Re: [PATCH v2 1/4] KVM: s390: Replace get_zeroed_page() with kzalloc() for the STHYI buffer

[sashiko-bot@kernel.org]

> handle_sthyi() allocates the buffer that receives the STHYI response
> block before it is copied to the guest.
> 
> This buffer can be allocated with kmalloc() as there's nothing special
> about it to go directly to the page allocator.
> 
> kmalloc() provides a better API that does not require ugly casts and
> kfree() does not need to know the size of the freed object.
> 
> Performance difference between kmalloc() and __get_free_pages() is not
> measurable as both allocators take an object/page from a per-CPU list for
> fast path allocations.
> 
> For the slow path the performance is anyway determined by the amount of
> reclaim involved rather than by what allocator is used.
> 
> The only goto in that function does not unwind anything, it merely skips
> to the exit when the function code is invalid. Turn it into an early
> return so that the buffer can be freed with __free(kfree).
> 
> Replace use of get_zeroed_page() with kzalloc() and free_page() with
> kfree().
> 
> Assisted-by: copilot:claude-opus
> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260906-s390-kvm-v2-0-2cf6434e6646@kernel.org?part=1