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Date: Tue, 18 Nov 2025 10:44:25 +0000
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Subject: Re: [PATCH v5 10/34] arm_mpam: Add probe/remove for mpam msc driver
 and kbuild boiler plate
To: Markus Elfring <Markus.Elfring@web.de>, James Morse
 <james.morse@arm.com>, linux-arm-kernel@lists.infradead.org,
 linux-acpi@vger.kernel.org
Cc: LKML <linux-kernel@vger.kernel.org>,
 Amit Singh Tomar <amitsinght@marvell.com>,
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 Baolin Wang <baolin.wang@linux.alibaba.com>,
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 <rafael@kernel.org>, Rob Herring <robh@kernel.org>,
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 Shanker Donthineni <sdonthineni@nvidia.com>,
 Shaopeng Tan <tan.shaopeng@fujitsu.com>, Sudeep Holla
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References: <20251117170014.4113754-11-ben.horgan@arm.com>
 <a5306f5a-92b0-437d-b384-40863fbed6d8@web.de>
From: Ben Horgan <ben.horgan@arm.com>
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Hi Markus,

On 11/17/25 19:50, Markus Elfring wrote:
> …
>> +++ b/drivers/resctrl/mpam_devices.c
>> @@ -0,0 +1,190 @@
> …
>> +static int mpam_msc_drv_probe(struct platform_device *pdev)
>> +{
> …
>> +	mutex_lock(&mpam_list_lock);
>> +	msc = do_mpam_msc_drv_probe(pdev);
>> +	mutex_unlock(&mpam_list_lock);
> …
> 
> Does anything hinder you to integrate statements like “guard(mutex)(&mpam_list_lock);” here?
> https://elixir.bootlin.com/linux/v6.18-rc6/source/include/linux/mutex.h#L228

The mpam_list_lock needs to be dropped before the end of the scope as it
is also taken in mpam_msc_drv_remove().

> 
> Regards,
> Markus

Thanks,

Ben