[PATCH 5/5] net/irda: Drop unnecessary NULL test

From: Julia Lawall
Date: Sun Jul 12 2009 - 16:15:07 EST


From: Julia Lawall <julia@xxxxxxx>

The result of container_of should not be NULL. In particular, in this case
the argument to the enclosing function has passed though INIT_WORK, which
dereferences it, implying that its container cannot be NULL.

A simplified version of the semantic patch that makes this change is as
follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
identifier fn,work,x,fld;
type T;
expression E1,E2;
statement S;
@@

static fn(struct work_struct *work) {
... when != work = E1
x = container_of(work,T,fld)
... when != x = E2
- if (x == NULL) S
...
}
// </smpl>

Signed-off-by: Julia Lawall <julia@xxxxxxx>

---
net/irda/irnet/irnet_irda.c | 2 --
1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/net/irda/irnet/irnet_irda.c b/net/irda/irnet/irnet_irda.c
index cf9a4b5..49ed80d 100644
--- a/net/irda/irnet/irnet_irda.c
+++ b/net/irda/irnet/irnet_irda.c
@@ -21,8 +21,6 @@ static void irnet_ppp_disconnect(struct work_struct *work)
irnet_socket * self =
container_of(work, irnet_socket, disconnect_work);

- if (self == NULL)
- return;
/*
* If we were connected, cleanup & close the PPP
* channel, which will kill pppd (hangup) and the rest.
--
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