From 54ac471c83aff6b1e068eb8029c797dc68a76e89 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Wed, 23 May 2012 13:26:10 -0400 Subject: NFS: Add memory barriers to the nfs_client->cl_cons_state initialisation Ensure that a process that uses the nfs_client->cl_cons_state test for whether the initialisation process is finished does not read stale data. Signed-off-by: Trond Myklebust --- fs/nfs/client.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/nfs/client.c') diff --git a/fs/nfs/client.c b/fs/nfs/client.c index d35664287e1..a50bdfbbc42 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -459,6 +459,8 @@ static bool nfs4_cb_match_client(const struct sockaddr *addr, clp->cl_cons_state == NFS_CS_SESSION_INITING)) return false; + smp_rmb(); + /* Match the version and minorversion */ if (clp->rpc_ops->version != 4 || clp->cl_minorversion != minorversion) @@ -539,6 +541,8 @@ nfs_found_client(const struct nfs_client_initdata *cl_init, return ERR_PTR(error); } + smp_rmb(); + BUG_ON(clp->cl_cons_state != NFS_CS_READY); dprintk("<-- %s found nfs_client %p for %s\n", @@ -597,6 +601,7 @@ nfs_get_client(const struct nfs_client_initdata *cl_init, */ void nfs_mark_client_ready(struct nfs_client *clp, int state) { + smp_wmb(); clp->cl_cons_state = state; wake_up_all(&nfs_client_active_wq); } -- cgit v1.2.3