From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.93]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E264D7F1 for ; Fri, 11 Aug 2023 01:53:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1691718830; x=1723254830; h=message-id:date:mime-version:cc:subject:to:references: from:in-reply-to:content-transfer-encoding; bh=J9wNibjtWigosqMiqT6RlANIRotnabaMtEYiNz739Ic=; b=RIjUsXX5cZ+T/2W5UBxzd5xpkOs1tTT7/7v6p9v1CYvOD6ba51H923L1 mz3iuRFxDnb9Q18csBetFKZ4HRuBs5P54orbVtpsgk4+vrhEPpgY5JJzN A+AUYzMmXTLCvwyzP86pTtBqCIMrrUq9vX1okX2lzWwgWaLP3wL36bD6m i69lOGJ7795WAyYKji/iicAdiz7Wsh9vP0ch6hII0RJqGFWoBRMGEqKoj hFu9NhCUad//rWPfPW+qiZbF3rEfM+MaEeu1SWJs6iqvvYV9MvcAbtWmW +813deOztl6cy5wcIUjAF7JCU+uhD4zEEiVqN0zukx2vwjGVVKRJEo10o w==; X-IronPort-AV: E=McAfee;i="6600,9927,10798"; a="369041739" X-IronPort-AV: E=Sophos;i="6.01,164,1684825200"; d="scan'208";a="369041739" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Aug 2023 18:53:49 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10798"; a="846618196" X-IronPort-AV: E=Sophos;i="6.01,164,1684825200"; d="scan'208";a="846618196" Received: from blu2-mobl.ccr.corp.intel.com (HELO [10.254.214.70]) ([10.254.214.70]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Aug 2023 18:53:46 -0700 Message-ID: Date: Fri, 11 Aug 2023 09:53:41 +0800 Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.14.0 Cc: baolu.lu@linux.intel.com, Joerg Roedel , Will Deacon , Robin Murphy , Jean-Philippe Brucker , Nicolin Chen , "Liu, Yi L" , Jacob Pan , "iommu@lists.linux.dev" , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v2 08/12] iommu: Prepare for separating SVA and IOPF Content-Language: en-US To: Jason Gunthorpe , "Tian, Kevin" References: <20230727054837.147050-1-baolu.lu@linux.intel.com> <20230727054837.147050-9-baolu.lu@linux.intel.com> <0771c28d-1b31-003e-7659-4f3f3cbf5546@linux.intel.com> From: Baolu Lu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2023/8/11 0:47, Jason Gunthorpe wrote: > On Thu, Aug 10, 2023 at 02:35:40AM +0000, Tian, Kevin wrote: >>> From: Baolu Lu >>> Sent: Wednesday, August 9, 2023 6:41 PM >>> >>> On 2023/8/9 8:02, Tian, Kevin wrote: >>>>> From: Jason Gunthorpe >>>>> Sent: Wednesday, August 9, 2023 2:43 AM >>>>> >>>>> On Thu, Aug 03, 2023 at 08:16:47AM +0000, Tian, Kevin wrote: >>>>> >>>>>> Is there plan to introduce further error in the future? otherwise this >>> should >>>>>> be void. >>>>>> >>>>>> btw the work queue is only for sva. If there is no other caller this can be >>>>>> just kept in iommu-sva.c. No need to create a helper. >>>>> I think more than just SVA will need a work queue context to process >>>>> their faults. >>>>> >>>> then this series needs more work. Currently the abstraction doesn't >>>> include workqueue in the common fault reporting layer. >>> Do you mind elaborate a bit here? workqueue is a basic infrastructure in >>> the fault handling framework, but it lets the consumers choose to use >>> it, or not to. >>> >> My understanding of Jason's comment was to make the workqueue the >> default path instead of being opted by the consumer.. that is my 1st >> impression but might be wrong... > Yeah, that is one path. Do we have anyone that uses this that doesn't > want the WQ? (actually who even uses this besides SVA?) I am still confused. When we forward iopf's to user space through the iommufd, we don't need to schedule a WQ, right? Or I misunderstood here? Best regards, baolu