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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 ABDE2C433E6 for ; Mon, 4 Jan 2021 11:34:34 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1C813221F9 for ; Mon, 4 Jan 2021 11:34:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1C813221F9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 084E06B00A4; Mon, 4 Jan 2021 06:34:33 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 034D86B00A7; Mon, 4 Jan 2021 06:34:32 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E65F46B00A8; Mon, 4 Jan 2021 06:34:32 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0041.hostedemail.com [216.40.44.41]) by kanga.kvack.org (Postfix) with ESMTP id D038F6B00A4 for ; Mon, 4 Jan 2021 06:34:32 -0500 (EST) Received: from smtpin12.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 9950A8248047 for ; Mon, 4 Jan 2021 11:34:32 +0000 (UTC) X-FDA: 77667884784.12.stage47_0600569274d0 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin12.hostedemail.com (Postfix) with ESMTP id 76850180101F5 for ; Mon, 4 Jan 2021 11:34:32 +0000 (UTC) X-HE-Tag: stage47_0600569274d0 X-Filterd-Recvd-Size: 3029 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Mon, 4 Jan 2021 11:34:31 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 9BDC8ACAF; Mon, 4 Jan 2021 11:34:30 +0000 (UTC) To: Arnd Bergmann , Andrew Morton , Nathan Chancellor , Nick Desaulniers , "Kirill A. Shutemov" , Wei Yang Cc: Arnd Bergmann , Dmitry Safonov <0x7f454c46@gmail.com>, Brian Geffon , linux-mm@kvack.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com References: <20201230154104.522605-1-arnd@kernel.org> From: Vlastimil Babka Subject: Re: [PATCH] mm/mremap: fix BUILD_BUG_ON() error in get_extent Message-ID: Date: Mon, 4 Jan 2021 12:34:29 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.1 MIME-Version: 1.0 In-Reply-To: <20201230154104.522605-1-arnd@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: The subject should say BUILD_BUG() On 12/30/20 4:40 PM, Arnd Bergmann wrote: > From: Arnd Bergmann >=20 > clang cannt evaluate this function argument at compile time > when the function is not inlined, which leads to a link > time failure: >=20 > ld.lld: error: undefined symbol: __compiletime_assert_414 >>>> referenced by mremap.c >>>> mremap.o:(get_extent) in archive mm/built-in.a >=20 > Mark the function as __always_inline to avoid it. Not sure if it's the ideal fix, maybe just convert it to BUG() instead? Functions shouldn't really have BUILD_BUG depending on parameters and rel= y on inlining to make it work... > Fixes: 9ad9718bfa41 ("mm/mremap: calculate extent in one place") I think it's rather this one that introduces the BUILD_BUG() ? c49dd3401802 ("mm: speedup mremap on 1GB or larger regions") > Signed-off-by: Arnd Bergmann > --- > mm/mremap.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) >=20 > diff --git a/mm/mremap.c b/mm/mremap.c > index c5590afe7165..1cb464a07184 100644 > --- a/mm/mremap.c > +++ b/mm/mremap.c > @@ -336,8 +336,9 @@ enum pgt_entry { > * valid. Else returns a smaller extent bounded by the end of the sour= ce and > * destination pgt_entry. > */ > -static unsigned long get_extent(enum pgt_entry entry, unsigned long ol= d_addr, > - unsigned long old_end, unsigned long new_addr) > +static __always_inline unsigned long get_extent(enum pgt_entry entry, > + unsigned long old_addr, unsigned long old_end, > + unsigned long new_addr) > { > unsigned long next, extent, mask, size; > =20 >=20