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Date:   Tue, 19 Apr 2022 11:14:01 +0200
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Subject: Re: [PATCH v1] thermal/core: change mm alloc method to avoid kernel
 warning
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To:     Zhang Rui <rui.zhang@intel.com>, Junwen Wu <wudaemon@163.com>,
        rafael@kernel.org, amitk@kernel.org
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 <a7861e9a6a311f09c03b2e6e47dd4d3283cb58e2.camel@intel.com>
From:   Daniel Lezcano <daniel.lezcano@linaro.org>
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On 19/04/2022 10:48, Zhang Rui wrote:
> On Sun, 2022-04-17 at 12:56 +0000, Junwen Wu wrote:
>> Very high cooling device max state value makes cooling device stats
>> buffer allocation fails,like below.Using kzvalloc instead of kzalloc
>> can avoid this issue.
> 
> When a cooling device has big max_state, this patch can get ride of the
> warning here, but still we end up with the read failure of the
> trans_table in sysfs because it is larger than PAGE_SIZE.
> 
> $ cat /sys/class/thermal/cooling_device8/stats/trans_table
> cat: /sys/class/thermal/cooling_device8/stats/trans_table: File too
> large
> 
> IMO, unless we can fix both places, I'd suggest we skip allocating and
> creating the broken trans_table attr. Like a prototype patch below

Why not create a thermal debugfs with real useful information and get 
rid of this broken code ?

I've some prototype code I can respin to RFC


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