From: Peng He <xnhp0320@gmail.com>
To: dev@dpdk.org
Cc: maxime.coquelin@redhat.com
Subject: [dpdk-dev] [PATCH] lib/librte_vhost: fix vid allocation race
Date: Fri, 29 Jan 2021 15:35:47 +0800 [thread overview]
Message-ID: <20210129073547.80108-1-hepeng.0320@bytedance.com> (raw)
From: "chenwei.0515" <chenwei.0515@bytedance.com>
vhost_new_devcie might be called in different threads at the same time.
thread 1(config thread)
rte_vhost_driver_start
->vhost_user_start_client
->vhost_user_add_connection
-> vhost_new_device
thread 2(vhost-events)
vhost_user_read_cb
->vhost_user_msg_handler (return value < 0)
-> vhost_user_start_client
-> vhost_new_device
So there could be a case that a same vid has been allocated twice, or
some vid might be lost in DPDK lib however still held by the upper
applications.
Reported-by: Peng He <hepeng.0320@bytedance.com>
Signed-off-by: Fei Chen <chenwei.0515@bytedance.com>
Reviewed-by: Zhihong Wang <wangzhihong.wzh@bytedance.com>
---
lib/librte_vhost/vhost.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index efb136edd1..db11d293d2 100644
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -26,6 +26,7 @@
#include "vhost_user.h"
struct virtio_net *vhost_devices[MAX_VHOST_DEVICE];
+pthread_mutex_t vhost_dev_lock = PTHREAD_MUTEX_INITIALIZER;
/* Called with iotlb_lock read-locked */
uint64_t
@@ -645,6 +646,7 @@ vhost_new_device(void)
struct virtio_net *dev;
int i;
+ pthread_mutex_lock(&vhost_dev_lock);
for (i = 0; i < MAX_VHOST_DEVICE; i++) {
if (vhost_devices[i] == NULL)
break;
@@ -653,6 +655,7 @@ vhost_new_device(void)
if (i == MAX_VHOST_DEVICE) {
VHOST_LOG_CONFIG(ERR,
"Failed to find a free slot for new device.\n");
+ pthread_mutex_unlock(&vhost_dev_lock);
return -1;
}
@@ -660,10 +663,13 @@ vhost_new_device(void)
if (dev == NULL) {
VHOST_LOG_CONFIG(ERR,
"Failed to allocate memory for new dev.\n");
+ pthread_mutex_unlock(&vhost_dev_lock);
return -1;
}
vhost_devices[i] = dev;
+ pthread_mutex_unlock(&vhost_dev_lock);
+
dev->vid = i;
dev->flags = VIRTIO_DEV_BUILTIN_VIRTIO_NET;
dev->slave_req_fd = -1;
--
2.23.0
next reply other threads:[~2021-01-29 9:45 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-29 7:35 Peng He [this message]
2021-02-01 6:27 ` Xia, Chenbo
2021-02-01 8:48 ` [dpdk-dev] [PATCH v2] vhost: " Peng He
2021-02-03 2:44 ` Xia, Chenbo
2021-02-03 17:21 ` Maxime Coquelin
2021-02-01 8:53 ` [dpdk-dev] [PATCH] lib/librte_vhost: " 贺鹏
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