[PATCH] s390x/kvm: help valgrind in several places

From: Christian Borntraeger <borntraeger@de.ibm.com>
To: qemu-devel <qemu-devel@nongnu.org>, Cornelia Huck <cohuck@redhat.com>
Cc: Thomas Huth <thuth@redhat.com>,
	Janosch Frank <frankja@linux.ibm.com>,
	David Hildenbrand <david@redhat.com>,
	Halil Pasic <pasic@linux.ibm.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	qemu-s390x <qemu-s390x@nongnu.org>,
	Richard Henderson <rth@twiddle.net>
Subject: [PATCH] s390x/kvm: help valgrind in several places
Date: Tue, 28 Apr 2020 14:31:09 -0400	[thread overview]
Message-ID: <20200428183109.89439-1-borntraeger@de.ibm.com> (raw)

We need some little help in the code to reduce the valgrind noise.
- some designated initializers for the cpu model features and subfunctions
- mark memory as defined for sida memory reads

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 target/s390x/kvm.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
index 69881a0da0..bcd0ee0d14 100644
--- a/target/s390x/kvm.c
+++ b/target/s390x/kvm.c
@@ -52,6 +52,10 @@
 #include "hw/s390x/s390-virtio-hcall.h"
 #include "hw/s390x/pv.h"
 
+#ifdef CONFIG_VALGRIND_H
+#include <valgrind/memcheck.h>
+#endif
+
 #ifndef DEBUG_KVM
 #define DEBUG_KVM  0
 #endif
@@ -875,6 +879,13 @@ int kvm_s390_mem_op_pv(S390CPU *cpu, uint64_t offset, void *hostbuf,
         error_report("KVM_S390_MEM_OP failed: %s", strerror(-ret));
         abort();
     }
+
+#ifdef CONFIG_VALGRIND_H
+    if (!is_write) {
+        VALGRIND_MAKE_MEM_DEFINED(hostbuf, len);
+    }
+#endif
+
     return ret;
 }
 
@@ -2165,7 +2176,7 @@ int kvm_arch_msi_data_to_gsi(uint32_t data)
 
 static int query_cpu_subfunc(S390FeatBitmap features)
 {
-    struct kvm_s390_vm_cpu_subfunc prop;
+    struct kvm_s390_vm_cpu_subfunc prop = {};
     struct kvm_device_attr attr = {
         .group = KVM_S390_VM_CPU_MODEL,
         .attr = KVM_S390_VM_CPU_MACHINE_SUBFUNC,
@@ -2292,7 +2303,7 @@ static int kvm_to_feat[][2] = {
 
 static int query_cpu_feat(S390FeatBitmap features)
 {
-    struct kvm_s390_vm_cpu_feat prop;
+    struct kvm_s390_vm_cpu_feat prop = {};
     struct kvm_device_attr attr = {
         .group = KVM_S390_VM_CPU_MODEL,
         .attr = KVM_S390_VM_CPU_MACHINE_FEAT,
-- 
2.25.1


