Re: [GIT PULL] Please Pull NFS Client Updates for Linux 7.0

[Niklas Cassel <cassel@kernel.org>]

On Thu, Feb 12, 2026 at 05:06:25PM -0500, Anna Schumaker wrote:
> Hi Linus,
> 
> The following changes since commit 24d479d26b25bce5faea3ddd9fa8f3a6c3129ea7:
> 
>   Linux 6.19-rc6 (2026-01-18 15:42:45 -0800)
> 
> are available in the Git repository at:
> 
>   git://git.linux-nfs.org/projects/anna/linux-nfs.git tags/nfs-for-7.0-1
> 
> for you to fetch changes up to dd2fdc3504592d85e549c523b054898a036a6afe:
> 
>   SUNRPC: fix gss_auth kref leak in gss_alloc_msg error path (2026-02-09 16:39:50 -0500)
> 
> ----------------------------------------------------------------
> NFS Client Updates for Linux 7.0
> 
> New Features:
>  * Use an LRU list for returning unused delegations
>  * Introduce a KConfig option to disable NFS v4.0 and make NFS v4.1 the default
> 
> Bugfixes:
>  * NFS/localio: Handle short writes by retrying
>  * NFS/localio: prevent direct reclaim recursion into NFS via nfs_writepages
>  * NFS/localio: use GFP_NOIO and non-memreclaim workqueue in nfs_local_commit
>  * NFS/localio: remove -EAGAIN handling in nfs_local_doio()
>  * pNFS: fix a missing wake up while waiting on NFS_LAYOUT_DRAIN
>  * fs/nfs: Fix a readdir slow-start regression
>  * SUNRPC: fix gss_auth kref leak in gss_alloc_msg error path
> 
> Other Cleanups and Improvements:
>   * A few other NFS/localio cleanups
>   * Various other delegation handling cleanups from Christoph
>   * Unify security_inode_listsecurity() calls
>   * Improvements to NFSv4 lease handling
>   * Clean up SUNRPC *_debug fields when CONFIG_SUNRPC_DEBUG is not set
> 
> Thanks,
> Anna

Hello Anna,

This seems to break my setup:

[  103.402033] VFS: Unable to mount root fs via NFS.
[  103.402476] devtmpfs: mounted
[  103.406171] Freeing unused kernel memory: 4352K
[  103.406633] Run /sbin/init as init process
[  103.406993]   with arguments:
[  103.407253]     /sbin/init
[  103.407491]   with environment:
[  103.407767]     HOME=/
[  103.407976]     TERM=linux
[  103.408228] Run /etc/init as init process
[  103.408580]   with arguments:
[  103.408841]     /etc/init
[  103.409071]   with environment:
[  103.409346]     HOME=/
[  103.409553]     TERM=linux
[  103.409802] Run /bin/init as init process
[  103.410153]   with arguments:
[  103.410414]     /bin/init
[  103.410644]   with environment:
[  103.410920]     HOME=/
[  103.411128]     TERM=linux
[  103.411367] Run /bin/sh as init process
[  103.411703]   with arguments:
[  103.411963]     /bin/sh
[  103.412179]   with environment:
[  103.412454]     HOME=/
[  103.412662]     TERM=linux
[  103.412904] Kernel panic - not syncing: No working init found.  Try passing init= option to kernel. See Linux Documentation/admin-guide/init.rst for guidance.


Doing a git bisect results in:

commit 4e0269352534715915aae3fb84dd4d3bb3ff3738
Author: Anna Schumaker <anna.schumaker@oracle.com>
Date:   Fri Nov 21 14:53:50 2025 -0500

    NFS: Add a way to disable NFS v4.0 via KConfig

    I introduce NFS4_MIN_MINOR_VERSION as a parallel to
    NFS4_MAX_MINOR_VERSION to check if NFS v4.0 has been compiled in and
    return an appropriate error if not.



Before commit above my config has:
CONFIG_NFS_FS=y
CONFIG_NFS_V4=y
CONFIG_NFS_V4_1=y
CONFIG_NFS_V4_2=y

after commit above (with make olddefconfig), my config has:
CONFIG_NFS_FS=y
CONFIG_NFS_V4=y
# CONFIG_NFS_V4_0 is not set
CONFIG_NFS_V4_1=y
CONFIG_NFS_V4_2=y



My kernel command line has:
nfsroot=192.168.1.10:/srv/nfs/rootfs,nfsvers=4


I notice that I am probably stupid who has the above, as I assumed that
it meant use the best NFS 4.x version supported by the kernel.


If I change it to:
nfsroot=192.168.1.10:/srv/nfs/rootfs,nfsvers=4.2

The config:
CONFIG_NFS_FS=y
CONFIG_NFS_V4=y
# CONFIG_NFS_V4_0 is not set
CONFIG_NFS_V4_1=y
CONFIG_NFS_V4_2=y

successfully mounts my rootfs.


So AFAICT, it seems that nfsvers=4 actually means nfsvers=4.0

I am probably not the only person to who has "nfsvers=4" on the kernel
command line.



Possible solutions I can see:

If the intention is for commit 4e0269352534 ("NFS: Add a way to disable
NFS v4.0 via KConfig") to allow people to disable NFS 4.0, we could
change the new "config NFS_V4_0" to be either "default y".

or

Perhaps we could modify "nfsvers=4" to actually mean "use whatever highest
NFS 4.x version supported by the kernel", rather than use NFS 4.0 and only
4.0.



Kind regards,
Niklas