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=-1.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, TVD_SUBJ_WIPE_DEBT autolearn=no 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 E4695C433DB for ; Thu, 11 Feb 2021 22:49:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2AC364E3E for ; Thu, 11 Feb 2021 22:49:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230116AbhBKWsp (ORCPT ); Thu, 11 Feb 2021 17:48:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34222 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229478AbhBKWsm (ORCPT ); Thu, 11 Feb 2021 17:48:42 -0500 Received: from mail-pf1-x430.google.com (mail-pf1-x430.google.com [IPv6:2607:f8b0:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C9ECC061574 for ; Thu, 11 Feb 2021 14:48:02 -0800 (PST) Received: by mail-pf1-x430.google.com with SMTP id b145so4648900pfb.4 for ; Thu, 11 Feb 2021 14:48:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:subject:to:cc:references:in-reply-to:mime-version :message-id:content-transfer-encoding; bh=WGBp0ms4trj4KJqYXx6s0gKRNvvrRpdSE+7mGZ4gKjo=; b=AsANI1TKW9wcXEIi4LEtOUxUNpQayajFoWP7YZ95m7XCh841Ai93sD6PPWxOs1HrCU KLifIGaiusRJ0RLzwKYHEWn7VejMLbo/L/UfSmjd8wD46Df0unMC3iqI/MyxpoW4tA7a 5gPgoIkiyPiYDV1VkPTE+PliqL6iNwUwXcX8UrswcQ09T+gpIyB6rqYoLNPnfTO2EVw7 H0xNJpzLjUU1UplPqkM3wz68SsvW4ICrfnA6OHJnQYUn2nvsmywbAN1+gGrDa3YeoSd1 bRnNdhxaZWgAEbdWgRE/Ag2lrv76CA99xEAVfwXibiYJRkH8GzPgxqR7vvd7TAF0JkZV 29IA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:subject:to:cc:references:in-reply-to :mime-version:message-id:content-transfer-encoding; bh=WGBp0ms4trj4KJqYXx6s0gKRNvvrRpdSE+7mGZ4gKjo=; b=SIhc/GsNMbhJu3IQNLwU9F0Em7Qbn68ZY/QyGXwosr4ejoMDncEeFPTjl+uacZmQHv VXVi5ZRUr3YAGUVjXTmHLc3TPNqeyVBLZkuKX9m7WkSDcidoRGWRZ7Z6P/6FuQW/nRPc X/nLZw/8W3Cr9PYyCFvtVB4zom4dHCp8Ok+0y1sf+HvGSeNUt5FLDuyHxoaVDH91oUpa drt+NsPe+o6rttVk6T24pRQpKHiR9iCQm91PdwLaNHehRI6OPuBk1F5Nvg+4BDYHL2Di Xd2a8vCyvFlH1eNJecU5KTj0YhIZUZlAgxXMHkl4C/jX955gm/jDdMG8p0yoH08pGnPP lrxQ== X-Gm-Message-State: AOAM533hE1AgqCMZmiQUJTSVjLn+kMZasjKvKR48zSD7iNQC1UEYxaBM IrzzXcaP92rXr64cImD5unzPbg6Vzkk= X-Google-Smtp-Source: ABdhPJwvz8NkBzT3VZIsgga9RgZijGc00zoDlZLVlsIEeO9JeUJdtdmHJB4GLs8GlIbfIgvcvJeHKg== X-Received: by 2002:a62:18c8:0:b029:1d9:6e93:6b22 with SMTP id 191-20020a6218c80000b02901d96e936b22mr339226pfy.28.1613083682147; Thu, 11 Feb 2021 14:48:02 -0800 (PST) Received: from localhost (14-201-150-91.tpgi.com.au. [14.201.150.91]) by smtp.gmail.com with ESMTPSA id j9sm6369183pfh.52.2021.02.11.14.48.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 14:48:01 -0800 (PST) Date: Fri, 12 Feb 2021 08:47:55 +1000 From: Nicholas Piggin Subject: Re: [PATCH] powerpc/bug: Remove specific powerpc BUG_ON() To: Segher Boessenkool Cc: Benjamin Herrenschmidt , Christophe Leroy , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Michael Ellerman , Paul Mackerras References: <694c7195c81d1bcc781b3c14f452886683d6c524.1613029237.git.christophe.leroy@csgroup.eu> <1613036567.zvyupcz926.astroid@bobo.none> <20210211115059.GB28121@gate.crashing.org> In-Reply-To: <20210211115059.GB28121@gate.crashing.org> MIME-Version: 1.0 Message-Id: <1613083544.ggx0xcefkc.astroid@bobo.none> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Excerpts from Segher Boessenkool's message of February 11, 2021 9:50 pm: > On Thu, Feb 11, 2021 at 08:04:55PM +1000, Nicholas Piggin wrote: >> It would be nice if we could have a __builtin_trap_if that gcc would use= =20 >> conditional traps with, (and which never assumes following code is=20 >> unreachable even for constant true, so we can use it with WARN and put=20 >> explicit unreachable for BUG). >=20 > It automatically does that with just __builtin_trap, see my other mail :-= ) If that is generated without branches (or at least with no more branches than existing asm implementation), then it could be usable=20 without trashing CFAR. Unfortunately I don't think we will be parsing the dwarf information to get line numbers from it any time soon, so not a drop in replacement=20 but maybe one day someone would find a solution. Thanks, Nick