From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id F004AB7067 for ; Mon, 13 Jul 2009 06:43:27 +1000 (EST) Received: from mgw1.diku.dk (mgw1.diku.dk [130.225.96.91]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mgw1.diku.dk", Issuer "KU Security Authority" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 82A34DDDE7 for ; Mon, 13 Jul 2009 06:43:27 +1000 (EST) Date: Sun, 12 Jul 2009 22:03:42 +0200 (CEST) From: Julia Lawall To: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH 1/5] drivers/char/hvc_console.c: Drop unnecessary NULL test Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Julia Lawall 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/) // @@ 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 ... } // Signed-off-by: Julia Lawall --- drivers/char/hvc_console.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c index 94e7e3c..e367630 100644 --- a/drivers/char/hvc_console.c +++ b/drivers/char/hvc_console.c @@ -516,8 +516,6 @@ static void hvc_set_winsz(struct work_struct *work) struct winsize ws; hp = container_of(work, struct hvc_struct, tty_resize); - if (!hp) - return; spin_lock_irqsave(&hp->lock, hvc_flags); if (!hp->tty) {