NFS: make nfs_match_client killable

Actually we don't do anything with return value from
    nfs_wait_client_init_complete in nfs_match_client, as a
    consequence if we get a fatal signal and client is not
    fully initialised, we'll loop to "again" label

    This has been proven to cause soft lockups on some scenarios
    (no-carrier but configured network interfaces)

Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Roberto Bergantinos Corpas 2019-04-25 15:36:51 +02:00 committed by Anna Schumaker
parent b422df915c
commit 950a578c61

View File

@ -284,6 +284,7 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat
struct nfs_client *clp;
const struct sockaddr *sap = data->addr;
struct nfs_net *nn = net_generic(data->net, nfs_net_id);
int error;
again:
list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
@ -296,8 +297,10 @@ again:
if (clp->cl_cons_state > NFS_CS_READY) {
refcount_inc(&clp->cl_count);
spin_unlock(&nn->nfs_client_lock);
nfs_wait_client_init_complete(clp);
error = nfs_wait_client_init_complete(clp);
nfs_put_client(clp);
if (error < 0)
return ERR_PTR(error);
spin_lock(&nn->nfs_client_lock);
goto again;
}
@ -407,6 +410,8 @@ struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
clp = nfs_match_client(cl_init);
if (clp) {
spin_unlock(&nn->nfs_client_lock);
if (IS_ERR(clp))
return clp;
if (new)
new->rpc_ops->free_client(new);
return nfs_found_client(cl_init, clp);