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	Tue, 19 Nov 2024 16:22:08 +0000
Date: Tue, 19 Nov 2024 08:22:08 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
	linux-api@vger.kernel.org
Subject: Re: [PATCH] uapi: add EROBLK
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References: <9184b5e8-7070-4395-b179-4975b2e3fbc3@p183>
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On Tue, Nov 19, 2024 at 06:54:52PM +0300, Alexey Dobriyan wrote:
> Block drivers and DM sometimes use EROFS to report errors. There is
> no confusion about what happens but naive error reporting code might
> pass -EROFS to strerror(3) which will print "filesystem" when clearly
> there is no filesystem anywhere, it is layer above.
> 
> Or in other words, if EROFS exists, why not EROBLK?
> It is not like there is a tax on errno values.

And where would you return this value without breaking existing
userspace?