From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alejandro Lucero Subject: Re: [dpdk-users] IGB_UIO: PCI Resources Management Date: Fri, 13 Jan 2017 11:10:53 +0000 Message-ID: References: <3355891.l3I590SjcV@polaris> <608e7dfd-5226-3e30-f43b-0fbe01aee16a@intel.com> <7605618f-dc86-3060-473e-aff5545cac72@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: "Yigit, Ferruh" , Gregory Etelson , dev , "users@dpdk.org" To: "Tan, Jianfeng" Return-path: Received: from mail-ua0-f180.google.com (mail-ua0-f180.google.com [209.85.217.180]) by dpdk.org (Postfix) with ESMTP id 19AD2DE3 for ; Fri, 13 Jan 2017 12:17:52 +0100 (CET) Received: by mail-ua0-f180.google.com with SMTP id 96so34482928uaq.3 for ; Fri, 13 Jan 2017 03:17:52 -0800 (PST) In-Reply-To: List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" I completely misread the patch, and I wrongly thought that code was linked to module removal, but I see this is not about that, but about releasing the /dev/uio file calling release function, what is done by the kernel when the process exits. So yes, the patch avoids the problem I talked about. However, calling that specific ixgbe driver function will break other devices relying on igb_uio. What about implementing a notifier chain for this? The igb_uio code would be agnostic and each interested driver, like ixgbe or nfp_net, could execute the specific port close code when the notifier chain triggers. On Fri, Jan 13, 2017 at 5:33 AM, Tan, Jianfeng wrote: > > > > -----Original Message----- > > From: Yigit, Ferruh > > Sent: Friday, January 13, 2017 10:05 AM > > To: Tan, Jianfeng; Alejandro Lucero > > Cc: Gregory Etelson; dev; users@dpdk.org > > Subject: Re: [dpdk-users] [dpdk-dev] IGB_UIO: PCI Resources Management > > > > On 1/13/2017 1:51 AM, Tan, Jianfeng wrote: > > > > > > > > >> -----Original Message----- > > >> From: users [mailto:users-bounces@dpdk.org] On Behalf Of Ferruh Yigit > > >> Sent: Thursday, January 12, 2017 8:22 PM > > >> To: Alejandro Lucero > > >> Cc: Gregory Etelson; dev; users@dpdk.org > > >> Subject: Re: [dpdk-users] [dpdk-dev] IGB_UIO: PCI Resources > > Management > > >> > > >> On 1/12/2017 12:12 PM, Alejandro Lucero wrote: > > >>> > > >>> > > >>> On Thu, Jan 12, 2017 at 11:55 AM, Ferruh Yigit < > ferruh.yigit@intel.com > > >>> > wrote: > > >>> > > >>> On 12/9/2016 8:54 AM, Gregory Etelson wrote: > > >>> > Hello, > > >>> > > > >>> > IGB_UIO driver does not close port PCI activities after DPDK > process > > >> exits. > > >>> > DPDK API provides rte_eth_dev_close() to manage port PCI, > > >>> > but it can be skipped if process receives SIGKILL signal > > >>> > > >>> I guess I understand the problem. > > >>> > > >>> > > >>> This is a known problem, but it is not just a UIO problem, and this > > >>> patch does not solve it, maybe it just solves part of it. > > >>> > > >>> In fact, a DPDK program crashing could imply the NIC DMAing after > that > > >>> and after that memory was assigned to another program. > > >> > > >> Yes. > > >> Can there be a way to stop NIC DMA, (or prevent it access to mem > > >> anymore) when app crashes? > > >> I think that is what this patch is looking for. > > > > > > If I understand it correctly, you are looking for this patch? > > > http://dpdk.org/dev/patchwork/patch/17495/ > > > > > > > That is good, thanks Jianfeng, I will check it. > > > > btw, patch's current state is rejected, which is by mistake, it seems I > > confused it with "iomem and ioport mapping" patch, sorry about it, I > > will update its status immediately. > > No problem at all. This patch is rejected as it's based on "iomem and > ioport mapping" patch. As "iomem and ioport mapping" patch has backward > compatibility issue, we need to figure out a way to resubmit this patch > without changing the original "iomem and ioport mapping" in igb_uio. > > Thanks, > Jianfeng >