diff mbox

[12/12] s390x: initialize virtio dev region

Message ID 1321290400-32717-13-git-send-email-agraf@suse.de
State New
Headers show

Commit Message

Alexander Graf Nov. 14, 2011, 5:06 p.m. UTC 
When running the s390x virtio machine we can potentially use uninitialized
memory for the virtio device backing ram. That can lead to weird breakge.

So let's better initialize it to 0 properly.

Reported-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

---

v1 -> v2:

  - use target_phys_addr_t
---
 hw/s390-virtio.c |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)
diff mbox

Patch

diff --git a/hw/s390-virtio.c b/hw/s390-virtio.c
index 37945d5..61b67e8 100644
--- a/hw/s390-virtio.c
+++ b/hw/s390-virtio.c
@@ -165,6 +165,9 @@  static void s390_init(ram_addr_t my_ram_size,
     ram_addr_t initrd_size = 0;
     int shift = 0;
     uint8_t *storage_keys;
+    void *virtio_region;
+    target_phys_addr_t virtio_region_len;
+    target_phys_addr_t virtio_region_start;
     int i;
 
     /* s390x ram size detection needs a 16bit multiplier + an increment. So
@@ -184,6 +187,15 @@  static void s390_init(ram_addr_t my_ram_size,
     memory_region_init_ram(ram, NULL, "s390.ram", my_ram_size);
     memory_region_add_subregion(sysmem, 0, ram);
 
+    /* clear virtio region */
+    virtio_region_len = my_ram_size - ram_size;
+    virtio_region_start = ram_size;
+    virtio_region = cpu_physical_memory_map(virtio_region_start,
+                                            &virtio_region_len, true);
+    memset(virtio_region, 0, virtio_region_len);
+    cpu_physical_memory_unmap(virtio_region, virtio_region_len, 1,
+                              virtio_region_len);
+
     /* allocate storage keys */
     storage_keys = g_malloc0(my_ram_size / TARGET_PAGE_SIZE);