linux-ext4 - Re: File name is not persisted if opened with O_SYNC and O

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Message-ID: <aY7T1LS5vnZI-ZxE@infradead.org>
Date: Thu, 12 Feb 2026 23:33:40 -0800
From: Christoph Hellwig <hch@...radead.org>
To: Vyacheslav Kovalevsky <slava.kovalevskiy.2014@...il.com>
Cc: viro@...iv.linux.org.uk, brauner@...nel.org,
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-btrfs@...r.kernel.org, linux-ext4@...r.kernel.org
Subject: Re: File name is not persisted if opened with O_SYNC and O_TRUNC
 flags

On Thu, Feb 12, 2026 at 02:51:47PM +0300, Vyacheslav Kovalevsky wrote:
> Detailed description
> ====================
> 
> Hello, there seems to be an issue with O_SYNC flag when used together with
> O_TRUNC on various file systems.
> Opening a file with O_SYNC (or using fsync(fd)) should persist directory
> entry.

No, it should not.  I'm not sure who hallucinated, but O_SYNC has always
always applied to persistency semantics after writes and nothing else.