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Subject: Re: [PATCH] iio: trigger: sysfs: Disable irqs before calling
 iio_trigger_poll()
To:     Jonathan Cameron <jic23@kernel.org>,
        Christian Eggers <ceggers@arri.de>
Cc:     stable@vger.kernel.org, Hartmut Knaack <knaack.h@gmx.de>,
        Peter Meerwald-Stadler <pmeerw@pmeerw.net>,
        linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20200727145714.4377-1-ceggers@arri.de>
 <20200801170234.2953b087@archlinux>
From:   Lars-Peter Clausen <lars@metafoo.de>
Message-ID: <28c6add2-311e-5638-e890-53a2248f560a@metafoo.de>
Date:   Sun, 2 Aug 2020 17:05:51 +0200
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On 8/1/20 6:02 PM, Jonathan Cameron wrote:
> On Mon, 27 Jul 2020 16:57:13 +0200
> Christian Eggers <ceggers@arri.de> wrote:
>
>> iio_trigger_poll() calls generic_handle_irq(). This function expects to
>> be run with local IRQs disabled.
> Was there an error or warning that lead to this patch?
> Or can you point to what call in generic_handle_irq is making the
> assumption that we are breaking?
>
> Given this is using the irq_work framework I'm wondering if this is
> a more general problem?
>
> Basically more info please!

There is this series https://lkml.org/lkml/2020/3/6/433 which causes 
generic_handle_irq() to issue an warning if it is called with IRQs on, 
for a IRQ controller that can't handle it.

But I'm not convinced this applies to the IIO code, since this is a 
purely virtual interrupt and is not interfering with any interrupt 
controller hardware.