... from <linux/compiler.h>.
<linux/wordpart.h> is the header defining them on Linux 6.12 (I didn't check older versions). <linux/wordpart.h> is also included from <linux/kernel.h>.
The DRM generic code started to depend on <linux/wordpart.h> in Linux 6.12.
This is part of the update of DRM drivers to Linux 6.12.
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