From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 74658494832 for ; Fri, 4 Sep 2026 13:10:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788527411; cv=none; b=llOnzFkVWPKpPm525JBr99AMmW4X24PnPOnHaACYKMhd4fVkPwxu42xZP5juFfS/bwV2P5q++W4UT+uOKi7NRs7waQpaintgSxoSKHypYTXDbx2Qa+ylmYfMPFxSGvyakmqcB7rQYPhXQyQA+g35bu5jlbfolLlyHaruV36y77A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788527411; c=relaxed/simple; bh=07WAM1SfjOXKV0WA0TwbLd8Yy1QpCX1zVyf9xGCo5KI=; h=MIME-Version:Date:From:To:Cc:Message-Id:In-Reply-To:References: Subject:Content-Type; b=t2P53QKRqZjHk9Bp+60iducukaFA393aGjqqowoKRqNWFVeHOvhPFDdnWSbxNItWa1AfnB0VgPOb4XtxGPR65MOAG4Ba+yWAKTmGS8JIkm7VovwKiqjCA/lrOtTzukccYFwXOWUiLLO8CQ6ttomHo4YaqcXxNtD1/UUI5M/BnZE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Bf3MFPLM; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Bf3MFPLM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D96861F00A3F; Fri, 4 Sep 2026 13:10:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788527409; bh=07WAM1SfjOXKV0WA0TwbLd8Yy1QpCX1zVyf9xGCo5KI=; h=Date:From:To:Cc:In-Reply-To:References:Subject; b=Bf3MFPLMgJ2DQesHLlSJb9aDVkS+Usu6Q9leJY1kL6PenJ3MeVxglGqnWamkY0Xbm iXxAVKBZlcQLDGEMkqcQpciVoruoz++mOxfIMn5/+inwWhx/94x6k1TMyR2py1j1ui /A0Ki0AHm3ecdWS3E9MSMRqMQFPDPWwjAGYuKcyV9ZuD8avPkCms6Wtvo9lJ+ujjlc yR5ZmXv2q3r7tSAmvLgFAf/hTHQq+IBiQSVI6gyNYvZ0xF8JaFQpz2jA25Qlaq6S6G eKogJ/Cm//8lnpaokmL08lC7bh7HLiPyKAqtbbbD+dwe6ORq0QGNLdVrCG+bAMi0lf pRSvUgVMNVN0g== Received: from phl-compute-10.internal (phl-compute-10.internal [10.202.2.50]) by mailfauth.phl.internal (Postfix) with ESMTP id EAB6EF40066; Fri, 4 Sep 2026 09:10:07 -0400 (EDT) Received: from phl-imap-15 ([10.202.2.104]) by phl-compute-10.internal (MEProxy); Fri, 04 Sep 2026 09:10:07 -0400 X-ME-Sender: X-ME-Proxy-Cause: dmFkZTG3Hr5U8nL9jz62ZL93FO6z18bs2jb882+m+rBBuUiAAdw/C36HqM8Z6wp9AjT65u sG8zrQlSZD5cjtaGZ2czfNpbrQ+5rNQ+X93USqIweUdGNjOtehYLlCZyVIH015Dh41eCHW U6BTVR15G0bdyBQyFpPeYoSsrcRSVoIwWkCPwOzR4lfzAHR79uZanEfjD05EGT26m5v8/H 59hj9zsjFOAvP4dLyzHYUycKbzW3mX1pQng811ClDWg5fBXl+XgQ8vDKahIt06KoSVvT/8 xrdBbr9lWNklv87woii/HDVovmGRBHG3OdzoXugkOOhhzPdYcRC815E8MNKowdTR8/oJIa r4BmKijPvhwtROWW/7EdOt+fJapeKCOpOwxuH1d6XYdVcdYjtaXH/FFeBcvY95adTElqWu FKsVrG5vn/K8LslM2x0XMHiOcRWiFezo3/fkwdmAZBWFrEXH4zynD5twqMnwWw2QyNJoor UfwKl6on6iZO8eQG/l4JY1b8BLj0EFNuruLL7CYsNECqq5LDnF3wAdDoIXmeoGKXas0ybO rQokFy9H1ZsJgBFOfWoNHee2rtrgadaXD++cmTooxiexWFI+e82gmE8Yk9OO4L33I+yqaD K9V+Hb3BH3g50S8WV/Eh/0XnWEGTKfkQIuZIVxX0LJCYdzxePy9JPEskzdZA X-ME-Proxy: Feedback-ID: ifa6e4810:Fastmail Received: by mailuser.phl.internal (Postfix, from userid 501) id BFC8F7811F4; Fri, 4 Sep 2026 09:10:07 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ThreadId: AXS_LISVHZGo Date: Fri, 04 Sep 2026 09:09:47 -0400 From: "Chuck Lever" To: "Benji Wiebe" , "Jeff Layton" Cc: "Linux kernel regressions list" , linux-nfs@vger.kernel.org, stable@vger.kernel.org Message-Id: In-Reply-To: References: Subject: Re: [REGRESSION] reads and writes hang if NFS server has v3 disabled Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable [ Adding correct addresses from MAINTAINERS ] On Fri, Sep 4, 2026, at 9:05 AM, Chuck Lever wrote: > I'm using a minimal Fedora 45 VM (kvm) for testing.=E2=80=8A=C2=A0 I e= xport a > directory with rw and mount it from my personal computer running Fedora > 45 as well. If /etc/nfs.=E2=80=8Aconf has vers3=3Dn, then reads and wr= ites hang in > D+ state, and there's a continuous > > > I'm using a minimal Fedora 45 VM (kvm) for testing.=C2=A0 I export a=20 > directory with rw and mount it from my personal computer running Fedor= a=20 > 45 as well. > If /etc/nfs.conf has vers3=3Dn, then reads and writes hang in D+ state= ,=20 > and there's a continuous loop of V3 NULL calls, with the server replyi= ng=20 > that it only supports v4. > If nfs.conf has vers3=3Dy, then the reads and writes succeed. > Introduced in 70b7e3526c53d9dd, still present in the latest=20 > mainline/master (841e384b841a). > > The hung state can be rescued by changing the setting and restarting=20 > nfs-server, at which point the read/write will complete. > > I can do more testing / get more information as needed. > > Here's links to pcap files with it working/bugged: > http://grepper.net/lkml-files/nfs-working.pcap > http://grepper.net/lkml-files/nfs-bugged.pcap > http://grepper.net/lkml-files/nfs-bug-kernel.config > > #regzbot introduced:=C2=A0 70b7e3526c53d9dd7caccdbeff5b0485640d8cf1 It's not immediately obvious to me why 70b7e3526c53d9dd should cause this kind of behavior regression. Jeff, it's a netlink change. Can you triage? --=20 Chuck Lever (Come to NFS bake-a-thon! https://nfsv4bat.org)