From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jia-Ju Bai Subject: [PATCH v2] net: dccp: Replace GFP_ATOMIC with GFP_KERNEL in dccp_init Date: Tue, 10 Apr 2018 09:14:58 +0800 Message-ID: <1523322898-27833-1-git-send-email-baijiaju1990@gmail.com> Cc: dccp@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai To: gerrit@erg.abdn.ac.uk, davem@davemloft.net Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org dccp_init() is never called in atomic context. This function is only set as a parameter of module_init(). Despite never getting called from atomic context, dccp_init() calls __get_free_pages() with GFP_ATOMIC, which does not sleep for allocation. GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL, which can sleep and improve the possibility of sucessful allocation. This is found by a static analysis tool named DCNS written by myself. And I also manually check it. Signed-off-by: Jia-Ju Bai --- v2: * Modify the description of GFP_ATOMIC in v1. Thank Eric for good advice. --- net/dccp/proto.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/dccp/proto.c b/net/dccp/proto.c index b68168f..f63ba93 100644 --- a/net/dccp/proto.c +++ b/net/dccp/proto.c @@ -1159,7 +1159,7 @@ static int __init dccp_init(void) hash_size--; dccp_hashinfo.ehash_mask = hash_size - 1; dccp_hashinfo.ehash = (struct inet_ehash_bucket *) - __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order); + __get_free_pages(GFP_KERNEL|__GFP_NOWARN, ehash_order); } while (!dccp_hashinfo.ehash && --ehash_order > 0); if (!dccp_hashinfo.ehash) { @@ -1182,7 +1182,7 @@ static int __init dccp_init(void) bhash_order > 0) continue; dccp_hashinfo.bhash = (struct inet_bind_hashbucket *) - __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, bhash_order); + __get_free_pages(GFP_KERNEL|__GFP_NOWARN, bhash_order); } while (!dccp_hashinfo.bhash && --bhash_order >= 0); if (!dccp_hashinfo.bhash) { -- 1.9.1