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=-4.1 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 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 42D70C433E6 for ; Tue, 21 Jul 2020 19:56:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1CC112072E for ; Tue, 21 Jul 2020 19:56:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=anarazel.de header.i=@anarazel.de header.b="fimQshPg"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="K/5IJJUr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731020AbgGUT4H (ORCPT ); Tue, 21 Jul 2020 15:56:07 -0400 Received: from wnew3-smtp.messagingengine.com ([64.147.123.17]:44937 "EHLO wnew3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730664AbgGUT4H (ORCPT ); Tue, 21 Jul 2020 15:56:07 -0400 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailnew.west.internal (Postfix) with ESMTP id 1D38EB24; Tue, 21 Jul 2020 15:56:05 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Tue, 21 Jul 2020 15:56:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=anarazel.de; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm2; bh=AqPj1xBhDhu20FWDwJyJBEuqNaN WXORj4eQ/tBPqOlo=; b=fimQshPgm3sthCqApa+djmcfCkLSFwHY7QblvbjAlcv fPAeBpiKsqs0mi3QLh/mXmVgdoJGl9yF7GQdobNdc899gi75MM7QXJSWdeGAzP7s pSqG/bclBObeMUkxz/dRBESdzacl39lEoopnuJpHNa6X9FXj5KSV36Yywu6LzFHw 3zpOiEbxa7VY7ly3+0eWQJu/UGasSNqBBg0G6xEinO3fsdd0gj2taDBAEmvjobeS K5vsV8vy83764Ae5qR8ReCf/r3JLq6FCORMmJgZ/60QZzT4RIZEmQ0fN3oZb/CbS N9buoYDtMl3zFfWbIKyZrEurHDEhE/bkHpvmbn4Yutg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm3; bh=AqPj1x BhDhu20FWDwJyJBEuqNaNWXORj4eQ/tBPqOlo=; b=K/5IJJUrbwW7dfc8maPE+b At1jqzRMcstf7E7PyDytihqi9rgeeXyx3p0UJTKG3eIJTnB02AAm+JC3CkttZ1Nd N5rkxvIOVIKX0sXbOw6Xl0dJ6Si2ntASsU/3OSsxiTrWjuz7m829nn7ktLAS9vJj 1vx11jy/npcDV7Jc2zUTA74XOI1Kmtnw2OEoJCMvdXazgipT2WxsWbJ/ij9/DyHu FIVXQ2b1z72wtETwOJ6brF9P0Z/Q6A/Gve6m0KxtOEyKNilXxL0FjJn1JKD6gl/m d08EhKLjB0eiZWiicGMDLi507bD9Gf4F9WbkBlx52akc8iLr8JJURQhViOaQIvjQ == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduiedrgeejgddukecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpeffhffvuffkfhggtggujgesthdtredttddtvdenucfhrhhomheptehnughrvghs ucfhrhgvuhhnugcuoegrnhgurhgvshesrghnrghrrgiivghlrdguvgeqnecuggftrfgrth htvghrnhepudekhfekleeugeevteehleffffejgeelueduleeffeeutdelffeujeffhfeu ffdunecukfhppeeijedrudeitddrvddujedrvdehtdenucevlhhushhtvghrufhiiigvpe dtnecurfgrrhgrmhepmhgrihhlfhhrohhmpegrnhgurhgvshesrghnrghrrgiivghlrdgu vg X-ME-Proxy: Received: from intern.anarazel.de (c-67-160-217-250.hsd1.ca.comcast.net [67.160.217.250]) by mail.messagingengine.com (Postfix) with ESMTPA id 655F930600B1; Tue, 21 Jul 2020 15:56:03 -0400 (EDT) Date: Tue, 21 Jul 2020 12:56:02 -0700 From: Andres Freund To: Andy Lutomirski Cc: Jens Axboe , Stefano Garzarella , Christoph Hellwig , Kees Cook , Pavel Begunkov , Miklos Szeredi , Matthew Wilcox , Jann Horn , Christian Brauner , strace-devel@lists.strace.io, io-uring@vger.kernel.org, Linux API , Linux FS Devel , LKML , Michael Kerrisk , Stefan Hajnoczi Subject: Re: strace of io_uring events? Message-ID: <20200721195602.qtncgzddl7y55b6l@alap3.anarazel.de> References: <20200716131404.bnzsaarooumrp3kx@steredhat> <202007160751.ED56C55@keescook> <20200717080157.ezxapv7pscbqykhl@steredhat.lan> <39a3378a-f8f3-6706-98c8-be7017e64ddb@kernel.dk> <65ad6c17-37d0-da30-4121-43554ad8f51f@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-api-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org Hi, On 2020-07-21 12:44:09 -0700, Andy Lutomirski wrote: > Can you enlighten me? I don't see any iov_iter_get_pages() calls or > equivalents. If an IO is punted, how does the data end up in the > io_uring_enter() caller's mm? For operations needing that io_op_def.needs_mm is true. Which is checked by io_prep_async_work(), adding the current mm to req. On the wq side io_wq_switch_mm() uses that mm when executing the queue entry. Greetings, Andres Freund