On Fri, 2024-09-06 at 00:57 +0000, Oleksandr Tymoshenko wrote: > nfs41_init_clientid does not signal a failure condition from > nfs4_proc_exchange_id and nfs4_proc_create_session to a client which > may > lead to mount syscall indefinitely blocked in the following stack > trace: > nfs_wait_client_init_complete > nfs41_discover_server_trunking > nfs4_discover_server_trunking > nfs4_init_client > nfs4_set_client > nfs4_create_server > nfs4_try_get_tree > vfs_get_tree > do_new_mount > __se_sys_mount > > and the client stuck in uninitialized state. > > In addition to this all subsequent mount calls would also get blocked > in > nfs_match_client waiting for the uninitialized client to finish > initialization: > nfs_wait_client_init_complete > nfs_match_client > nfs_get_client > nfs4_set_client > nfs4_create_server > nfs4_try_get_tree > vfs_get_tree > do_new_mount > __se_sys_mount > > To avoid this situation propagate error condition to the mount thread > and let mount syscall fail properly. > > Signed-off-by: Oleksandr Tymoshenko <ovt@xxxxxxxxxx> > --- > fs/nfs/nfs4state.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c > index 877f682b45f2..54ad3440ad2b 100644 > --- a/fs/nfs/nfs4state.c > +++ b/fs/nfs/nfs4state.c > @@ -335,8 +335,8 @@ int nfs41_init_clientid(struct nfs_client *clp, > const struct cred *cred) > if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R)) > nfs4_state_start_reclaim_reboot(clp); > nfs41_finish_session_reset(clp); > - nfs_mark_client_ready(clp, NFS_CS_READY); > out: > + nfs_mark_client_ready(clp, status == 0 ? NFS_CS_READY : > status); > return status; > } NACK. This will break all sorts of recovery scenarios, because it doesn't distinguish between an initial 'mount' and a server reboot recovery situation. Even in the case where we are in the initial mount, it also doesn't distinguish between transient errors such as NFS4ERR_DELAY or reboot errors such as NFS4ERR_STALE_CLIENTID, etc. Exactly what is the scenario that is causing your hang? Let's try to address that with a more targeted fix. -- Trond Myklebust Linux NFS client maintainer, Hammerspace trond.myklebust@xxxxxxxxxxxxxxx
