From: Leon Romanovsky <leonro@nvidia.com>
Devlink reload was implemented as a special command which does _SET_
operation, but doesn't take devlink->lock, while recursive devlink
calls that were part of .reload_up()/.reload_down() sequence took it.
This fragile flow was possible due to holding a big devlink lock
(devlink_mutex), which effectively stopped all devlink activities,
even unrelated to reloaded devlink.
So let's make sure that devlink reload behaves as other commands.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
net/core/devlink.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/core/devlink.c b/net/core/devlink.c
index 60af6a3fc130..32d274bfd049 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -8771,7 +8771,6 @@ static const struct genl_small_ops devlink_nl_ops[] = {
.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
.doit = devlink_nl_cmd_reload,
.flags = GENL_ADMIN_PERM,
- .internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
},
{
.cmd = DEVLINK_CMD_PARAM_GET,@@ -11462,6 +11461,7 @@ static void __net_exit devlink_pernet_pre_exit(struct net *net)
if (!net_eq(devlink_net(devlink), net))
goto retry;
+ mutex_lock(&devlink->lock);
WARN_ON(!(devlink->features & DEVLINK_F_RELOAD));
err = devlink_reload(devlink, &init_net,
DEVLINK_RELOAD_ACTION_DRIVER_REINIT,
@@ -11469,6 +11469,7 @@ static void __net_exit devlink_pernet_pre_exit(struct net *net)
&actions_performed, NULL);
if (err && err != -EOPNOTSUPP)
pr_warn("Failed to reload devlink instance into init_net\n");
+ mutex_unlock(&devlink->lock);
retry:
devlink_put(devlink);
}--
2.33.1