Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753011AbaA3LuH (ORCPT ); Thu, 30 Jan 2014 06:50:07 -0500 Received: from aserp1040.oracle.com ([141.146.126.69]:34902 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752657AbaA3LuF (ORCPT ); Thu, 30 Jan 2014 06:50:05 -0500 Date: Thu, 30 Jan 2014 14:49:43 +0300 From: Dan Carpenter To: Matt Mackall Cc: Herbert Xu , Rusty Russell , Satoru Takeuchi , Paul Gortmaker , linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [patch] hw_random: cleanup in hwrng_register() Message-ID: <20140130114943.GB12734@elgon.mountain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org My static checker complains that: drivers/char/hw_random/core.c:341 hwrng_register() warn: we tested 'old_rng' before and it was 'false' The problem is that sometimes we test "if (!old_rng)" and sometimes we test "if (must_register_misc)". The static checker knows they are equivalent but a human being reading the code could easily be confused. I have simplified the code by removing the "must_register_misc" variable and I have removed the redundant check on "if (!old_rng)". Signed-off-by: Dan Carpenter diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index b9495a8c05c6..463382036a01 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -301,7 +301,6 @@ err_misc_dereg: int hwrng_register(struct hwrng *rng) { - int must_register_misc; int err = -EINVAL; struct hwrng *old_rng, *tmp; @@ -326,7 +325,6 @@ int hwrng_register(struct hwrng *rng) goto out_unlock; } - must_register_misc = (current_rng == NULL); old_rng = current_rng; if (!old_rng) { err = hwrng_init(rng); @@ -335,13 +333,11 @@ int hwrng_register(struct hwrng *rng) current_rng = rng; } err = 0; - if (must_register_misc) { + if (!old_rng) { err = register_miscdev(); if (err) { - if (!old_rng) { - hwrng_cleanup(rng); - current_rng = NULL; - } + hwrng_cleanup(rng); + current_rng = NULL; goto out_unlock; } } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/