Hi Sasha, if you take this one, you'll need the fix for it:
c260121a97a3 ("NFS: Fix a double unlock from nfs_match,get_client")
I didn't see this fix go through my inbox for your stable tree, so apologies if maybe I missed it.
Looks like you are also applying this one to 4.19 and 4.14, -- I'll just reply once here.
Ben
On 22 May 2019, at 15:15, Sasha Levin wrote:
From: Roberto Bergantinos Corpas rbergant@redhat.com
[ Upstream commit 950a578c6128c2886e295b9c7ecb0b6b22fcc92b ]
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 Signed-off-by: Sasha Levin sashal@kernel.org
fs/nfs/client.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 90d71fda65cec..350cfa561e0e8 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -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 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat 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);-- 2.20.1