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	Fri, 05 Jun 2026 07:31:28 +0000
Date: Fri, 5 Jun 2026 00:31:27 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Wentao Liang <vulab@iscas.ac.cn>
Cc: axboe@kernel.dk, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] block/fops: fix refcount underflow in
 __blkdev_direct_IO()
Message-ID: <aiJ7T7M2v7x9jGsJ@infradead.org>
References: <20260603021035.3690601-1-vulab@iscas.ac.cn>
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On Wed, Jun 03, 2026 at 02:10:35AM +0000, Wentao Liang wrote:
> __blkdev_direct_IO() calls bio_get() and bio_put() around
> I/O operations, but if the I/O fails, the error path may call
> bio_put() twice, causing a refcount underflow.

What I/O failure do you observe?