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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C2584C433EF for ; Thu, 12 May 2022 14:07:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1DD4F6B0074; Thu, 12 May 2022 10:07:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 18BEF6B0075; Thu, 12 May 2022 10:07:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0542A6B0078; Thu, 12 May 2022 10:07:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id EBB196B0074 for ; Thu, 12 May 2022 10:07:39 -0400 (EDT) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id BCB6D604FB for ; Thu, 12 May 2022 14:07:39 +0000 (UTC) X-FDA: 79457269038.20.5762D49 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf24.hostedemail.com (Postfix) with ESMTP id AF3AF1800E1 for ; Thu, 12 May 2022 14:07:29 +0000 (UTC) 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=9py6ogGa9oM8eFz+r/oJ/gtHX4WV1rBXNn56XWgDhJo=; b=g3/9RZGpqQT7hqtylUfNmBua4h npUP84ab6kqiLc+k1Ydo7u75/73h9GflPgoI3VkeczSc0mDGWDqpRl+PhLvM8kg/TKY8p+Dmg9+UJ CHMFo0A18xag9YhjdRI6CR7an5D6mc5yAkL4LaIFsHdkAjX/KXgOlL4O5nJZOQpsiHXOoLi2d04dy YvWLOUtY5gzzf4d4LK/PGwVBPFi7KVttAo0JTdGlZKzP0vymaIrUs+RNjqVfM0vby3RYXipjNAA0I iBh0rFa7Ks9ZHEliknjtMg1WP+MFijg4jmaODnJfWz8JlVo3OzwKjEoYJZ9FEQSe11EF67rHeOLfi rLk2+u5g==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1np9TN-006SMQ-Hk; Thu, 12 May 2022 14:07:21 +0000 Date: Thu, 12 May 2022 15:07:21 +0100 From: Matthew Wilcox To: David Laight Cc: "'Kirill A. Shutemov'" , Dave Hansen , Andy Lutomirski , Peter Zijlstra , "x86@kernel.org" , Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , "H . J . Lu" , Andi Kleen , Rick Edgecombe , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] x86: Implement Linear Address Masking support Message-ID: References: <20220511022751.65540-1-kirill.shutemov@linux.intel.com> <20220511022751.65540-2-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: AF3AF1800E1 X-Stat-Signature: 3o3acqta3ui771t9kwtqdzocpgxjkp4o Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b="g3/9RZGp"; dmarc=none; spf=none (imf24.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org X-Rspam-User: X-HE-Tag: 1652364449-889910 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: On Thu, May 12, 2022 at 01:01:07PM +0000, David Laight wrote: > > +static inline int64_t sign_extend64(uint64_t value, int index) > > +{ > > + int shift = 63 - index; > > + return (int64_t)(value << shift) >> shift; > > +} > > Shift of signed integers are UB. Citation needed.