Arch Linux

fofe1123

Member

Registered: 2025-02-07

Posts: 1

Btrfs: Filesystem remounted Read-Only with no apparent reason

Hello everyone,

Today I encountered an issue with my Arch Linux system running on Btrfs. While working (specifically during an exam), my system suddenly remounted the filesystem in read-only mode due to a corruption error. However, after running diagnostics, I couldn’t find any actual issues with the filesystem, nor the disk.

System Information:

• Distro: Arch Linux (fully updated)

• Kernel: 6.13.1-zen

• Filesystem: Btrfs (on a single NVMe SSD, no RAID)

What Happened:

• The system became read-only without any apparent cause.

• Checking dmesg I found the following log:

  [Fri Feb  7 19:02:58 2025] BTRFS info (device nvme0n1p3): bdev /dev/nvme0n1p3 errs: wr 0, rd 0, flush 0, corrupt 1, gen 0

• Running

  btrfs device stats /

  also reported:

  bdev /dev/nvme0n1p3 errs: wr 0, rd 0, flush 0, corrupt 1, gen 0

However, a full

 btrfs scrub 

completed successfully with no error reported. 
Running

btrfs check --readonly --force /dev/nvme0n1p3

found no corruption. 

smartctl

also reports no issues with the drive. 
It seems also that the filesystem tree was regenerated at the next boot.

Possible Theories:

• A transient issue with the Btrfs log tree that caused a false positive corruption report.

• A kernel bug affecting Btrfs.

• An inconsistency that was resolved by the log replay at mount time.

• A temporary problem with the SSD firmware or cache that did not persist.

Questions:

• Has anyone else experienced similar behavior?

• Could this be a known issue with the kernel / Btrfs?

• Are there any additional checks I should run to further diagnose the cause?

I’d appreciate any insights! Thanks in advance.

Last edited by fofe1123 (2025-02-07 20:49:14)

seth

Member

Registered: 2012-09-03

Posts: 64,179

Re: Btrfs: Filesystem remounted Read-Only with no apparent reason

Trimming (discard mount option) or APST caused?
Are there any errors pertaining the nvme in the journal?

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okram

Member

Registered: 2019-01-24

Posts: 3

Re: Btrfs: Filesystem remounted Read-Only with no apparent reason

I've had this problem for a long time (over a year). Over time I've tried very many different solution candidates: so far nothing has worked. What makes this very hard for me to debug is the fact that my system is btrfs-only. So, when it happens: no logs...

Edit: I often see this upon resume.

Last edited by okram (2025-02-18 15:42:46)