From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alejandro Lucero Subject: Re: [PATCH v3 0/6] use IOVAs check based on DMA mask Date: Mon, 29 Oct 2018 09:25:48 +0000 Message-ID: References: <1538743527-8285-1-git-send-email-alejandro.lucero@netronome.com> <2DBBFF226F7CF64BAFCA79B681719D954502B75A@shsmsx102.ccr.corp.intel.com> <1593678.TTmrtHRuFR@xps> <55033937.TxNRu7Uagg@xps> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: lei.a.yao@intel.com, dev , "Xu, Qian Q" , xueqin.lin@intel.com, "Burakov, Anatoly" , Ferruh Yigit , Bruce Richardson To: Thomas Monjalon Return-path: Received: from mail-ed1-f44.google.com (mail-ed1-f44.google.com [209.85.208.44]) by dpdk.org (Postfix) with ESMTP id 437EA1F1C for ; Mon, 29 Oct 2018 10:26:00 +0100 (CET) Received: by mail-ed1-f44.google.com with SMTP id t10-v6so6608194eds.12 for ; Mon, 29 Oct 2018 02:26:00 -0700 (PDT) In-Reply-To: <55033937.TxNRu7Uagg@xps> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Can we have the configuration triggering this issue? On Mon, Oct 29, 2018 at 9:07 AM Thomas Monjalon wrote: > One more comment about this issue, > > There was no reply to the question asked by Alejandro on October 11th: > http://mails.dpdk.org/archives/dev/2018-October/115402.html > and there were no more reviews despite all my requests: > http://mails.dpdk.org/archives/dev/2018-October/117475.html > Without any more comment, I had to apply the patchset. > > Now we need to find a solution. Please suggest. > > > 29/10/2018 09:42, Thomas Monjalon: > > 29/10/2018 09:23, Yao, Lei A: > > > Hi, Lucero, Thomas > > > > > > This patch set will cause deadlock during memory initialization. > > > rte_memseg_walk and try_expand_heap both will lock > > > the file &mcfg->memory_hotplug_lock. So dead lock will occur. > > > > > > #0 rte_memseg_walk > > > #1 <-rte_eal_check_dma_mask > > > #2 <-alloc_pages_on_heap > > > #3 <-try_expand_heap_primary > > > #4 <-try_expand_heap > > > > > > Log as following: > > > EAL: TSC frequency is ~2494156 KHz > > > EAL: Master lcore 0 is ready (tid=7ffff7fe3c00;cpuset=[0]) > > > [New Thread 0x7ffff5e0d700 (LWP 330350)] > > > EAL: lcore 1 is ready (tid=7ffff5e0d700;cpuset=[1]) > > > EAL: Trying to obtain current memory policy. > > > EAL: Setting policy MPOL_PREFERRED for socket 0 > > > EAL: Restoring previous memory policy: 0 > > > > > > Could you have a check on this? A lot of test cases in our validation > > > team fail because of this. Thanks a lot! > > > > Can we just call rte_memseg_walk_thread_unsafe()? > > > > +Cc Anatoly > > > > > > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Thomas Monjalon > > > > 05/10/2018 14:45, Alejandro Lucero: > > > > > I sent a patchset about this to be applied on 17.11 stable. The > memory > > > > > code has had main changes since that version, so here it is the > patchset > > > > > adjusted to current master repo. > > > > > > > > > > This patchset adds, mainly, a check for ensuring IOVAs are within a > > > > > restricted range due to addressing limitations with some devices. > There > > > > > are two known cases: NFP and IOMMU VT-d emulation. > > > > > > > > > > With this check IOVAs out of range are detected and PMDs can abort > > > > > initialization. For the VT-d case, IOVA VA mode is allowed as long > as > > > > > IOVAs are within the supported range, avoiding to forbid IOVA VA by > > > > > default. > > > > > > > > > > For the addressing limitations known cases, there are just 40(NFP) > or > > > > > 39(VT-d) bits for handling IOVAs. When using IOVA PA, those > limitations > > > > > imply 1TB(NFP) or 512M(VT-d) as upper limits, which is likely > enough for > > > > > most systems. With machines using more memory, the added check will > > > > > ensure IOVAs within the range. > > > > > > > > > > With IOVA VA, and because the way the Linux kernel serves mmap > calls > > > > > in 64 bits systems, 39 or 40 bits are not enough. It is possible to > > > > > give an address hint with a lower starting address than the > default one > > > > > used by the kernel, and then ensuring the mmap uses that hint or > hint plus > > > > > some offset. With 64 bits systems, the process virtual address > space is > > > > > large enoguh for doing the hugepages mmaping within the supported > > > > range > > > > > when those addressing limitations exist. This patchset also adds a > change > > > > > for using such a hint making the use of IOVA VA a more than likely > > > > > possibility when there are those addressing limitations. > > > > > > > > > > The check is not done by default but just when it is required. This > > > > > patchset adds the check for NFP initialization and for setting the > IOVA > > > > > mode is an emulated VT-d is detected. Also, because the recent > patchset > > > > > adding dynamic memory allocation, the check is also invoked for > ensuring > > > > > the new memsegs are within the required range. > > > > > > > > > > This patchset could be applied to stable 18.05. > > > > > > > > Applied, thanks > > > >