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Date: Wed, 23 Sep 2026 11:21:36 -0700
From: Oliver Upton <oupton@kernel.org>
To: Marc Zyngier <maz@kernel.org>
Cc: sashiko-reviews@lists.linux.dev, kvmarm@lists.linux.dev
Subject: Re: [PATCH 3/3] KVM: arm64: vgic: Stop the VM when disabling LPIs
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In-Reply-To: <86tsnf4zt8.wl-maz@kernel.org>

On Wed, Sep 23, 2026 at 06:56:03PM +0100, Marc Zyngier wrote:
> On Wed, 23 Sep 2026 17:41:53 +0100,
> Oliver Upton <oupton@kernel.org> wrote:
> > 
> > No issues with this approach but it is worth noting that all other
> > callers of kvm_arm_halt_guest() do so behind the config_lock today. You
> > could probably do the same with the LPI disable path.
> 
> Not quite. The IRQ bypass stuff doesn't know about the lock... But
> maybe we can fix it the same way. I'll investigate.
> 

Ah, right, good point.

On second thought, that'd require we hold the config_lock between
->stop() and ->start() on the irqbypass side of things and I'd prefer we
not externalize config_lock and how it ties into the locking hierarchy.

So ignore my feedback, I'm happy with the refcounting implementation.

Thanks,
Oliver