Re: [PATCH v3] EFI/runtime: switch to xv[mz]alloc_array()

[Jan Beulich <jbeulich@suse.com>]

On 12.08.2025 02:19, Daniel P. Smith wrote:
> On 7/23/25 09:39, Jan Beulich wrote:
>> Use the more "modern" form, thus doing away with effectively open-coding
>> xmalloc_array() at the same time. While there is a difference in
>> generated code, as xmalloc_bytes() forces SMP_CACHE_BYTES alignment, if
>> code really cared about such higher than default alignment, it should
>> request so explicitly.
> 
> While I don't object to the change itself, I think this description is a 
> bit over simplification of the change. If the allocation is under 
> PAGE_SIZE, then they are equivalent, but if it is over the page size 
> there are a few more differences than just cache alignment. It 
> completely changes the underlying allocator. I personally also find it a 
> bit of a stretch to call xmalloc_bytes(size) an open coded version of 
> xmalloc_array(char, size).

My take is that xmalloc_bytes() should never have existed. Hence why I
didn't add xzmalloc_bytes() when introducing that family of interfaces.

> With a stronger description of the change,

So what exactly do you mean by "stronger"? I can add that in the unlikely
event that one of the allocations is (near) PAGE_SIZE or larger, we now
wouldn't require contiguous memory anymore. Yet based on your comment at
the top I'm not quite sure if that's what you're after and/or enough to
satisfy your request.

> Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>

Thanks, but will need clarification first as per above.

Jan