RE: [PATCH] thermal: sysfs: Fall back to vmalloc() for cooling device's statistics

[David Laight]

From: Yue Hu
> Sent: 21 August 2020 03:44
> 
> From: Yue Hu <huyue2@xxxxxxxxxx>
> 
> We observed warning about kzalloc() when register thermal cooling device
> in backlight_device_register(). backlight display can be a cooling device
> since reducing screen brightness will can help reduce temperature.
> 
> However, ->get_max_state of backlight will assign max brightness of 1024
> to states. The memory size can be getting 1MB+ due to states * states.
> That is so large to trigger kmalloc() warning.

I can't help feeling that there is an 'adequate' implementation
that doesn't require anywhere near 1MB of memory.

	David

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