From: Stefano Garzarella sgarzare@redhat.com
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@xilinx.com Signed-off-by: Stefano Garzarella sgarzare@redhat.com Message-Id: 20220621151323.190431-1-sgarzare@redhat.com Signed-off-by: Michael S. Tsirkin mst@redhat.com Acked-by: Eugenio Pérez eperezma@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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;