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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA946C433F5 for ; Thu, 28 Apr 2022 16:35:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350140AbiD1Qi6 (ORCPT ); Thu, 28 Apr 2022 12:38:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35654 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350097AbiD1Qi4 (ORCPT ); Thu, 28 Apr 2022 12:38:56 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE398888E5 for ; Thu, 28 Apr 2022 09:35:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1651163741; x=1682699741; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=rcuXjMkF8Ip+u/ASCnj8P5Cfp+tPtitJogFYRQ+vRQI=; b=Ieqge3cD1txlnLf43ldDIubkq3I5rjwrXh0jgK7YyJyHvsAI1jDfZhMb B/g8OOcOX8JsXYzMXGZqsoP9OFInVCloO3woMy0szNRIC7HyZrQAtly7d I4P4+tTiFZz9WQN50z2U0AJmtyzGmfTUi/C9jZdyzdMoFOJHlZvX/2SOs epcQLkuctpf/ue2YFZ8v4LBiG2cZ3yTFCm8jKzITGi+ONs9asmtNdRswT f8WZZpUFilrhY/95uUcVtc5OGOZHE1Xhrh2nymVLUDqu+gDGY704fQ4TC xWhPEmRAhNoVrOvQONH8CvpJUino1xuTAUgtVsPm3aIE5vJJtBLcvd+os Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10331"; a="266160097" X-IronPort-AV: E=Sophos;i="5.91,295,1647327600"; d="scan'208";a="266160097" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Apr 2022 09:35:24 -0700 X-IronPort-AV: E=Sophos;i="5.91,295,1647327600"; d="scan'208";a="559761235" Received: from mpoursae-mobl2.amr.corp.intel.com (HELO [10.212.0.84]) ([10.212.0.84]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Apr 2022 09:35:22 -0700 Message-ID: <7ad996df-28ca-0aee-be23-e75bcca8d136@intel.com> Date: Thu, 28 Apr 2022 09:35:39 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH v4 05/11] iommu/sva: Assign a PASID to mm on PASID allocation and free it on mm exit Content-Language: en-US To: Jean-Philippe Brucker Cc: Fenghua Yu , Jacob Pan , Tony Luck , Ashok Raj , Ravi V Shankar , Peter Zijlstra , robin.murphy@arm.com, Dave Hansen , x86 , linux-kernel , iommu , Ingo Molnar , Borislav Petkov , Andy Lutomirski , Josh Poimboeuf , zhangfei.gao@linaro.org, Thomas Gleixner , will@kernel.org References: <76ec6342-0d7c-7c7b-c132-2892e4048fa1@intel.com> <20220425083444.00af5674@jacob-builder> From: Dave Hansen In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/28/22 09:01, Jean-Philippe Brucker wrote: >> But, this misses an important point: even after the address space is >> gone, the PASID will still be programmed into a device. Device drivers >> might, for instance, still need to flush operations that are outstanding >> and need to use that PASID. They do this at ->release() time. > It's not really clear which release() this is. For us it's file descriptor > release() (not MMU notifier release(), which is how I initially understood > this sentence) OK, maybe that should be: "file->release() time" to make it more clear.