mei: do not run reset flow from the interrupt thread
This fixes a potential deadlock in case of a firmware
initiated reset
mei_reset has a dialog with the interrupt thread hence
it has to be run from an another work item
Most of the mei_resets were called from mei_hbm_dispatch
which is called in interrupt thread context so this
function underwent major revamp. The error code is
propagated to the interrupt thread and if needed
the reset is scheduled from there.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
index 9b3a0fb..8109b9a 100644
--- a/drivers/misc/mei/hbm.c
+++ b/drivers/misc/mei/hbm.c
@@ -28,9 +28,9 @@
*
* @dev: the device structure
*
- * returns none.
+ * returns 0 on success -ENOMEM on allocation failure
*/
-static void mei_hbm_me_cl_allocate(struct mei_device *dev)
+static int mei_hbm_me_cl_allocate(struct mei_device *dev)
{
struct mei_me_client *clients;
int b;
@@ -44,7 +44,7 @@
dev->me_clients_num++;
if (dev->me_clients_num == 0)
- return;
+ return 0;
kfree(dev->me_clients);
dev->me_clients = NULL;
@@ -56,12 +56,10 @@
sizeof(struct mei_me_client), GFP_KERNEL);
if (!clients) {
dev_err(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
- dev->dev_state = MEI_DEV_RESETTING;
- mei_reset(dev, 1);
- return;
+ return -ENOMEM;
}
dev->me_clients = clients;
- return;
+ return 0;
}
/**
@@ -137,7 +135,7 @@
mutex_unlock(&dev->device_lock);
ret = wait_event_interruptible_timeout(dev->wait_recvd_msg,
dev->hbm_state == MEI_HBM_IDLE ||
- dev->hbm_state > MEI_HBM_START,
+ dev->hbm_state >= MEI_HBM_STARTED,
mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
mutex_lock(&dev->device_lock);
@@ -153,12 +151,15 @@
* mei_hbm_start_req - sends start request message.
*
* @dev: the device structure
+ *
+ * returns 0 on success and < 0 on failure
*/
int mei_hbm_start_req(struct mei_device *dev)
{
struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
struct hbm_host_version_request *start_req;
const size_t len = sizeof(struct hbm_host_version_request);
+ int ret;
mei_hbm_hdr(mei_hdr, len);
@@ -170,12 +171,13 @@
start_req->host_version.minor_version = HBM_MINOR_VERSION;
dev->hbm_state = MEI_HBM_IDLE;
- if (mei_write_message(dev, mei_hdr, dev->wr_msg.data)) {
- dev_err(&dev->pdev->dev, "version message write failed\n");
- dev->dev_state = MEI_DEV_RESETTING;
- mei_reset(dev, 1);
- return -EIO;
+ ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+ if (ret) {
+ dev_err(&dev->pdev->dev, "version message write failed: ret = %d\n",
+ ret);
+ return ret;
}
+
dev->hbm_state = MEI_HBM_START;
dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
return 0;
@@ -186,13 +188,15 @@
*
* @dev: the device structure
*
- * returns none.
+ * returns 0 on success and < 0 on failure
*/
-static void mei_hbm_enum_clients_req(struct mei_device *dev)
+static int mei_hbm_enum_clients_req(struct mei_device *dev)
{
struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
struct hbm_host_enum_request *enum_req;
const size_t len = sizeof(struct hbm_host_enum_request);
+ int ret;
+
/* enumerate clients */
mei_hbm_hdr(mei_hdr, len);
@@ -200,14 +204,15 @@
memset(enum_req, 0, len);
enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
- if (mei_write_message(dev, mei_hdr, dev->wr_msg.data)) {
- dev->dev_state = MEI_DEV_RESETTING;
- dev_err(&dev->pdev->dev, "enumeration request write failed.\n");
- mei_reset(dev, 1);
+ ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+ if (ret) {
+ dev_err(&dev->pdev->dev, "enumeration request write failed: ret = %d.\n",
+ ret);
+ return ret;
}
dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
- return;
+ return 0;
}
/**
@@ -215,7 +220,7 @@
*
* @dev: the device structure
*
- * returns none.
+ * returns 0 on success and < 0 on failure
*/
static int mei_hbm_prop_req(struct mei_device *dev)
@@ -226,7 +231,7 @@
const size_t len = sizeof(struct hbm_props_request);
unsigned long next_client_index;
unsigned long client_num;
-
+ int ret;
client_num = dev->me_client_presentation_num;
@@ -253,12 +258,11 @@
prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
prop_req->address = next_client_index;
- if (mei_write_message(dev, mei_hdr, dev->wr_msg.data)) {
- dev->dev_state = MEI_DEV_RESETTING;
- dev_err(&dev->pdev->dev, "properties request write failed\n");
- mei_reset(dev, 1);
-
- return -EIO;
+ ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
+ if (ret) {
+ dev_err(&dev->pdev->dev, "properties request write failed: ret = %d\n",
+ ret);
+ return ret;
}
dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
@@ -559,8 +563,10 @@
*
* @dev: the device structure
* @mei_hdr: header of bus message
+ *
+ * returns 0 on success and < 0 on failure
*/
-void mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
+int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
{
struct mei_bus_message *mei_msg;
struct mei_me_client *me_client;
@@ -579,6 +585,10 @@
switch (mei_msg->hbm_cmd) {
case HOST_START_RES_CMD:
+ dev_dbg(&dev->pdev->dev, "hbm: start: response message received.\n");
+
+ dev->init_clients_timer = 0;
+
version_res = (struct hbm_host_version_response *)mei_msg;
dev_dbg(&dev->pdev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
@@ -597,73 +607,89 @@
}
if (!mei_hbm_version_is_supported(dev)) {
- dev_warn(&dev->pdev->dev, "hbm version mismatch: stopping the driver.\n");
+ dev_warn(&dev->pdev->dev, "hbm: start: version mismatch - stopping the driver.\n");
- dev->hbm_state = MEI_HBM_STOP;
+ dev->hbm_state = MEI_HBM_STOPPED;
mei_hbm_stop_req_prepare(dev, &dev->wr_msg.hdr,
dev->wr_msg.data);
- mei_write_message(dev, &dev->wr_msg.hdr,
- dev->wr_msg.data);
-
- return;
+ if (mei_write_message(dev, &dev->wr_msg.hdr,
+ dev->wr_msg.data)) {
+ dev_err(&dev->pdev->dev, "hbm: start: failed to send stop request\n");
+ return -EIO;
+ }
+ break;
}
- if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
- dev->hbm_state == MEI_HBM_START) {
- dev->init_clients_timer = 0;
- mei_hbm_enum_clients_req(dev);
- } else {
- dev_err(&dev->pdev->dev, "reset: wrong host start response\n");
- mei_reset(dev, 1);
- return;
+ if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+ dev->hbm_state != MEI_HBM_START) {
+ dev_err(&dev->pdev->dev, "hbm: start: state mismatch, [%d, %d]\n",
+ dev->dev_state, dev->hbm_state);
+ return -EPROTO;
+ }
+
+ dev->hbm_state = MEI_HBM_STARTED;
+
+ if (mei_hbm_enum_clients_req(dev)) {
+ dev_err(&dev->pdev->dev, "hbm: start: failed to send enumeration request\n");
+ return -EIO;
}
wake_up_interruptible(&dev->wait_recvd_msg);
- dev_dbg(&dev->pdev->dev, "host start response message received.\n");
break;
case CLIENT_CONNECT_RES_CMD:
+ dev_dbg(&dev->pdev->dev, "hbm: client connect response: message received.\n");
+
connect_res = (struct hbm_client_connect_response *) mei_msg;
mei_hbm_cl_connect_res(dev, connect_res);
- dev_dbg(&dev->pdev->dev, "client connect response message received.\n");
wake_up(&dev->wait_recvd_msg);
break;
case CLIENT_DISCONNECT_RES_CMD:
+ dev_dbg(&dev->pdev->dev, "hbm: client disconnect response: message received.\n");
+
disconnect_res = (struct hbm_client_connect_response *) mei_msg;
mei_hbm_cl_disconnect_res(dev, disconnect_res);
- dev_dbg(&dev->pdev->dev, "client disconnect response message received.\n");
wake_up(&dev->wait_recvd_msg);
break;
case MEI_FLOW_CONTROL_CMD:
+ dev_dbg(&dev->pdev->dev, "hbm: client flow control response: message received.\n");
+
flow_control = (struct hbm_flow_control *) mei_msg;
mei_hbm_cl_flow_control_res(dev, flow_control);
- dev_dbg(&dev->pdev->dev, "client flow control response message received.\n");
break;
case HOST_CLIENT_PROPERTIES_RES_CMD:
+ dev_dbg(&dev->pdev->dev, "hbm: properties response: message received.\n");
+
+ dev->init_clients_timer = 0;
+
+ if (dev->me_clients == NULL) {
+ dev_err(&dev->pdev->dev, "hbm: properties response: mei_clients not allocated\n");
+ return -EPROTO;
+ }
+
props_res = (struct hbm_props_response *)mei_msg;
me_client = &dev->me_clients[dev->me_client_presentation_num];
- if (props_res->status || !dev->me_clients) {
- dev_err(&dev->pdev->dev, "reset: properties response hbm wrong status.\n");
- mei_reset(dev, 1);
- return;
+ if (props_res->status) {
+ dev_err(&dev->pdev->dev, "hbm: properties response: wrong status = %d\n",
+ props_res->status);
+ return -EPROTO;
}
if (me_client->client_id != props_res->address) {
- dev_err(&dev->pdev->dev, "reset: host properties response address mismatch\n");
- mei_reset(dev, 1);
- return;
+ dev_err(&dev->pdev->dev, "hbm: properties response: address mismatch %d ?= %d\n",
+ me_client->client_id, props_res->address);
+ return -EPROTO;
}
if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
- dev_err(&dev->pdev->dev, "reset: unexpected properties response\n");
- mei_reset(dev, 1);
-
- return;
+ dev_err(&dev->pdev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
+ dev->dev_state, dev->hbm_state);
+ return -EPROTO;
}
me_client->props = props_res->client_properties;
@@ -671,49 +697,70 @@
dev->me_client_presentation_num++;
/* request property for the next client */
- mei_hbm_prop_req(dev);
+ if (mei_hbm_prop_req(dev))
+ return -EIO;
break;
case HOST_ENUM_RES_CMD:
+ dev_dbg(&dev->pdev->dev, "hbm: enumeration response: message received\n");
+
+ dev->init_clients_timer = 0;
+
enum_res = (struct hbm_host_enum_response *) mei_msg;
BUILD_BUG_ON(sizeof(dev->me_clients_map)
< sizeof(enum_res->valid_addresses));
memcpy(dev->me_clients_map, enum_res->valid_addresses,
sizeof(enum_res->valid_addresses));
- if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
- dev->hbm_state == MEI_HBM_ENUM_CLIENTS) {
- dev->init_clients_timer = 0;
- mei_hbm_me_cl_allocate(dev);
- dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
- /* first property reqeust */
- mei_hbm_prop_req(dev);
- } else {
- dev_err(&dev->pdev->dev, "reset: unexpected enumeration response hbm.\n");
- mei_reset(dev, 1);
- return;
+ if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
+ dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
+ dev_err(&dev->pdev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
+ dev->dev_state, dev->hbm_state);
+ return -EPROTO;
}
+
+ if (mei_hbm_me_cl_allocate(dev)) {
+ dev_err(&dev->pdev->dev, "hbm: enumeration response: cannot allocate clients array\n");
+ return -ENOMEM;
+ }
+
+ dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
+
+ /* first property request */
+ if (mei_hbm_prop_req(dev))
+ return -EIO;
+
break;
case HOST_STOP_RES_CMD:
+ dev_dbg(&dev->pdev->dev, "hbm: stop response: message received\n");
- if (dev->hbm_state != MEI_HBM_STOP)
- dev_err(&dev->pdev->dev, "unexpected stop response hbm.\n");
+ dev->init_clients_timer = 0;
+
+ if (dev->hbm_state != MEI_HBM_STOPPED) {
+ dev_err(&dev->pdev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
+ dev->dev_state, dev->hbm_state);
+ return -EPROTO;
+ }
+
dev->dev_state = MEI_DEV_DISABLED;
- dev_info(&dev->pdev->dev, "reset: FW stop response.\n");
- mei_reset(dev, 1);
+ dev_info(&dev->pdev->dev, "hbm: stop response: resetting.\n");
+ /* force the reset */
+ return -EPROTO;
break;
case CLIENT_DISCONNECT_REQ_CMD:
- /* search for client */
+ dev_dbg(&dev->pdev->dev, "hbm: disconnect request: message received\n");
+
disconnect_req = (struct hbm_client_connect_request *)mei_msg;
mei_hbm_fw_disconnect_req(dev, disconnect_req);
break;
case ME_STOP_REQ_CMD:
+ dev_dbg(&dev->pdev->dev, "hbm: stop request: message received\n");
- dev->hbm_state = MEI_HBM_STOP;
+ dev->hbm_state = MEI_HBM_STOPPED;
mei_hbm_stop_req_prepare(dev, &dev->wr_ext_msg.hdr,
dev->wr_ext_msg.data);
break;
@@ -722,5 +769,6 @@
break;
}
+ return 0;
}