From owner-freebsd-fs@freebsd.org Thu Feb 11 22:07:09 2021 Return-Path: Delivered-To: freebsd-fs@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 36B7353828A for ; Thu, 11 Feb 2021 22:07:09 +0000 (UTC) (envelope-from asomers@gmail.com) Received: from mail-ot1-f44.google.com (mail-ot1-f44.google.com [209.85.210.44]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Dc9hs0zX8z4trP for ; Thu, 11 Feb 2021 22:07:08 +0000 (UTC) (envelope-from asomers@gmail.com) Received: by mail-ot1-f44.google.com with SMTP id r21so6625964otk.13 for ; Thu, 11 Feb 2021 14:07:08 -0800 (PST) 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=4SYtiu02bfavKqlsWkWA5VSYLaRC6C3ln3NcN2VGoh0=; b=hiPnlv0/TfCygn2pvPKB1nIQ7UHxAkygvUAe3CclqEgkUfmbEBo1C5Gy76XS1bRiLx W9/GiHLNumB6yOm+sHxAnR5cxi2z3xCSkny7df2vIL30gfAgKgGD8EJ1HBDotPRqyJE4 4vZT3K4SDdJn1gwGjXOGGidaZg+UnIkhQovatTUxASDpDwcZErUvTt92YogAvKqC7EqJ nezvtRko4Y+E5Ngkl/QE6qHBBYerCr0BjVWLcimWb1UCrIXquFTVcpWscxN0JJ1xX4J1 AdPSOUlXqGF8h44BLrazhWwdw1dyv7U9rHnWpweAVFZ8R0oKwck5B1LLDWK60C4jv7ew Wi1w== X-Gm-Message-State: AOAM531cd8DzN7EBBMTUGzsha4RL5kJMcDXd88MLdU0kDYu/j7u+zXNB kSiJmffTyos7YMuAJxozg2LlRaNBzC2CRGANfbk= X-Google-Smtp-Source: ABdhPJxTkHcZnrBs4Z8QFADKEgoPD/qq2KsI1ZcSUZ38GK84iS/PuNeUol6lOr/zIXg++RDBEFHGGOVd4ZRzDP9yNsI= X-Received: by 2002:a05:6830:18e6:: with SMTP id d6mr90155otf.251.1613081228077; Thu, 11 Feb 2021 14:07:08 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Alan Somers Date: Thu, 11 Feb 2021 15:06:57 -0700 Message-ID: Subject: Re: NFS delegations don't expire after unmounting client To: Rick Macklem Cc: freebsd-fs X-Rspamd-Queue-Id: 4Dc9hs0zX8z4trP X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[] Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.34 X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 Feb 2021 22:07:09 -0000 On Thu, Feb 11, 2021 at 2:54 PM Rick Macklem wrote: > Alan Somers wrote: > >I have several Linux 5.9.15 clients mounting NFS 4.1 served from a FreeBSD > >12.2-RELEASE server. Today, most of those clients' mounts hung, and their > >dmesg displayed "nfs: server XXX not responding, still trying". > Usually these messages indicate a networking layer problem. > Next time (or if it still happening), check basic network connectivity. > Also, if any net interface does not handle TSO correctly for an RPC > message near 64Kbytes in size (the nasty one is where the NFS RPC is > less than 64K by less than 14bytes, so when the MAC layer header is > prepended, the total exceed 64K), you can get "stuck" TCP connections. > Most FreeBSD net chip drivers should be fixed for this, but I wouldn't be > surprised if there are some broken ones out there. > --> Disabling TSO fixes the problem in this case. In fact it is still happening. Basic network connectivity works. But tcpdump shows almost no network activity. Just a few keepalive packets of length 0-1. Based on the fact that unmount and even lsof hang on the client, I'm suspecting a Linux bug somewhere. -Alan