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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 572C4C433FE for ; Wed, 10 Nov 2021 10:46:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B6A861168 for ; Wed, 10 Nov 2021 10:46:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231250AbhKJKte convert rfc822-to-8bit (ORCPT ); Wed, 10 Nov 2021 05:49:34 -0500 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]:49628 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231175AbhKJKtd (ORCPT ); Wed, 10 Nov 2021 05:49:33 -0500 Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-287-8KJ161tcNHKlvygMg9XwRA-1; Wed, 10 Nov 2021 10:46:44 +0000 X-MC-Unique: 8KJ161tcNHKlvygMg9XwRA-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) by AcuMS.aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) with Microsoft SMTP Server (TLS) id 15.0.1497.24; Wed, 10 Nov 2021 10:46:42 +0000 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.024; Wed, 10 Nov 2021 10:46:42 +0000 From: David Laight To: 'Peter Zijlstra' , Nick Desaulniers CC: Bill Wendling , Josh Poimboeuf , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "mark.rutland@arm.com" , "dvyukov@google.com" , "seanjc@google.com" , "pbonzini@redhat.com" , "mbenes@suse.cz" , "llvm@lists.linux.dev" , "linux-toolchains@vger.kernel.org" Subject: RE: [PATCH 20/22] x86,word-at-a-time: Remove .fixup usage Thread-Topic: [PATCH 20/22] x86,word-at-a-time: Remove .fixup usage Thread-Index: AQHX1a3cTPOCK2YRr06RWvi0T9RbLav8lJ+g Date: Wed, 10 Nov 2021 10:46:42 +0000 Message-ID: References: <20211105171023.989862879@infradead.org> <20211105171821.654356149@infradead.org> <20211108164711.mr2cqdcvedin2lvx@treble> <20211109210736.GV174703@worktop.programming.kicks-ass.net> In-Reply-To: <20211109210736.GV174703@worktop.programming.kicks-ass.net> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Peter Zijlstra > Sent: 09 November 2021 21:08 ... > > GCC does the same, but I wanted to have the exception stuff be in > .text.cold, but alas it doesn't do that. I left the attribute because of > it's descriptive value. > > > Unless the cold attribute is helping move > > ("shrink-wrap"?) the basic block to a whole other section > > (.text.cold.)? > > I was hoping it would do that, but it doesn't on gcc-11. Wouldn't moving part of a function to .text.cold (or .text.unlikely) generate the same problems with the stack backtrace code as the .text.fixup section you are removing had?? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)