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	Fri, 24 Nov 2023 17:22:57 +0200
Date: Fri, 24 Nov 2023 17:22:57 +0200
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: Lukas Wunner <lukas@wunner.de>, Heiner Kallweit <hkallweit1@gmail.com>,
	Keith Busch <kbusch@kernel.org>, Wolfram Sang <wsa@kernel.org>,
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	"linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>,
	Bjorn Helgaas <bhelgaas@google.com>
Subject: Re: [bug report] lockdep WARN at PCI device rescan
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Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo

On Fri, Nov 24, 2023 at 10:49:45AM +0000, Shinichiro Kawasaki wrote:
> On Nov 14, 2023 / 19:58, Andy Shevchenko wrote:

...

> I created a patch below and confirmed it avoided the lockdep WARN. The
> i2c-i801 probe was ok at system boot.

Another possible solution I was thinking about is to have a local cache,
so, make p2sb.c to be called just after PCI enumeration at boot time
to cache the P2SB device's bar, and then cache the bar based on the device
in question at the first call. Yet it may not remove all theoretical /
possible scenarios with dead lock (taking into account hotpluggable
devices), but won't fail the i801 driver in the above use case IIUC.

-- 
With Best Regards,
Andy Shevchenko