From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.135]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3s3SwR59WzzDrKJ for ; Tue, 2 Aug 2016 17:47:34 +1000 (AEST) From: Arnd Bergmann To: linuxppc-dev@lists.ozlabs.org Cc: Scott Wood , "qiang.zhao@freescale.com" , "viresh.kumar@linaro.org" , "zajec5@gmail.com" , "linux-wireless@vger.kernel.org" , "David.Laight@aculab.com" , "netdev@vger.kernel.org" , "scottwood@freescale.com" , Arvind Yadav , "akpm@linux-foundation.org" , "davem@davemloft.net" , "linux@roeck-us.net" Subject: Re: [v4] Fix to avoid IS_ERR_VALUE and IS_ERR abuses on 64bit systems. Date: Tue, 02 Aug 2016 09:45:18 +0200 Message-ID: <2484583.95xFmO7xir@wuerfel> In-Reply-To: References: <1469963924-8800-1-git-send-email-arvind.yadav.cs@gmail.com> <1956647.cOmaJREgOE@wuerfel> 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: , On Monday, August 1, 2016 4:55:43 PM CEST Scott Wood wrote: > On 08/01/2016 02:02 AM, Arnd Bergmann wrote: > >> diff --git a/include/linux/err.h b/include/linux/err.h > >> index 1e35588..c2a2789 100644 > >> --- a/include/linux/err.h > >> +++ b/include/linux/err.h > >> @@ -18,7 +18,17 @@ > >> > >> #ifndef __ASSEMBLY__ > >> > >> -#define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO) > >> +#define IS_ERR_VALUE(x) unlikely(is_error_check(x)) > >> + > >> +static inline int is_error_check(unsigned long error) > > > > Please leave the existing macro alone. I think you were looking for > > something specific to the return code of qe_muram_alloc() function, > > so please add a helper in that subsystem if you need it, not in > > the generic header files. > > qe_muram_alloc (a.k.a. cpm_muram_alloc) returns unsigned long. The > problem is certain callers that store the return value in a u32. Why > not just fix those callers to store it in unsigned long (at least until > error checking is done)? > Yes, that would also address another problem with code like kfree((void *)ugeth->tx_bd_ring_offset[i]); which is not 64-bit safe when tx_bd_ring_offset is a 32-bit value that also holds the return value of qe_muram_alloc. Arnd