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hv_netvsc: Register VF in netvsc_probe if NET_DEVICE_REGISTER missed

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If hv_netvsc driver is unloaded and reloaded, the NET_DEVICE_REGISTER
handler cannot perform VF register successfully as the register call
is received before netvsc_probe is finished. This is because we
register register_netdevice_notifier() very early( even before
vmbus_driver_register()).
To fix this, we try to register each such matching VF( if it is visible
as a netdevice) at the end of netvsc_probe.

Cc: stable@vger.kernel.org
Fixes: 8552085646 ("hv_netvsc: Fix race of register_netdevice_notifier and VF register")
Suggested-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Shradha Gupta 2024-02-01 20:40:38 -08:00 committed by David S. Miller
parent b09b58e31b
commit 9cae43da98
1 changed files with 62 additions and 20 deletions
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80
drivers/net/hyperv/netvsc_drv.c
View File

@ -42,6 +42,10 @@
#define LINKCHANGE_INT (2 * HZ)
#define VF_TAKEOVER_INT (HZ / 10)
/* Macros to define the context of vf registration */
#define VF_REG_IN_PROBE 1
#define VF_REG_IN_NOTIFIER 2
static unsigned int ring_size __ro_after_init = 128;
module_param(ring_size, uint, 0444);
MODULE_PARM_DESC(ring_size, "Ring buffer size (# of 4K pages)");
@ -2185,7 +2189,7 @@ static rx_handler_result_t netvsc_vf_handle_frame(struct sk_buff **pskb)
}
static int netvsc_vf_join(struct net_device *vf_netdev,
struct net_device *ndev)
struct net_device *ndev, int context)
{
struct net_device_context *ndev_ctx = netdev_priv(ndev);
int ret;
@ -2208,6 +2212,10 @@ static int netvsc_vf_join(struct net_device *vf_netdev,
goto upper_link_failed;
}
/* If this registration is called from probe context vf_takeover
* is taken care of later in probe itself.
*/
if (context == VF_REG_IN_NOTIFIER)
schedule_delayed_work(&ndev_ctx->vf_takeover, VF_TAKEOVER_INT);
call_netdevice_notifiers(NETDEV_JOIN, vf_netdev);
@ -2346,7 +2354,7 @@ static int netvsc_prepare_bonding(struct net_device *vf_netdev)
return NOTIFY_DONE;
}
static int netvsc_register_vf(struct net_device *vf_netdev)
static int netvsc_register_vf(struct net_device *vf_netdev, int context)
{
struct net_device_context *net_device_ctx;
struct netvsc_device *netvsc_dev;
@ -2386,7 +2394,7 @@ static int netvsc_register_vf(struct net_device *vf_netdev)
netdev_info(ndev, "VF registering: %s\n", vf_netdev->name);
if (netvsc_vf_join(vf_netdev, ndev) != 0)
if (netvsc_vf_join(vf_netdev, ndev, context) != 0)
return NOTIFY_DONE;
dev_hold(vf_netdev);
@ -2484,10 +2492,31 @@ static int netvsc_unregister_vf(struct net_device *vf_netdev)
return NOTIFY_OK;
}
static int check_dev_is_matching_vf(struct net_device *event_ndev)
{
/* Skip NetVSC interfaces */
if (event_ndev->netdev_ops == &device_ops)
return -ENODEV;
/* Avoid non-Ethernet type devices */
if (event_ndev->type != ARPHRD_ETHER)
return -ENODEV;
/* Avoid Vlan dev with same MAC registering as VF */
if (is_vlan_dev(event_ndev))
return -ENODEV;
/* Avoid Bonding master dev with same MAC registering as VF */
if (netif_is_bond_master(event_ndev))
return -ENODEV;
return 0;
}
static int netvsc_probe(struct hv_device *dev,
const struct hv_vmbus_device_id *dev_id)
{
struct net_device *net = NULL;
struct net_device *net = NULL, *vf_netdev;
struct net_device_context *net_device_ctx;
struct netvsc_device_info *device_info = NULL;
struct netvsc_device *nvdev;
@ -2599,6 +2628,30 @@ static int netvsc_probe(struct hv_device *dev,
}
list_add(&net_device_ctx->list, &netvsc_dev_list);
/* When the hv_netvsc driver is unloaded and reloaded, the
* NET_DEVICE_REGISTER for the vf device is replayed before probe
* is complete. This is because register_netdevice_notifier() gets
* registered before vmbus_driver_register() so that callback func
* is set before probe and we don't miss events like NETDEV_POST_INIT
* So, in this section we try to register the matching vf device that
* is present as a netdevice, knowing that its register call is not
* processed in the netvsc_netdev_notifier(as probing is progress and
* get_netvsc_byslot fails).
*/
for_each_netdev(dev_net(net), vf_netdev) {
ret = check_dev_is_matching_vf(vf_netdev);
if (ret != 0)
continue;
if (net != get_netvsc_byslot(vf_netdev))
continue;
netvsc_prepare_bonding(vf_netdev);
netvsc_register_vf(vf_netdev, VF_REG_IN_PROBE);
__netvsc_vf_setup(net, vf_netdev);
break;
}
rtnl_unlock();
netvsc_devinfo_put(device_info);
@ -2754,28 +2807,17 @@ static int netvsc_netdev_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
int ret = 0;
/* Skip our own events */
if (event_dev->netdev_ops == &device_ops)
return NOTIFY_DONE;
/* Avoid non-Ethernet type devices */
if (event_dev->type != ARPHRD_ETHER)
return NOTIFY_DONE;
/* Avoid Vlan dev with same MAC registering as VF */
if (is_vlan_dev(event_dev))
return NOTIFY_DONE;
/* Avoid Bonding master dev with same MAC registering as VF */
if (netif_is_bond_master(event_dev))
ret = check_dev_is_matching_vf(event_dev);
if (ret != 0)
return NOTIFY_DONE;
switch (event) {
case NETDEV_POST_INIT:
return netvsc_prepare_bonding(event_dev);
case NETDEV_REGISTER:
return netvsc_register_vf(event_dev);
return netvsc_register_vf(event_dev, VF_REG_IN_NOTIFIER);
case NETDEV_UNREGISTER:
return netvsc_unregister_vf(event_dev);
case NETDEV_UP: