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[209.132.180.67]) by mx.google.com with ESMTP id w1si21016590oia.169.2020.01.22.00.50.11; Wed, 22 Jan 2020 00:50:23 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@infradead.org header.s=bombadil.20170209 header.b=PBZryFkN; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728916AbgAVItS (ORCPT + 99 others); Wed, 22 Jan 2020 03:49:18 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:47042 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725883AbgAVItS (ORCPT ); Wed, 22 Jan 2020 03:49:18 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=YCaO7HkGDxrq9uLeSsmssHBPXstORVfrji7Ya82A6ow=; b=PBZryFkN7FC0BHIdjcadjnluY 3F/Z7Lu1TSTlHaw3CydYtJIXZVTAJyy7f3/Apj2YOlxDOozUOnmwwekxLBYgirt9ETkOhAA7qKfgA X3UGUF3In4IqthKVlMA509WVRTdL0+VSMSj7+CP6XBjIk87bMjt1i3qyJnndgFB0DaOMzoB8UdItI 9SWKyYlnUSQbPcnnfzgGXmEShdDfGoKuXJHKbqQLXuhTtjE1g7hiV0KJYkb+rcal9IhELt3OvAhfO 6B3EO1ZF2+QKlFM1VExdc+vtGUFpzzjPHRpTYj9tvPKPJZww6EBw4jqA7v4zQBPxXyzkFDBFR+3xf tmIJFVoVQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iuBhB-0000IC-2I; Wed, 22 Jan 2020 08:49:05 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id D7315304121; Wed, 22 Jan 2020 09:47:22 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 262E82B703E5E; Wed, 22 Jan 2020 09:49:02 +0100 (CET) Date: Wed, 22 Jan 2020 09:49:02 +0100 From: Peter Zijlstra To: Eric Dumazet Cc: Shaokun Zhang , Eric Dumazet , David Miller , netdev , LKML , jinyuqi@huawei.com, Alexey Kuznetsov , Hideaki YOSHIFUJI , guoyang2@huawei.com, Will Deacon Subject: Re: [PATCH] net: optimize cmpxchg in ip_idents_reserve Message-ID: <20200122084902.GQ14914@hirez.programming.kicks-ass.net> References: <1579058620-26684-1-git-send-email-zhangshaokun@hisilicon.com> <20200116.042722.153124126288244814.davem@davemloft.net> <930faaff-4d18-452d-2e44-ef05b65dc858@gmail.com> <1b3aaddf-22f5-1846-90f1-42e68583c1e4@gmail.com> <430496fc-9f26-8cb4-91d8-505fda9af230@hisilicon.com> <20200117123253.GC14879@hirez.programming.kicks-ass.net> <5fd55696-e46c-4269-c106-79782efb0dd8@hisilicon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jan 18, 2020 at 08:12:48PM -0800, Eric Dumazet wrote: > Instead the changelog should be explaining why the revert is now safe. FWIW, it was always safe, UBSAN was just buggy.