Unreliable Guide To Hacking The Linux Kernel
PrevChapter 6. Common Routines 

kmalloc()/kfree() include/linux/slab.h

[MAY SLEEP: SEE BELOW]

These routines are used to dynamically request pointer-aligned chunks of memory, like malloc and free do in userspace, but kmalloc() takes an extra flag word. Important values:

GFP_KERNEL
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