On Wed, Jan 23, 2019 at 11:00:24PM -0800, Qian Lu wrote: > From: Scott Mayhew <smayhew@xxxxxxxxxx> > > The following deadlock can occur between a process waiting for a client > to initialize in while walking the client list during nfsv4 server trunking > detection and another process waiting for the nfs_clid_init_mutex so it > can initialize that client: > > Process 1 Process 2 > --------- --------- > spin_lock(&nn->nfs_client_lock); > list_add_tail(&CLIENTA->cl_share_link, > &nn->nfs_client_list); > spin_unlock(&nn->nfs_client_lock); > spin_lock(&nn->nfs_client_lock); > list_add_tail(&CLIENTB->cl_share_link, > &nn->nfs_client_list); > spin_unlock(&nn->nfs_client_lock); > mutex_lock(&nfs_clid_init_mutex); > nfs41_walk_client_list(clp, result, cred); > nfs_wait_client_init_complete(CLIENTA); > (waiting for nfs_clid_init_mutex) > > Make sure nfs_match_client() only evaluates clients that have completed > initialization in order to prevent that deadlock. > > This patch also fixes v4.0 trunking behavior by not marking the client > NFS_CS_READY until the clientid has been confirmed. > > Signed-off-by: Scott Mayhew <smayhew@xxxxxxxxxx> > Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> > Signed-off-by: Qian Lu <luqia@xxxxxxxxxx> > --- > fs/nfs/client.c | 11 +++++++++++ > fs/nfs/nfs4client.c | 17 +++++++++++++---- > 2 files changed, 24 insertions(+), 4 deletions(-) You forgot to mention the sha1 of the commit :( I dug it up this time... greg k-h
