Covscan reported:
2. dpdk-21.11/lib/vhost/socket.c:852: lock_acquire: Calling function
"pthread_mutex_lock" acquires lock "vhost_user.mutex".
23. dpdk-21.11/lib/vhost/socket.c:955: sleep: Call to
"vhost_user_reconnect_init" might sleep while holding lock
"vhost_user.mutex".
# 953| vsocket->reconnect =
!(flags & RTE_VHOST_USER_NO_RECONNECT);
# 954| if (vsocket->reconnect && reconn_tid == 0) {
# 955|-> if (vhost_user_reconnect_init() != 0)
# 956| goto out_mutex;
# 957| }
The reason for this warning is that vhost_user_reconnect_init() creates a
ctrl thread and calls nanosleep waiting for this thread to be ready,
while vhost_user.mutex is taken.
Move the call to vhost_user_reconnect_init() out of this mutex.
While at it, a pthread_t value should be considered opaque.
Instead of relying reconn_tid == 0, use an internal flag in
vhost_user_reconnect_init().
Coverity issue: 373686
Bugzilla ID: 981
Fixes: e623e0c6d8a5 ("vhost: add reconnect ability")
Cc: sta...@dpdk.org
Signed-off-by: David Marchand <david.march...@redhat.com>
---
Changes since v1:
- moved reconn_tid in vhost_user_reconnect_init as this
variable is not used anywhere else,
---
lib/vhost/socket.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/lib/vhost/socket.c b/lib/vhost/socket.c
index 669c322e12..00a912c59e 100644
--- a/lib/vhost/socket.c
+++ b/lib/vhost/socket.c
@@ -427,7 +427,6 @@ struct vhost_user_reconnect_list {
};
static struct vhost_user_reconnect_list reconn_list;
-static pthread_t reconn_tid;
static int
vhost_user_connect_nonblock(char *path, int fd, struct sockaddr *un, size_t sz)
@@ -498,8 +497,13 @@ vhost_user_client_reconnect(void *arg __rte_unused)
static int
vhost_user_reconnect_init(void)
{
+ static bool reconn_init_done;
+ static pthread_t reconn_tid;
int ret;
+ if (reconn_init_done)
+ return 0;
+
ret = pthread_mutex_init(&reconn_list.mutex, NULL);
if (ret < 0) {
VHOST_LOG_CONFIG("thread", ERR, "%s: failed to initialize
mutex\n", __func__);
@@ -515,6 +519,8 @@ vhost_user_reconnect_init(void)
VHOST_LOG_CONFIG("thread", ERR,
"%s: failed to destroy reconnect mutex\n",
__func__);
+ } else {
+ reconn_init_done = true;
}
return ret;
@@ -866,6 +872,11 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
if (!path)
return -1;
+ if ((flags & RTE_VHOST_USER_CLIENT) != 0 &&
+ (flags & RTE_VHOST_USER_NO_RECONNECT) == 0 &&
+ vhost_user_reconnect_init() != 0)
+ return -1;
+
pthread_mutex_lock(&vhost_user.mutex);
if (vhost_user.vsocket_cnt == MAX_VHOST_SOCKET) {
@@ -961,11 +972,7 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
}
if ((flags & RTE_VHOST_USER_CLIENT) != 0) {
- vsocket->reconnect = !(flags & RTE_VHOST_USER_NO_RECONNECT);
- if (vsocket->reconnect && reconn_tid == 0) {
- if (vhost_user_reconnect_init() != 0)
- goto out_mutex;
- }
+ vsocket->reconnect = (flags & RTE_VHOST_USER_NO_RECONNECT) == 0;
} else {
vsocket->is_server = true;
}
--
2.40.0
