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From: Milan Broz <gmazyland@gmail.com>
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Date: Fri, 19 Jul 2019 09:38:18 +0200
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Subject: Re: [dm-crypt] veritysetup forward error correction failure
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To: Tom Eccles <tom.eccles@codethink.co.uk>, dm-crypt@saout.de

On 18/07/2019 15:59, Tom Eccles wrote:
> 
> Should write access be required to the device be required? The kernel
> doesn't allow writable verity devices:

This is correct, verity devices must be read-only.

Anyway, I tried to run it again and this time I sometimes get error
and sometimes it recovers the device properly.

So there is something wrong inside kernel verity target, it could
be even two years old problem with switch to asynchronous crypto calls...

My losetup "workaround" probably just changed some timining, so
on your system it does not help. I'll investigate it :)

Anyway, thanks for reporting this!

Milan