: Use synchronize_srcu_expedited() on shutdown
  KVM: selftests: Add a testcase to verify x2APIC is fully readonly
  KVM: x86: Make x2APIC ID 100% readonly
  KVM: x86: Use this_cpu_ptr() instead of per_cpu_ptr(smp_processor_id())
  KVM: x86: hyper-v: Remove unused inline function kvm_hv_free_pa_page()
  KVM: SVM: Fix an error code in sev_gmem_post_populate()
  KVM: SVM: Fix uninitialized variable bug
  KVM: arm64: vgic: Hold config_lock while tearing down a CPU interface
  KVM: selftests: arm64: Correct feature test for S1PIE in get-reg-list
  KVM: arm64: Tidying up PAuth code in KVM
  KVM: arm64: vgic-debug: Exit the iterator properly w/o LPI
  KVM: arm64: Enforce dependency on an ARMv8.4-aware toolchain
  s390/uv: Panic for set and remove shared access UVC errors
  KVM: s390: fix validity interception issue when gisa is switched off
  docs: KVM: Fix register ID of SPSR_FIQ
  KVM: arm64: vgic: fix unexpected unlock sparse warnings
  KVM: arm64: fix kdoc warnings in W=1 builds
  KVM: arm64: fix override-init warnings in W=1 builds
  ...

2 files changed, 9 insertions, 9 deletions

diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 229570059a1b..992f9beb3e7d 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -97,18 +97,19 @@ irqfd_resampler_shutdown(struct kvm_kernel_irqfd *irqfd)
 	mutex_lock(&kvm->irqfds.resampler_lock);
 
 	list_del_rcu(&irqfd->resampler_link);
-	synchronize_srcu(&kvm->irq_srcu);
 
 	if (list_empty(&resampler->list)) {
 		list_del_rcu(&resampler->link);
 		kvm_unregister_irq_ack_notifier(kvm, &resampler->notifier);
 		/*
-		 * synchronize_srcu(&kvm->irq_srcu) already called
+		 * synchronize_srcu_expedited(&kvm->irq_srcu) already called
 		 * in kvm_unregister_irq_ack_notifier().
 		 */
 		kvm_set_irq(kvm, KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID,
 			    resampler->notifier.gsi, 0, false);
 		kfree(resampler);
+	} else {
+		synchronize_srcu_expedited(&kvm->irq_srcu);
 	}
 
 	mutex_unlock(&kvm->irqfds.resampler_lock);
@@ -126,7 +127,7 @@ irqfd_shutdown(struct work_struct *work)
 	u64 cnt;
 
 	/* Make sure irqfd has been initialized in assign path. */
-	synchronize_srcu(&kvm->irq_srcu);
+	synchronize_srcu_expedited(&kvm->irq_srcu);
 
 	/*
 	 * Synchronize with the wait-queue and unhook ourselves to prevent
@@ -384,7 +385,7 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
 		}
 
 		list_add_rcu(&irqfd->resampler_link, &irqfd->resampler->list);
-		synchronize_srcu(&kvm->irq_srcu);
+		synchronize_srcu_expedited(&kvm->irq_srcu);
 
 		mutex_unlock(&kvm->irqfds.resampler_lock);
 	}
@@ -523,7 +524,7 @@ void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
 	mutex_lock(&kvm->irq_lock);
 	hlist_del_init_rcu(&kian->link);
 	mutex_unlock(&kvm->irq_lock);
-	synchronize_srcu(&kvm->irq_srcu);
+	synchronize_srcu_expedited(&kvm->irq_srcu);
 	kvm_arch_post_irq_ack_notifier_list_update(kvm);
 }
 
@@ -608,7 +609,7 @@ kvm_irqfd_release(struct kvm *kvm)
 
 /*
  * Take note of a change in irq routing.
- * Caller must invoke synchronize_srcu(&kvm->irq_srcu) afterwards.
+ * Caller must invoke synchronize_srcu_expedited(&kvm->irq_srcu) afterwards.
  */
 void kvm_irq_routing_update(struct kvm *kvm)
 {
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 92901656a0d4..cb2b78e92910 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1578,15 +1578,14 @@ static int check_memory_region_flags(struct kvm *kvm,
 	if (mem->flags & KVM_MEM_GUEST_MEMFD)
 		valid_flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 
-#ifdef CONFIG_HAVE_KVM_READONLY_MEM
 	/*
 	 * GUEST_MEMFD is incompatible with read-only memslots, as writes to
 	 * read-only memslots have emulated MMIO, not page fault, semantics,
 	 * and KVM doesn't allow emulated MMIO for private memory.
 	 */
-	if (!(mem->flags & KVM_MEM_GUEST_MEMFD))
+	if (kvm_arch_has_readonly_mem(kvm) &&
+	    !(mem->flags & KVM_MEM_GUEST_MEMFD))
 		valid_flags |= KVM_MEM_READONLY;
-#endif
 
 	if (mem->flags & ~valid_flags)
 		return -EINVAL;