[PATCH 6/6] iwpm: crash fix for large connections test

Faisal Latif
2016-02-26T15:18:05Z

During large connection test, there is a crash at wake_up() in the callback as waitq is
not yet initialized. Callback can happen before iwpm_wait_complete_req() is called to
initialize waitq.
To resolve, using signaling semaphore instead of waitq.

Signed-off-by: Mustafa Ismail <mustafa.ismail-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Reviewed-by: Tatyana E Nikolova <tatyana.e.nikolova-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Faisal Latif <faisal.latif-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
drivers/infiniband/core/iwpm_msg.c | 10 +++++-----
drivers/infiniband/core/iwpm_util.c | 14 +++++++-------
drivers/infiniband/core/iwpm_util.h | 2 +-
3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/infiniband/core/iwpm_msg.c b/drivers/infiniband/core/iwpm_msg.c
index c2b4ce6..43e3fa2 100644
--- a/drivers/infiniband/core/iwpm_msg.c
+++ b/drivers/infiniband/core/iwpm_msg.c
@@ -89,7 +89,7 @@ int iwpm_register_pid(struct iwpm_dev_data *pm_msg, u8 nl_client)
if (ret)
goto pid_query_error;
ret = ibnl_put_attr(skb, nlh, IFNAMSIZ,
- pm_msg->if_name, IWPM_NLA_REG_IF_NAME);
+ pm_msg->if_name, IWPM_NLA_REG_IF_NAME);
if (ret)
goto pid_query_error;
ret = ibnl_put_attr(skb, nlh, IWPM_DEVNAME_SIZE,
@@ -394,7 +394,7 @@ register_pid_response_exit:
/* always for found nlmsg_request */
kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
barrier();
- wake_up(&nlmsg_request->waitq);
+ up(&nlmsg_request->sem);
return 0;
}
EXPORT_SYMBOL(iwpm_register_pid_cb);
@@ -463,7 +463,7 @@ add_mapping_response_exit:
/* always for found request */
kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
barrier();
- wake_up(&nlmsg_request->waitq);
+ up(&nlmsg_request->sem);
return 0;
}
EXPORT_SYMBOL(iwpm_add_mapping_cb);
@@ -555,7 +555,7 @@ query_mapping_response_exit:
/* always for found request */
kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
barrier();
- wake_up(&nlmsg_request->waitq);
+ up(&nlmsg_request->sem);
return 0;
}
EXPORT_SYMBOL(iwpm_add_and_query_mapping_cb);
@@ -749,7 +749,7 @@ int iwpm_mapping_error_cb(struct sk_buff *skb, struct netlink_callback *cb)
/* always for found request */
kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
barrier();
- wake_up(&nlmsg_request->waitq);
+ up(&nlmsg_request->sem);
return 0;
}
EXPORT_SYMBOL(iwpm_mapping_error_cb);
diff --git a/drivers/infiniband/core/iwpm_util.c b/drivers/infiniband/core/iwpm_util.c
index 5fb089e..9b2bf2f 100644
--- a/drivers/infiniband/core/iwpm_util.c
+++ b/drivers/infiniband/core/iwpm_util.c
@@ -254,9 +254,9 @@ void iwpm_add_remote_info(struct iwpm_remote_info *rem_info)
}

int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
- struct sockaddr_storage *mapped_rem_addr,
- struct sockaddr_storage *remote_addr,
- u8 nl_client)
+ struct sockaddr_storage *mapped_rem_addr,
+ struct sockaddr_storage *remote_addr,
+ u8 nl_client)
{
struct hlist_node *tmp_hlist_node;
struct hlist_head *hash_bucket_head;
@@ -322,6 +322,8 @@ struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
nlmsg_request->nl_client = nl_client;
nlmsg_request->request_done = 0;
nlmsg_request->err_code = 0;
+ sema_init(&nlmsg_request->sem, 1);
+ down(&nlmsg_request->sem);
return nlmsg_request;
}

@@ -364,11 +366,9 @@ struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq)
int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request)
{
int ret;
- init_waitqueue_head(&nlmsg_request->waitq);

- ret = wait_event_timeout(nlmsg_request->waitq,
- (nlmsg_request->request_done != 0), IWPM_NL_TIMEOUT);
- if (!ret) {
+ ret = down_timeout(&nlmsg_request->sem, IWPM_NL_TIMEOUT);
+ if (ret) {
ret = -EINVAL;
pr_info("%s: Timeout %d sec for netlink request (seq = %u)\n",
__func__, (IWPM_NL_TIMEOUT/HZ), nlmsg_request->nlmsg_seq);
diff --git a/drivers/infiniband/core/iwpm_util.h b/drivers/infiniband/core/iwpm_util.h
index b7b9e19..af1fc14 100644
--- a/drivers/infiniband/core/iwpm_util.h
+++ b/drivers/infiniband/core/iwpm_util.h
@@ -69,7 +69,7 @@ struct iwpm_nlmsg_request {
u8 nl_client;
u8 request_done;
u16 err_code;
- wait_queue_head_t waitq;
+ struct semaphore sem;
struct kref kref;
};