From: Jia-Ju Bai <baijiaju1990@gmail.com>
To: jon.maloy@ericsson.com, ying.xue@windriver.com, davem@davemloft.net
Cc: netdev@vger.kernel.org, tipc-discussion@lists.sourceforge.net,
linux-kernel@vger.kernel.org, Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [PATCH v2] net: tipc: Replace GFP_ATOMIC with GFP_KERNEL in tipc_mon_create
Date: Tue, 10 Apr 2018 09:17:33 +0800 [thread overview]
Message-ID: <1523323053-28127-1-git-send-email-baijiaju1990@gmail.com> (raw)
tipc_mon_create() is never called in atomic context.
The call chain ending up at dn_route_init() is:
[1] tipc_mon_create() <- tipc_enable_bearer() <- tipc_nl_bearer_enable()
tipc_nl_bearer_enable() calls rtnl_lock(), which indicates this function
is not called in atomic context.
Despite never getting called from atomic context,
tipc_mon_create() calls kzalloc() 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 <baijiaju1990@gmail.com>
---
v2:
* Modify the description of GFP_ATOMIC in v1.
Thank Eric for good advice.
---
net/tipc/monitor.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/net/tipc/monitor.c b/net/tipc/monitor.c
index 9e109bb..9714d80 100644
--- a/net/tipc/monitor.c
+++ b/net/tipc/monitor.c
@@ -604,9 +604,9 @@ int tipc_mon_create(struct net *net, int bearer_id)
if (tn->monitors[bearer_id])
return 0;
- mon = kzalloc(sizeof(*mon), GFP_ATOMIC);
- self = kzalloc(sizeof(*self), GFP_ATOMIC);
- dom = kzalloc(sizeof(*dom), GFP_ATOMIC);
+ mon = kzalloc(sizeof(*mon), GFP_KERNEL);
+ self = kzalloc(sizeof(*self), GFP_KERNEL);
+ dom = kzalloc(sizeof(*dom), GFP_KERNEL);
if (!mon || !self || !dom) {
kfree(mon);
kfree(self);
--
1.9.1
next reply other threads:[~2018-04-10 1:17 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-10 1:17 Jia-Ju Bai [this message]
2018-04-11 10:11 ` [PATCH v2] net: tipc: Replace GFP_ATOMIC with GFP_KERNEL in tipc_mon_create Ying Xue
2018-04-11 10:18 ` Jia-Ju Bai
-- strict thread matches above, loose matches on Subject: below --
2018-04-10 1:16 Jia-Ju Bai
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