SUNRPC: Dont run rpcauth_cache_shrinker() when gfp_mask is GFP_NOFS

Under some circumstances, put_rpccred() can end up allocating memory, so
check the gfp_mask to prevent deadlocks.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 95afe79..0667a36 100644 (file)
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -270,6 +270,8 @@ rpcauth_cache_shrinker(int nr_to_scan, gfp_t gfp_mask)
        LIST_HEAD(free);
        int res;
 
        LIST_HEAD(free);
        int res;
 

+       if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
+               return (nr_to_scan == 0) ? 0 : -1;

        if (list_empty(&cred_unused))
                return 0;
        spin_lock(&rpc_credcache_lock);
        if (list_empty(&cred_unused))
                return 0;
        spin_lock(&rpc_credcache_lock);