Crashes have been observed for NFSv4.1 mounts when the system

is being shut down which were caused by the nfscbd_pool being
destroyed before the backchannel is disabled. This patch is
believed to fix the problem, by simply avoiding ever destroying
the nfscbd_pool. Since the NFS client module cannot be unloaded,
this should not cause a memory leak.

MFC after:	2 weeks

1 files changed, 9 insertions, 11 deletions

diff --git a/sys/fs/nfsclient/nfs_clkrpc.c b/sys/fs/nfsclient/nfs_clkrpc.c
index 8b0b234..502fec5 100644
--- a/sys/fs/nfsclient/nfs_clkrpc.c
+++ b/sys/fs/nfsclient/nfs_clkrpc.c
@@ -278,17 +278,15 @@ nfsrvd_cbinit(int terminating)
 		while (nfs_numnfscbd > 0)
 			msleep(&nfs_numnfscbd, NFSDLOCKMUTEXPTR, PZERO, 
 			    "nfscbdt", 0);
-		NFSD_UNLOCK();
-		svcpool_destroy(nfscbd_pool);
-		nfscbd_pool = NULL;
-	} else
-		NFSD_UNLOCK();
-
-	nfscbd_pool = svcpool_create("nfscbd", NULL);
-	nfscbd_pool->sp_rcache = NULL;
-	nfscbd_pool->sp_assign = NULL;
-	nfscbd_pool->sp_done = NULL;
+	}
 
-	NFSD_LOCK();
+	if (nfscbd_pool == NULL) {
+		NFSD_UNLOCK();
+		nfscbd_pool = svcpool_create("nfscbd", NULL);
+		nfscbd_pool->sp_rcache = NULL;
+		nfscbd_pool->sp_assign = NULL;
+		nfscbd_pool->sp_done = NULL;
+		NFSD_LOCK();
+	}
 }