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Date:   Tue, 1 Sep 2020 06:21:27 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Qian Cai <cai@lca.pw>
Cc:     darrick.wong@oracle.com, hch@infradead.org,
        linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4] iomap: fix WARN_ON_ONCE() from unprivileged users
Message-ID: <20200901052127.GA24560@infradead.org>
References: <20200831182353.14593-1-cai@lca.pw>
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On Mon, Aug 31, 2020 at 02:23:53PM -0400, Qian Cai wrote:
> It is trivial to trigger a WARN_ON_ONCE(1) in iomap_dio_actor() by
> unprivileged users which would taint the kernel, or worse - panic if
> panic_on_warn or panic_on_taint is set. Hence, just convert it to
> pr_warn_ratelimited() to let users know their workloads are racing.
> Thank Dave Chinner for the initial analysis of the racing reproducers.
> 
> Signed-off-by: Qian Cai <cai@lca.pw>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>