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Date:   Tue, 4 Jun 2019 15:50:48 +0200
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Julien Grall <julien.grall@arm.com>
Cc:     linux-rt-users <linux-rt-users@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        kvmarm@lists.cs.columbia.edu, Marc Zyngier <marc.zyngier@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>, julia@ni.com
Subject: Re: KVM Arm Device passthrough and linux-rt
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On 2019-06-04 13:58:51 [+0100], Julien Grall wrote:
> Hi,
Hi,

> This is happening because vgic_v2_fold_lr_state() is expected
> to be called with interrupt disabled. However, some of the path
> (e.g eventfd) will take a spinlock.
> 
> The spinlock is from the waitqueue, so using a raw_spin_lock cannot
> even be considered.
> 
> Do you have any input on how this could be solved?

There is swair (init_swait_queue_head() and friends) in case that works
for you.

> Cheers,

Sebastian