A safer kmalloc() for Linux 7.0

9 hours ago

kmalloc() is a general-purpose interface to the slab allocator for small memory chunks in the kernel.
The kmalloc() API has remained largely unchanged since its introduction in 1992, with minor type adjustments.
Common errors with kmalloc() include incorrect size allocation due to untyped return values and lack of size checks.
The 7.0 kernel introduces safer memory allocation functions like kmalloc_obj(), kmalloc_objs(), kzalloc_obj(), and kzalloc_objs().
New functions provide type safety, eliminate the need for sizeof(), and prevent common allocation mistakes.
kmalloc_flex() is introduced for structures with flexible array members to ensure correct sizing.
Large-scale patching converted much of the kernel code to use the new allocation functions.
Torvalds made the GFP_KERNEL argument optional in the new functions, defaulting to GFP_KERNEL when not specified.
The changes aim to reduce silly mistakes and improve code readability, though they may cause merge conflicts.

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