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Date:   Sat, 20 Jun 2020 11:23:33 +1000
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Mikulas Patocka <mpatocka@redhat.com>
Cc:     Ignat Korchagin <ignat@cloudflare.com>,
        "David S. Miller" <davem@davemloft.net>,
        Mike Snitzer <snitzer@redhat.com>, agk@redhat.com,
        dm-devel@redhat.com, dm-crypt@saout.de,
        linux-kernel@vger.kernel.org, kernel-team@cloudflare.com
Subject: Re: [RFC PATCH 0/1] dm-crypt excessive overhead
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On Fri, Jun 19, 2020 at 02:39:39PM -0400, Mikulas Patocka wrote:
>
> I'm looking at this and I'd like to know why does the crypto API fail in 
> hard-irq context and why does it work in tasklet context. What's the exact 
> reason behind this?

You're not supposed to do any real work in IRQ handlers.  All
the substantial work should be postponed to softirq context.

Why do you need to do work in hard IRQ context?

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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