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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 9FAA7C433E0 for ; Wed, 30 Dec 2020 14:18:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6ED81221F8 for ; Wed, 30 Dec 2020 14:18:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726276AbgL3OSh (ORCPT ); Wed, 30 Dec 2020 09:18:37 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:35877 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725814AbgL3OSg (ORCPT ); Wed, 30 Dec 2020 09:18:36 -0500 Received: from ip5f5af0a0.dynamic.kabel-deutschland.de ([95.90.240.160] helo=wittgenstein) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1kucIV-0001NV-5u; Wed, 30 Dec 2020 14:17:55 +0000 Date: Wed, 30 Dec 2020 15:17:53 +0100 From: Christian Brauner To: Jens Axboe Cc: io-uring Subject: Re: [PATCH] io_uring: don't assume mm is constant across submits Message-ID: <20201230141753.hakwbf6c6xw2ohts@wittgenstein> References: <7224e4df-50e9-ffd1-5453-391802fcded7@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <7224e4df-50e9-ffd1-5453-391802fcded7@kernel.dk> Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Tue, Dec 29, 2020 at 10:53:21AM -0700, Jens Axboe wrote: > If we COW the identity, we assume that ->mm never changes. But this > isn't true of multiple processes end up sharing the ring. Hence treat > id->mm like like any other process compontent when it comes to the > identity mapping. > > Reported-by: Christian Brauner : > Tested-by: Christian Brauner : > Signed-off-by: Jens Axboe > > --- Thanks for fixing this! Fwiw, tested again just now. Reviewed-by: Christian Brauner