linux-kernel - Re: [PATCH v2 0/2] Fix vm.dirtytime_expire

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Message-ID: <20260112-erlesen-befanden-3f875582b84d@brauner>
Date: Mon, 12 Jan 2026 11:07:50 +0100
From: Christian Brauner <brauner@...nel.org>
To: Laveesh Bansal <laveeshb@...eeshbansal.com>
Cc: Christian Brauner <brauner@...nel.org>,
	jack@...e.cz,
	tytso@....edu,
	linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	stable@...r.kernel.org,
	viro@...iv.linux.org.uk
Subject: Re: [PATCH v2 0/2] Fix vm.dirtytime_expire_seconds=0 causing 100% CPU

On Tue, 06 Jan 2026 14:50:57 +0000, Laveesh Bansal wrote:
> Setting vm.dirtytime_expire_seconds to 0 causes wakeup_dirtytime_writeback()
> to reschedule itself with a delay of 0, creating an infinite busy loop that
> spins kworker at 100% CPU.
> 
> This series:
> - Patch 1: Fixes the bug by handling interval=0 as "disable writeback"
>            (consistent with dirty_writeback_centisecs behavior)
> - Patch 2: Documents that setting the value to 0 disables writeback
> 
> [...]

Applied to the vfs.fixes branch of the vfs/vfs.git tree.
Patches in the vfs.fixes branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.fixes

[1/2] writeback: fix 100% CPU usage when dirtytime_expire_interval is 0
      https://git.kernel.org/vfs/vfs/c/543467d6fe97
[2/2] docs: clarify that dirtytime_expire_seconds=0 disables writeback
      https://git.kernel.org/vfs/vfs/c/30ef9a20f1fd