From: Claudio Imbrenda <imbrenda@linux.ibm.com>
Date: Wed, 4 Feb 2026 15:02:35 +0000 (+0100)
Subject: KVM: s390: Introduce import_lock
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cf3ce3d69d56bd3ef2bc5f6b500ebc5181637161;p=thirdparty%2Flinux.git

KVM: s390: Introduce import_lock

Introduce import_lock to avoid future races when converting pages to
secure.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
---

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index ae1223264d3cd..3dbddb7c60a99 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -630,6 +630,8 @@ struct kvm_s390_pv {
 	void *set_aside;
 	struct list_head need_cleanup;
 	struct mmu_notifier mmu_notifier;
+	/* Protects against concurrent import-like operations */
+	struct mutex import_lock;
 };
 
 struct kvm_arch {
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 56a50524b3eee..cd39b2f099ca7 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -3330,6 +3330,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	char debug_name[16];
 	int i, rc;
 
+	mutex_init(&kvm->arch.pv.import_lock);
+
 	rc = -EINVAL;
 #ifdef CONFIG_KVM_S390_UCONTROL
 	if (type & ~KVM_VM_S390_UCONTROL)