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Date:   Thu, 24 Dec 2020 07:56:42 +1100
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>
Cc:     Ignat Korchagin <ignat@cloudflare.com>, agk@redhat.com,
        snitzer@redhat.com, dm-devel@redhat.com, dm-crypt@saout.de,
        linux-kernel@vger.kernel.org, ebiggers@kernel.org,
        Damien.LeMoal@wdc.com, mpatocka@redhat.com,
        kernel-team@cloudflare.com, nobuto.murata@canonical.com,
        Chris Mason <clm@fb.com>, Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>, linux-btrfs@vger.kernel.org,
        linux-crypto <linux-crypto@vger.kernel.org>
Subject: Re: dm-crypt with no_read_workqueue and no_write_workqueue + btrfs
 scrub = BUG()
Message-ID: <20201223205642.GA19817@gondor.apana.org.au>
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 <74c7129b-a437-ebc4-1466-7fb9f034e006@maciej.szmigiero.name>
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On Wed, Dec 23, 2020 at 04:37:34PM +0100, Maciej S. Szmigiero wrote:
> 
> It looks like to me that the skcipher API might not be safe to
> call from a softirq context, after all.

skcipher is safe to use in a softirq.  The problem is only in
dm-crypt where it tries to allocate memory with GFP_NOIO.

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