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Date: Thu, 18 Apr 2024 08:28:01 +0200
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Subject: Re: API break, sysfs "capability" file
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To: Christoph Hellwig <hch@lst.de>, Lennart Poettering <mzxreary@0pointer.de>
Cc: Keith Busch <kbusch@kernel.org>,
 Linux regressions mailing list <regressions@lists.linux.dev>,
 linux-block@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
 Jens Axboe <axboe@kernel.dk>
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From: Hannes Reinecke <hare@suse.de>
In-Reply-To: <20240417155913.GA6447@lst.de>
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On 4/17/24 17:59, Christoph Hellwig wrote:
> On Wed, Apr 17, 2024 at 05:48:16PM +0200, Lennart Poettering wrote:
>> Block devices with part scanning off are quite common after all,
>> i.e. "losetup" creates them by default like that, and partition block
>> devices themselves have no part scanning on and so on, hence we have
>> to be ablet to operate sanely with them.
> 
> Maybe and ioctl to turn on partition scanning if it is currently disabled
> or return an error otherwise would be the better thing?  It would
> do the right thing for the most common loop case, and with a bit more
> work could do the right thing for those that more or less disable it
> graciously (ubiblock, drbd, zram) and would just fail for those who are
> so grotty old code and slow devices that we never want to do a partition
> scan (basically old floppy drivers and the Nintendo N64 cartridge driver)
> 
> 
The world is going to end.
hch suggests an ioctl.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich