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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 BADE3CA9EA0 for ; Sat, 19 Oct 2019 00:34:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D9BE222C5 for ; Sat, 19 Oct 2019 00:34:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=umich.edu header.i=@umich.edu header.b="iS/0lLRn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732071AbfJSAeX (ORCPT ); Fri, 18 Oct 2019 20:34:23 -0400 Received: from mail-ua1-f65.google.com ([209.85.222.65]:40489 "EHLO mail-ua1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731848AbfJSAeX (ORCPT ); Fri, 18 Oct 2019 20:34:23 -0400 Received: by mail-ua1-f65.google.com with SMTP id i13so2355517uaq.7 for ; Fri, 18 Oct 2019 17:34:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=umich.edu; s=google-2016-06-03; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=DSRZtDmaYjduYVd72orzJ0tXlEEEXpzwX1qMU+dlU/8=; b=iS/0lLRn1UKTR+XsNn8brGs81piUUpdbh7oI6MjxgxYpr85M/Lxkcn2i8AH2qGhxRx oq70L3kq4Lmv7Ah3DNyr7dMBo3OseyoZhn/5QxFJEPNInZ33JnP0UoAoFM1eNiwtd+o3 Wape5J6fXwUhRG7DmqJXKecP6g5sFUlptnSeWjvp3q1+YVm10rhtun/MWT6MRs1QzAgI a7hW1NArPfD2ohIMd1z4pugqMvFE3pBwARjBgPKOtNNp3Fn4hQ7npve5LYTOntK5lwGL TQPsp/un2lNQu9X8h8jU4sreM64E7vFaEWc3A4GRRRpPNlmZC654f20ElSxEgbO8rjMT YnPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=DSRZtDmaYjduYVd72orzJ0tXlEEEXpzwX1qMU+dlU/8=; b=Vw3Jbad9EgH9G7YfmnJUXFVKM0trpBPhN9hdMtQBGlAknxgkus09VwgPRNXbDYQXLR +tzra9IeG35Vep2YyDw8aoWftm4Nyj0PGR7FAqIqLEl40AZsJ9ITuf1LE7ENL+GPvTTe zyQJs2NsnvNmqeaeOUZrz7QNMvoJTVjTBBa2V4wJrwoW0OcFhL6j42p2AqvHLfRF6I8/ SRNg5yd0vJjtXaX1GpZ+w/YzmiAAxRKxci4Rm2+DEo2WVQVUBM8tvViTf8YE2ubv2AB/ aW5S+ubboBvVnzx47l46clSt9vVImpyz2NpBVZDAt7GW5UAGK4t8iZ989WjfShnxJEyS kAcg== X-Gm-Message-State: APjAAAWhF7BrAb79PJjI2s5Sz8SOTXrhvvEJs1FyG+XkYD+WxfMFskcx 6JC7ctnpxXsqLfZkEfnqBqvg+UBPXOSOCSkkZzg= X-Google-Smtp-Source: APXvYqymPWW38L4lLa9cr0HRi95aJmSr+DncrVw7uJVmxQ1L8m+q1mSZbWkeRKwjrHTJqWJoUAtcoXLUJsiFvF8NQIc= X-Received: by 2002:a9f:3673:: with SMTP id s48mr6952849uad.119.1571445260408; Fri, 18 Oct 2019 17:34:20 -0700 (PDT) MIME-Version: 1.0 References: <20191010074020.o2uwtuyegtmfdlze@XZHOUW.usersys.redhat.com> <2597b15558e1195436db68f019899694c796fef6.camel@hammerspace.com> In-Reply-To: From: Olga Kornievskaia Date: Fri, 18 Oct 2019 20:34:09 -0400 Message-ID: Subject: Re: [PATCH] NFSv4: fix stateid refreshing when CLOSE racing with OPEN To: Trond Myklebust Cc: "jencce.kernel@gmail.com" , "linux-nfs@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Fri, Oct 11, 2019 at 2:50 PM Olga Kornievskaia wrote: > > On Fri, Oct 11, 2019 at 10:18 AM Trond Myklebust > wrote: > > > > On Thu, 2019-10-10 at 13:32 -0400, Olga Kornievskaia wrote: > > > On Thu, Oct 10, 2019 at 3:42 AM Murphy Zhou > > > wrote: > > > > Since commit: > > > > [0e0cb35] NFSv4: Handle NFS4ERR_OLD_STATEID in > > > > CLOSE/OPEN_DOWNGRADE > > > > > > > > xfstests generic/168 on v4.2 starts to fail because reflink call > > > > gets: > > > > +XFS_IOC_CLONE_RANGE: Resource temporarily unavailable > > > > > > I don't believe this failure has to do with getting ERR_OLD_STATEID > > > on > > > the CLOSE. What you see on the network trace is expected as the > > > client > > > in parallel sends OPEN/CLOSE thus server will fail the CLOSE with the > > > ERR_OLD_STATEID since it already updated its stateid for the OPEN. > > > > > > > In tshark output, NFS4ERR_OLD_STATEID stands out when comparing > > > > with > > > > good ones: > > > > > > > > 5210 NFS 406 V4 Reply (Call In 5209) OPEN StateID: 0xadb5 > > > > 5211 NFS 314 V4 Call GETATTR FH: 0x8d44a6b1 > > > > 5212 NFS 250 V4 Reply (Call In 5211) GETATTR > > > > 5213 NFS 314 V4 Call GETATTR FH: 0x8d44a6b1 > > > > 5214 NFS 250 V4 Reply (Call In 5213) GETATTR > > > > 5216 NFS 422 V4 Call WRITE StateID: 0xa818 Offset: 851968 Len: > > > > 65536 > > > > 5218 NFS 266 V4 Reply (Call In 5216) WRITE > > > > 5219 NFS 382 V4 Call OPEN DH: 0x8d44a6b1/ > > > > 5220 NFS 338 V4 Call CLOSE StateID: 0xadb5 > > > > 5222 NFS 406 V4 Reply (Call In 5219) OPEN StateID: 0xa342 > > > > 5223 NFS 250 V4 Reply (Call In 5220) CLOSE Status: > > > > NFS4ERR_OLD_STATEID > > > > 5225 NFS 338 V4 Call CLOSE StateID: 0xa342 > > > > 5226 NFS 314 V4 Call GETATTR FH: 0x8d44a6b1 > > > > 5227 NFS 266 V4 Reply (Call In 5225) CLOSE > > > > 5228 NFS 250 V4 Reply (Call In 5226) GETATTR > > > > > > "resource temporarily unavailable" is more likely to do with ulimit > > > limits. > > > > > > I also saw the same error. After I increased the ulimit for the stack > > > size, the problem went away. There might still be a problem somewhere > > > in the kernel. > > > > > > Trond, is it possible that we have too many CLOSE recovery on the > > > stack that's eating up stack space? > > > > That shouldn't normally happen. CLOSE runs as an asynchronous RPC call, > > so its stack usage should be pretty minimal (limited to whatever each > > callback function uses). > > Yeah, that wasn't it. I've straced generic/168 to catch > ioctl(clone_file_range) returning EAGAIN. > > I've instrumented the kernel to see where we are returning an EAGAIN > in nfs42_proc_clone(). nfs42_proc_clone is failing on > nfs42_select_rw_context() because nfs4_copy_open_stateid() is failing > to get the open state. Basically it looks like we are trying to do a > clone on a file that's not opened. Still trying to understand > things... Trond, Generic/168 fails in 2 ways (though only 1 leads to the failure in xfs_io). Another way is having a file closed then client using the stateid for the write and getting a bad_stateid which the client recovers from (but the fact that client shouldn't have done that is a problem). Another is the clone where again happens that file is "closed" and clone is trying to use a stateid. The problem comes from the following fact. We have a racing CLOSE and OPEN. Where client did the CLOSE followed by the OPEN but the server processed OPEN and then the CLOSE. Server returns OLD_STATEID to the CLOSE. What the code does it bumps the sequence id and resends the CLOSE which inadvertently is closing a file that was opened before. While IO errors from this are recoverable, the clone error is visible to the application (I think another case would be a copy). I don't have a code solution yet. But it'll have to be something where we need to ignore a CLOSE with OLD_STATEID when another OPEN happened.