From: Trond Myklebust <Trond.Myklebust@netapp.com>
Date: Thu, 13 May 2010 16:51:03 +0000 (-0400)
Subject: SUNRPC: Dont run rpcauth_cache_shrinker() when gfp_mask is GFP_NOFS
X-Git-Tag: v2.6.35-rc1~490^2~9
X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=commitdiff_plain;h=d300a41ef1c39cc5e6b90fd8834ea7ab16b5c48f

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
--- 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;
 
+	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);