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Subject: Re: [PATCH kernel v3] genirq/irqdomain: Add reference counting to
 IRQs
To:     Alexey Kardashevskiy <aik@ozlabs.ru>, Marc Zyngier <maz@kernel.org>
Cc:     linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        =?UTF-8?Q?C=c3=a9dric_Le_Goater?= <clg@kaod.org>,
        Michael Ellerman <mpe@ellerman.id.au>, Qian Cai <cai@lca.pw>,
        Rob Herring <robh@kernel.org>,
        =?UTF-8?Q?Michal_Such=c3=a1nek?= <msuchanek@suse.de>
References: <20201109094646.71565-1-aik@ozlabs.ru>
 <fac73255eabb43242528821888acf2cc@kernel.org>
 <98d06682-da53-c851-74a7-952bf958b793@ozlabs.ru>
From:   Frederic Barrat <fbarrat@linux.ibm.com>
Message-ID: <e552f6a9-8b82-f446-d67d-2f666870c766@linux.ibm.com>
Date:   Sat, 14 Nov 2020 10:42:18 +0100
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On 14/11/2020 04:37, Alexey Kardashevskiy wrote:

>> I'll try to go through this patch over the week-end (or more probably
>> early next week), and try to understand where our understandings
>> differ.
> 
> Great, thanks! Fred spotted a problem with irq_free_descs() not doing 
> kobject_put() anymore and this is a problem for sa1111.c and the likes 
> and I will go though these places anyway.

So there are callers out there which don't care about mapping the 
interrupt. Wouldn't it be easier to leave alone the kobject from the irq 
descriptor (my understanding is that it's there to handle the sysfs 
representation) and add a simple kref counter, just to handle the 
mapping part?

   Fred