Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932844Ab3DZCJu (ORCPT ); Thu, 25 Apr 2013 22:09:50 -0400 Received: from mail-da0-f41.google.com ([209.85.210.41]:50527 "EHLO mail-da0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758781Ab3DZCJs (ORCPT ); Thu, 25 Apr 2013 22:09:48 -0400 Message-ID: <5179E1E1.4050304@chrisli.org> Date: Thu, 25 Apr 2013 19:09:37 -0700 From: Christopher Li User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130402 Thunderbird/17.0.5 MIME-Version: 1.0 To: Dan Carpenter CC: Andrew Morton , kbuild test robot , Jingoo Han , kbuild-all@01.org, Linux-Sparse , linux-kernel Subject: [PATCH] forced argument Was Re: sparse: incorrect type in argument 1 (different address spaces) References: <5171d93a.0NZAGYYKNj8hjsAs%fengguang.wu@intel.com> <20130422165629.bae79e6c5251bf148a3bae73@linux-foundation.org> <20130423061600.GN6638@mwanda> In-Reply-To: <20130423061600.GN6638@mwanda> Content-Type: multipart/mixed; boundary="------------050208040901030504040708" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3509 Lines: 123 This is a multi-part message in MIME format. --------------050208040901030504040708 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit On 04/22/2013 11:16 PM, Dan Carpenter wrote: > That didn't work. It's the the void * in the parameter list that's > the problem. We'd need to do something like the patch below: > > Otherwise we could add "__ok_to_cast" thing to Sparse maybe? Thanks for the insight. I make a small patch to test the __ok_to_cast feature. The syntax is adding the force attribute to the argument declaration. it will look like this: static inline long __must_check PTR_ERR( __force const void *ptr) That means the "ptr" argument will perform a forced cast when receiving the argument. It is OK to pass __iomem pointer to "ptr". The example are in the patch. It need to patch both sparse and the Linux tree. What do you say? Chris --------------050208040901030504040708 Content-Type: text/x-patch; name="0001-Allow-forced-attribute-in-function-argument.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename*0="0001-Allow-forced-attribute-in-function-argument.patch" >From a0974ed0fc1e67c41608c780b748c205622956b8 Mon Sep 17 00:00:00 2001 From: Christopher Li Date: Thu, 25 Apr 2013 18:09:43 -0700 Subject: [PATCH] Allow forced attribute in function argument It will indicate this argument will skip the compatible check. --- evaluate.c | 2 +- parse.c | 1 + symbol.h | 3 ++- validation/fored_arg.c | 18 ++++++++++++++++++ 4 files changed, 22 insertions(+), 2 deletions(-) create mode 100644 validation/fored_arg.c diff --git a/evaluate.c b/evaluate.c index 9f2c4ac..0dfa519 100644 --- a/evaluate.c +++ b/evaluate.c @@ -2137,7 +2137,7 @@ static int evaluate_arguments(struct symbol *f, struct symbol *fn, struct expres else degenerate(expr); } - } else { + } else if (!target->forced_arg){ static char where[30]; examine_symbol_type(target); sprintf(where, "argument %d", i); diff --git a/parse.c b/parse.c index 45ffc10..890e56b 100644 --- a/parse.c +++ b/parse.c @@ -1841,6 +1841,7 @@ static struct token *parameter_declaration(struct token *token, struct symbol *s sym->ctype = ctx.ctype; sym->ctype.modifiers |= storage_modifiers(&ctx); sym->endpos = token->pos; + sym->forced_arg = ctx.storage_class == SForced; return token; } diff --git a/symbol.h b/symbol.h index 1e74579..1c6ad66 100644 --- a/symbol.h +++ b/symbol.h @@ -157,7 +157,8 @@ struct symbol { expanding:1, evaluated:1, string:1, - designated_init:1; + designated_init:1, + forced_arg:1; struct expression *array_size; struct ctype ctype; struct symbol_list *arguments; diff --git a/validation/fored_arg.c b/validation/fored_arg.c new file mode 100644 index 0000000..4ab7141 --- /dev/null +++ b/validation/fored_arg.c @@ -0,0 +1,18 @@ +/* + * check-name: Forced function argument type. + */ + +#define __iomem __attribute__((noderef, address_space(2))) +#define __force __attribute__((force)) + +static void foo(__force void * addr) +{ +} + + +static void bar(void) +{ + void __iomem *a; + foo(a); +} + -- 1.8.1.4 --------------050208040901030504040708-- -- 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/