From: Stefano Garzarella <sgarzare@xxxxxxxxxx>
commit 19cd4a5471b8eaa4bd161b0fdb4567f2fc88d809 upstream.
Commit bda324fd037a ("vdpasim: control virtqueue support") added two
new fields (nas, ngroups) to vdpasim_dev_attr, but we forgot to
initialize them for vdpa_sim_blk.
When creating a new vdpa_sim_blk device this causes the kernel
to panic in this way:
$ vdpa dev add mgmtdev vdpasim_blk name blk0
BUG: kernel NULL pointer dereference, address: 0000000000000030
...
RIP: 0010:vhost_iotlb_add_range_ctx+0x41/0x220 [vhost_iotlb]
...
Call Trace:
<TASK>
vhost_iotlb_add_range+0x11/0x800 [vhost_iotlb]
vdpasim_map_range+0x91/0xd0 [vdpa_sim]
vdpasim_alloc_coherent+0x56/0x90 [vdpa_sim]
...
This happens because vdpasim->iommu[0] is not initialized when
dev_attr.nas is 0.
Let's fix this issue by initializing both (nas, ngroups) to 1 for
vdpa_sim_blk.
Fixes: bda324fd037a ("vdpasim: control virtqueue support")
Cc: gautam.dawar@xxxxxxxxxx
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Message-Id: <20220621151323.190431-1-sgarzare@xxxxxxxxxx>
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Acked-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
@@ -34,7 +34,11 @@
#define VDPASIM_BLK_CAPACITY 0x40000
#define VDPASIM_BLK_SIZE_MAX 0x1000
#define VDPASIM_BLK_SEG_MAX 32
+
+/* 1 virtqueue, 1 address space, 1 virtqueue group */
#define VDPASIM_BLK_VQ_NUM 1
+#define VDPASIM_BLK_AS_NUM 1
+#define VDPASIM_BLK_GROUP_NUM 1
static char vdpasim_blk_id[VIRTIO_BLK_ID_BYTES] = "vdpa_blk_sim";
@@ -260,6 +264,8 @@ static int vdpasim_blk_dev_add(struct vd
dev_attr.id = VIRTIO_ID_BLOCK;
dev_attr.supported_features = VDPASIM_BLK_FEATURES;
dev_attr.nvqs = VDPASIM_BLK_VQ_NUM;
+ dev_attr.ngroups = VDPASIM_BLK_GROUP_NUM;
+ dev_attr.nas = VDPASIM_BLK_AS_NUM;
dev_attr.config_size = sizeof(struct virtio_blk_config);
dev_attr.get_config = vdpasim_blk_get_config;
dev_attr.work_fn = vdpasim_blk_work;
