[Bug 2062568] Re: nfsd gets unresponsive after some hours of operation

Wed Jan 22 23:06:00 UTC 2025

As another data point, we're seeing this bug on one of our NFS servers
running Ubuntu 24.04.1 with 6.8.0-51 kernel. Also experienced a similar
issue to one of the above users with unable to start nfs-kernel-server
and trying to restart the service.

[2164406.282362] INFO: task nfsd:8039 blocked for more than 122 seconds.
[2164406.282421]       Tainted: P           O       6.8.0-51-generic #52-Ubuntu
[2164406.282483] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[2164406.282547] task:nfsd            state:D stack:0     pid:8039  tgid:8039  ppid:2      flags:0x00004000
[2164406.282580] Call Trace:
[2164406.282585]  <TASK>
[2164406.282593]  __schedule+0x27c/0x6b0
[2164406.282612]  schedule+0x33/0x110
[2164406.282624]  io_schedule+0x46/0x80
[2164406.282636]  folio_wait_bit_common+0x136/0x330
[2164406.282654]  ? __pfx_wake_page_function+0x10/0x10
[2164406.282668]  folio_wait_bit+0x18/0x30
[2164406.282679]  folio_wait_writeback+0x2b/0xa0
[2164406.282695]  truncate_inode_partial_folio+0x81/0x180
[2164406.282715]  truncate_inode_pages_range+0x23a/0x530
[2164406.282746]  truncate_inode_pages_final+0x40/0x50
[2164406.282761]  evict+0x298/0x2b0
[2164406.282775]  ? vfs_getattr_nosec+0xb7/0x100
[2164406.282791]  ? vfs_getattr+0x4d/0x80
[2164406.282805]  iput+0x144/0x250
[2164406.282817]  nfsd_unlink+0x179/0x370 [nfsd]
[2164406.283053]  nfsd3_proc_remove+0x68/0xd0 [nfsd]
[2164406.283275]  nfsd_dispatch+0xd4/0x220 [nfsd]
[2164406.283495]  svc_process_common+0x4fd/0x750 [sunrpc]
[2164406.283794]  ? __pfx_nfsd_dispatch+0x10/0x10 [nfsd]
[2164406.284018]  svc_process+0x132/0x1b0 [sunrpc]
[2164406.284291]  svc_handle_xprt+0x4d3/0x5d0 [sunrpc]
[2164406.284558]  svc_recv+0x18b/0x2e0 [sunrpc]
[2164406.284788]  ? __pfx_nfsd+0x10/0x10 [nfsd]
[2164406.284986]  nfsd+0x8b/0xe0 [nfsd]
[2164406.285175]  kthread+0xef/0x120
[2164406.285186]  ? __pfx_kthread+0x10/0x10
[2164406.285196]  ret_from_fork+0x44/0x70
[2164406.285205]  ? __pfx_kthread+0x10/0x10
[2164406.285213]  ret_from_fork_asm+0x1b/0x30
[2164406.285225]  </TASK>

× nfs-server.service - NFS server and services
     Loaded: loaded (/usr/lib/systemd/system/nfs-server.service; enabled; preset: enabled)
    Drop-In: /run/systemd/generator/nfs-server.service.d
             └─order-with-mounts.conf
     Active: failed (Result: timeout) since Wed 2025-01-22 14:39:33 PST; 11min ago
   Duration: 1month 4d 18h 49min 1.130s
   Main PID: 8031 (code=exited, status=0/SUCCESS)
      Tasks: 2 (limit: 462611)
     Memory: 392.0K (peak: 524.0K)
        CPU: 3ms
     CGroup: /system.slice/nfs-server.service
             ├─3754609 /usr/sbin/rpc.nfsd 0
             └─3755576 /usr/sbin/exportfs -au

Jan 22 14:35:02 nfs-server systemd[1]: nfs-server.service: Processes still around after SIGKILL. Ignoring.
Jan 22 14:36:32 nfs-server systemd[1]: nfs-server.service: State 'stop-post' timed out. Terminating.
Jan 22 14:38:02 nfs-server systemd[1]: nfs-server.service: State 'final-sigterm' timed out. Killing.
Jan 22 14:38:02 nfs-server systemd[1]: nfs-server.service: Killing process 3755576 (exportfs) with signal SIGKILL.
Jan 22 14:38:02 nfs-server systemd[1]: nfs-server.service: Killing process 3754609 (rpc.nfsd) with signal SIGKILL.
Jan 22 14:39:33 nfs-server systemd[1]: nfs-server.service: Processes still around after final SIGKILL. Entering failed mode.
Jan 22 14:39:33 nfs-server systemd[1]: nfs-server.service: Failed with result 'timeout'.
Jan 22 14:39:33 nfs-server systemd[1]: nfs-server.service: Unit process 3754609 (rpc.nfsd) remains running after unit stopped.
Jan 22 14:39:33 nfs-server systemd[1]: nfs-server.service: Unit process 3755576 (exportfs) remains running after unit stopped.
Jan 22 14:39:33 nfs-server systemd[1]: Stopped nfs-server.service - NFS server and services.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to nfs-utils in Ubuntu.
https://bugs.launchpad.net/bugs/2062568

Title:
  nfsd gets unresponsive after some hours of operation

Status in linux package in Ubuntu:
  In Progress
Status in nfs-utils package in Ubuntu:
  Incomplete
Status in linux source package in Noble:
  In Progress
Status in nfs-utils source package in Noble:
  Incomplete

Bug description:
  I installed the 24.04 Beta on two test machines that were running
  22.04 without issues before. One of them exports two volumes that are
  mounted by the other machine, which primarily uses them as a secondary
  storage for ccache.

  After being up for a couple of hours (happened twice since yesterday
  evening) it seems that nfsd on the machine exporting the volumes hangs
  on something.

  From dmesg on the server (repeated a few times):

  [11183.290548] INFO: task nfsd:1419 blocked for more than 1228 seconds.
  [11183.290558]       Not tainted 6.8.0-22-generic #22-Ubuntu
  [11183.290563] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [11183.290582] task:nfsd            state:D stack:0     pid:1419  tgid:1419  ppid:2      flags:0x00004000
  [11183.290587] Call Trace:
  [11183.290602]  <TASK>
  [11183.290606]  __schedule+0x27c/0x6b0
  [11183.290612]  schedule+0x33/0x110
  [11183.290615]  schedule_timeout+0x157/0x170
  [11183.290619]  wait_for_completion+0x88/0x150
  [11183.290623]  __flush_workqueue+0x140/0x3e0
  [11183.290629]  nfsd4_probe_callback_sync+0x1a/0x30 [nfsd]
  [11183.290689]  nfsd4_destroy_session+0x186/0x260 [nfsd]
  [11183.290744]  nfsd4_proc_compound+0x3af/0x770 [nfsd]
  [11183.290798]  nfsd_dispatch+0xd4/0x220 [nfsd]
  [11183.290851]  svc_process_common+0x44d/0x710 [sunrpc]
  [11183.290924]  ? __pfx_nfsd_dispatch+0x10/0x10 [nfsd]
  [11183.290976]  svc_process+0x132/0x1b0 [sunrpc]
  [11183.291041]  svc_handle_xprt+0x4d3/0x5d0 [sunrpc]
  [11183.291105]  svc_recv+0x18b/0x2e0 [sunrpc]
  [11183.291168]  ? __pfx_nfsd+0x10/0x10 [nfsd]
  [11183.291220]  nfsd+0x8b/0xe0 [nfsd]
  [11183.291270]  kthread+0xef/0x120
  [11183.291274]  ? __pfx_kthread+0x10/0x10
  [11183.291276]  ret_from_fork+0x44/0x70
  [11183.291279]  ? __pfx_kthread+0x10/0x10
  [11183.291281]  ret_from_fork_asm+0x1b/0x30
  [11183.291286]  </TASK>

  From dmesg on the client (repeated a number of times):
  [ 6596.911785] RPC: Could not send backchannel reply error: -110
  [ 6596.972490] RPC: Could not send backchannel reply error: -110
  [ 6837.281307] RPC: Could not send backchannel reply error: -110

  ProblemType: Bug
  DistroRelease: Ubuntu 24.04
  Package: nfs-kernel-server 1:2.6.4-3ubuntu5
  ProcVersionSignature: Ubuntu 6.8.0-22.22-generic 6.8.1
  Uname: Linux 6.8.0-22-generic x86_64
  .etc.request-key.d.id_resolver.conf: create	id_resolver	*	*	/usr/sbin/nfsidmap -t 600 %k %d
  ApportVersion: 2.28.1-0ubuntu1
  Architecture: amd64
  CasperMD5CheckResult: pass
  Date: Fri Apr 19 14:10:25 2024
  InstallationDate: Installed on 2024-04-16 (3 days ago)
  InstallationMedia: Ubuntu-Server 24.04 LTS "Noble Numbat" - Beta amd64 (20240410.1)
  NFSMounts:

  NFSv4Mounts:

  ProcEnviron:
   LANG=en_US.UTF-8
   PATH=(custom, no user)
   SHELL=/bin/bash
   TERM=xterm-256color
   XDG_RUNTIME_DIR=<set>
  SourcePackage: nfs-utils
  UpgradeStatus: No upgrade log present (probably fresh install)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2062568/+subscriptions