Stefano Garzarella
2022-Jun-21 15:13 UTC
[PATCH] vdpa_sim_blk: set number of address spaces and virtqueue groups
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 at xilinx.com
Signed-off-by: Stefano Garzarella <sgarzare at redhat.com>
---
drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
index 42d401d43911..03a28def8eee 100644
--- 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 vdpa_mgmt_dev *mdev,
const char *name,
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;
--
2.36.1