[GIT PULL 33/42] KVM: s390: pv: clear the state without memset

Claudio Imbrenda
2022-07-21T16:14:26Z

Do not use memset to clean the whole struct kvm_s390_pv; instead,
explicitly clear the fields that need to be cleared.

Upcoming patches will introduce new fields in the struct kvm_s390_pv
that will not need to be cleared.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20220628135619.32410-8-imbrenda@linux.ibm.com
Message-Id: <20220628135619.32410-8-imbrenda@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
arch/s390/kvm/pv.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c
index 59e0d5399113..d18c5ccfa5dc 100644
--- a/arch/s390/kvm/pv.c
+++ b/arch/s390/kvm/pv.c
@@ -17,6 +17,14 @@
#include <linux/sched/mm.h>
#include "kvm-s390.h"

+static void kvm_s390_clear_pv_state(struct kvm *kvm)
+{
+ kvm->arch.pv.handle = 0;
+ kvm->arch.pv.guest_len = 0;
+ kvm->arch.pv.stor_base = 0;
+ kvm->arch.pv.stor_var = NULL;
+}
+
int kvm_s390_pv_destroy_cpu(struct kvm_vcpu *vcpu, u16 *rc, u16 *rrc)
{
int cc;
@@ -111,7 +119,7 @@ static void kvm_s390_pv_dealloc_vm(struct kvm *kvm)
vfree(kvm->arch.pv.stor_var);
free_pages(kvm->arch.pv.stor_base,
get_order(uv_info.guest_base_stor_len));
- memset(&kvm->arch.pv, 0, sizeof(kvm->arch.pv));
+ kvm_s390_clear_pv_state(kvm);
}

static int kvm_s390_pv_alloc_vm(struct kvm *kvm)
--
2.36.1