From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D4EEDC47247 for ; Tue, 5 May 2020 14:12:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B11A62078C for ; Tue, 5 May 2020 14:12:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="gSAzcE/c" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729086AbgEEOMq (ORCPT ); Tue, 5 May 2020 10:12:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728135AbgEEOMp (ORCPT ); Tue, 5 May 2020 10:12:45 -0400 Received: from mail-oi1-x243.google.com (mail-oi1-x243.google.com [IPv6:2607:f8b0:4864:20::243]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5ACFFC061A0F for ; Tue, 5 May 2020 07:12:45 -0700 (PDT) Received: by mail-oi1-x243.google.com with SMTP id m10so2041969oie.6 for ; Tue, 05 May 2020 07:12:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Yjm2cmKVuwlkstPxfFd5MfjFWk/J8R1nDWAUw4Id7r8=; b=gSAzcE/ceHx3DD0GHkL/zUqm0ntyLCzjEfid4HO8kPLsHnWLW/F0L8YI2ve23ScdUX SR0Z5J4h4hYUhRAu0sf2GUNqwtltdFruppAAsoH8zwvvowS4uwWSYI6fT1Q8LSRLegaC J6UdM/icnIHrSTh/q0fEzggv34Jrmx9+Lr8NMLddFudUi4U5QiM/RI/uAJB0oFvMPzbz izKi+kCspKWbqnxBLxwB8Elc4lL3Z7ABEXerd1WoTedVc/o4SczYSK0prr4dF5Pix0w4 ogM72D79j8OK39H5K1HkLXMQe39tDXPeZsYE5K/oiYsHvpadvrMniPLWrvwerrWTx8oq 1Nuw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Yjm2cmKVuwlkstPxfFd5MfjFWk/J8R1nDWAUw4Id7r8=; b=J1voC8KN/Zk6mXjXum7P16xhi0gzJIeKxBFWcy7SULj+A9L1MM2WZCB6XG7jn5MI4X ddL4PsvynFTBNTgBMBLmlNYP5tnmqt6pK0GsStplBrQDQff+vIPmo83myKbM8G3g9yzi nJ/CHVn+Fjig2bfWOZmLE8vaYRYzxOxv5ST6RSNcBlxH+PCEGhvkcP5eIrwlJcZ6iFxk VOBFxnQHqX2eWRxef09LINSqkiQuhoUKkBvGl5nspZm9glBcApM3ApV/IkEiEmKLwU4T Vur7kJKB+55nW7CzcPkirffqETiiM+bvW4mCXkv4TBeTN9q9Ve4DAUm/SpvcUdVSPflI Pe5g== X-Gm-Message-State: AGi0PuZkCdJGaJsiqA9++8E9qbLH16TI17sLhPg+kvPj7FSmxu8k+9rT +qIORsr8kGj0RXRjCtBMJ21BvP4rRxZrfm2tSTIc1w== X-Google-Smtp-Source: APiQypIAywvPjEF+eFOU7gfeqV9lG2oqecVKyu+ef21qclXSvVG9C5gqW2wVY/N0EBRjBC6fH8Vm74uN5E+0Jr0Owmg= X-Received: by 2002:aca:1c08:: with SMTP id c8mr2558360oic.172.1588687963483; Tue, 05 May 2020 07:12:43 -0700 (PDT) MIME-Version: 1.0 References: <20200505140407.373983-1-arnd@arndb.de> In-Reply-To: <20200505140407.373983-1-arnd@arndb.de> From: Marco Elver Date: Tue, 5 May 2020 16:12:30 +0200 Message-ID: Subject: Re: [PATCH] omapfb: don't annotate dss_conv_list as __initdata To: Arnd Bergmann Cc: Bartlomiej Zolnierkiewicz , "Paul E. McKenney" , Allison Randal , Alexios Zavras , Greg Kroah-Hartman , Enrico Weigelt , Thomas Gleixner , linux-omap@vger.kernel.org, linux-fbdev@vger.kernel.org, dri-devel , LKML , clang-built-linux@googlegroups.com, Will Deacon Content-Type: text/plain; charset="UTF-8" Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org On Tue, 5 May 2020 at 16:04, Arnd Bergmann wrote: > > With the kcsan changes, __read_once_size() is not inlined, but > clang can decide to emit a version that hardcodes the address, which > in turn triggers a warning for dss_conv_list being __initdata but > __read_once_size() not being __init: > > WARNING: modpost: vmlinux.o(.text+0x6e4d7a): Section mismatch in > reference from the function __read_once_size() to the variable > .init.data:dss_conv_list > The function __read_once_size() references > the variable __initdata dss_conv_list. > This is often because __read_once_size lacks a __initdata > annotation or the annotation of dss_conv_list is wrong. > > This is clearly a false positive warning, but it's hard to tell > who is to blame for it. Work around it by removing the __initdata > annotation, wasting the space of two pointers in return for getting > rid of the warning. > > Fixes: dfd402a4c4ba ("kcsan: Add Kernel Concurrency Sanitizer infrastructure") > Signed-off-by: Arnd Bergmann [+Cc Will] I think Will is working on a series that completely overhauls READ_ONCE/WRITE_ONCE, also getting rid of __read_once_size() in the process, which would make this patch redundant. If we can live with this warning until the new READ_ONCE/WRITE_ONCE gets merged, we can probably keep things as-is for now. Thanks, -- Marco > --- > drivers/video/fbdev/omap2/omapfb/dss/omapdss-boot-init.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/video/fbdev/omap2/omapfb/dss/omapdss-boot-init.c b/drivers/video/fbdev/omap2/omapfb/dss/omapdss-boot-init.c > index 0ae0cab252d3..29fdff9c95f6 100644 > --- a/drivers/video/fbdev/omap2/omapfb/dss/omapdss-boot-init.c > +++ b/drivers/video/fbdev/omap2/omapfb/dss/omapdss-boot-init.c > @@ -19,7 +19,7 @@ > #include > #include > > -static struct list_head dss_conv_list __initdata; > +static struct list_head dss_conv_list; > > static const char prefix[] __initconst = "omapdss,"; > > -- > 2.26.0 >