linux-kernel - Re: random: GFP_KERNEL from irq context

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Date:   Thu, 26 Apr 2018 17:03:57 -0400
From:   "Theodore Y. Ts'o" <tytso@....edu>
To:     Jens Axboe <axboe@...nel.dk>
Cc:     jannh@...gle.com,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: random: GFP_KERNEL from irq context

On Thu, Apr 26, 2018 at 10:28:13AM -0600, Jens Axboe wrote:
> during boot. We end up doing the numa_crng_init() from interrupt context, which
> makes things unhappy since you do GFP_KERNEL | __GFP_NOFAIL allocations from
> there.

I've already sent a pull request to Linux to fix this; see the
random.git tree.

Apologies for not noticing this earlier.  My test environment had
virtio-rng enabled by default, and while I did test the CONFIG_NUMA
case, the call to add randomness doesn't happen from interrupt context
with virtio-rng so I missed it in my testing.

Cheers,

					- Ted