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=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,TRACKER_ID 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 CC20DC433ED for ; Fri, 16 Apr 2021 18:11:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A58816137D for ; Fri, 16 Apr 2021 18:11:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244400AbhDPSLg (ORCPT ); Fri, 16 Apr 2021 14:11:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244362AbhDPSLf (ORCPT ); Fri, 16 Apr 2021 14:11:35 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C87E2C061574; Fri, 16 Apr 2021 11:11:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=iy+YquCQolFdhIFqaFYddxkruv3V6Zn88c7KpgInMyI=; b=oZ3MAr1HcgC8j/7GZ0Rqd8avEW oDQP525+WZ6SRSMzTL/fDoBmU2oyLhIPa6ZDdXj+E98Rfch1fmDBiEhxfqO0IgQTsOZCLtlXC4eGu Q9gbp7N2t4fyhg7zai6c0Wwhh5BA0yt+KznYssYMlVKFfW9Gu3cydiA94cU5G7o4IE2ZDbFxj71bS /DX+Vhnvo0arE6cdvR36QjL/A41Fn36WoIbviaI7C7Ft0yUUfad7wEs/9hCyuR7gM6N83bC5U8zcZ NyO2gnTg1HAE4A0PfneTSPaJXjidrc2ULpKLxgr0/3gaQjiR9oJ9rHwz5W0hLV/r8snMu50G4Zu4b hcanTdBw==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lXStJ-00AHbV-FC; Fri, 16 Apr 2021 18:09:04 +0000 Date: Fri, 16 Apr 2021 19:08:29 +0100 From: Matthew Wilcox To: Peter Zijlstra Cc: Miguel Ojeda , Willy Tarreau , Wedson Almeida Filho , Miguel Ojeda , Linus Torvalds , Greg Kroah-Hartman , rust-for-linux@vger.kernel.org, Linux Kbuild mailing list , Linux Doc Mailing List , linux-kernel Subject: Re: [PATCH 00/13] [RFC] Rust support Message-ID: <20210416180829.GO2531743@casper.infradead.org> References: <20210414184604.23473-1-ojeda@kernel.org> <20210416161444.GA10484@1wt.eu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: rust-for-linux@vger.kernel.org On Fri, Apr 16, 2021 at 07:18:48PM +0200, Peter Zijlstra wrote: > On Fri, Apr 16, 2021 at 07:10:17PM +0200, Miguel Ojeda wrote: > > > Of course, UB is only a subset of errors, but it is a major one, and > > particularly critical for privileged code. > > I've seen relatively few UBSAN warnings that weren't due to UBSAN being > broken. Lucky you. 84c34df158cf215b0cd1475ab3b8e6f212f81f23 (i'd argue this is C being broken; promoting only as far as int, when assigning to an unsigned long is Bad, but until/unless either GCC fixes that or the language committee realises that being stuck in the 1970s is Bad, people are going to keep making this kind of mistake)