KVM: s390: Fix locking in kvm_s390_set_mem_control()

Add the missing locking around dat_reset_cmma().

Fixes: e38c884df921 ("KVM: s390: Switch to new gmap")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260623153331.233784-7-imbrenda@linux.ibm.com>

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8a3d55410f06e03ded6aba38d10b42d4e26230b5..221b2fb199d4ea8a2fdb1582964f8cd3c4a2fc82 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -990,9 +990,11 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att
                if (!kvm->arch.use_cmma)
                        break;
 
+               guard(mutex)(&kvm->lock);
                VM_EVENT(kvm, 3, "%s", "RESET: CMMA states");
                do {
-                       start_gfn = dat_reset_cmma(kvm->arch.gmap->asce, start_gfn);
+                       scoped_guard(read_lock, &kvm->mmu_lock)
+                               start_gfn = dat_reset_cmma(kvm->arch.gmap->asce, start_gfn);
                        cond_resched();
                } while (start_gfn);
                ret = 0;