Re: [PATCH] hwrng: core - fix task hung in hwrng_fillfn

[Herbert Xu]

On Fri, Dec 01, 2023 at 08:34:12PM +0800, Edward Adam Davis wrote:
>
> According to splat, after a page fault occurred, the attempt to retrieve 
> rcu_read_lock() failed, resulting in a timeout of 143s. This is my speculation.

Oh I see what's going on.  The reproducer is mapping /dev/hwrng, so
the write to user-space is then triggering another read which then
dead-locks.

Let me think about this.

Thanks,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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