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Date:   Thu, 19 Jan 2023 18:14:44 +0000
From:   Will Deacon <will@kernel.org>
To:     Geoff Blake <blakgeof@amazon.com>, robin.murphy@arm.com
Cc:     Mark Rutland <mark.rutland@arm.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] perf/arm-cmn: Add shutdown routine
Message-ID: <20230119181444.GA20563@willie-the-truck>
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On Thu, Jan 19, 2023 at 11:10:29AM -0600, Geoff Blake wrote:
> On Thu, 19 Jan 2023, Robin Murphy wrote:
>  
> > If you have a convincing argument that returning IRQ_NONE for unexpected
> > spurious interrupts is a real and important concern, then please propose
> > a general solution, because if it matters for arm-cmn then it matters
> > for hundreds of other drivers too, by rough estimate:
> > 
> > $ git grep -l IRQ_NONE '*.c' | xargs git grep -L IRQF_SHARED | wc -l
> > 834
> 
> The general solution for IRQ_NONE exists in the layer above the 
> driver, it complains with a visible warning that something might be wrong 
> and then moves on. Nothing more is needed.
> 
> Your shutdown routine that flips DT_EN in CMN_DT_DTC_CTL is sufficient, as 
> after some testing it solves the problem with left over IRQs for my kexec 
> use case.  

Please can you two let me know when you've settled on a fix for this? I'm
not going to queue something that you don't both agree on, although it seems
like we're quibbling over details at this point so maybe let's get
_something_ in and then work to improve it later?

Cheers,

Will