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Date:   Tue, 4 Jun 2019 09:16:07 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
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,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Marc Zyngier <marc.zyngier@arm.com>, julia@ni.com
Subject: Re: KVM Arm Device passthrough and linux-rt
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On Tue, 4 Jun 2019 13:58:51 +0100
Julien Grall <julien.grall@arm.com> wrote:

> 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?

What's the reason that vgic_v2_fold_lr_state() expects interrupts to be
disabled?

-- Steve