Commit f8ad35cb authored by Zhu Lingshan's avatar Zhu Lingshan Committed by Pengyuan Zhao
Browse files

vDPA: !FEATURES_OK should not block querying device config space 

mainline inclusion
from mainline-v6.0-rc1
commit a34bed37
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5WXCZ
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a34bed37fc9d3da319bb75dfbf02a7d3e95e12de



----------------------------------------------------------------------

Users may want to query the config space of a vDPA device,
to choose a appropriate one for a certain guest. This means the
users need to read the config space before FEATURES_OK, and
the existence of config space contents does not depend on
FEATURES_OK.

The spec says:
The device MUST allow reading of any device-specific configuration
field before FEATURES_OK is set by the driver. This includes
fields which are conditional on feature bits, as long as those
feature bits are offered by the device.

Signed-off-by: default avatarZhu Lingshan <lingshan.zhu@intel.com>
Message-Id: <20220722115309.82746-5-lingshan.zhu@intel.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarPengyuan Zhao <zhaopengyuan@hisilicon.com>
parent 8664ed95

drivers/vdpa/vdpa.c

+0 −8
Original line number Diff line number Diff line
@@ -870,17 +870,9 @@ vdpa_dev_config_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, 
{

	u32 device_id;

	void *hdr;

	u8 status;

	int err;



	down_read(&vdev->cf_lock);

	status = vdev->config->get_status(vdev);

	if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) {

		NL_SET_ERR_MSG_MOD(extack, "Features negotiation not completed");

		err = -EAGAIN;

		goto out;

	}



	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags,

			  VDPA_CMD_DEV_CONFIG_GET);

	if (!hdr) {