linux-kernel - Re: [PATCH v3 03/13] mm/execmem, arch: convert simple overrides of module

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Message-ID: <00277a3acb36d2309156264c7e8484071bc91614.camel@intel.com>
Date:   Wed, 4 Oct 2023 15:39:26 +0000
From:   "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
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Subject: Re: [PATCH v3 03/13] mm/execmem, arch: convert simple overrides of
 module_alloc to execmem

On Tue, 2023-10-03 at 17:29 -0700, Rick Edgecombe wrote:
> It seems a bit weird to copy all of this. Is it trying to be faster
> or
> something?
> 
> Couldn't it just check r->start in execmem_text/data_alloc() path and
> switch to EXECMEM_DEFAULT if needed then? The execmem_range_is_data()
> part that comes later could be added to the logic there too. So this
> seems like unnecessary complexity to me or I don't see the reason.

I guess this is a bad idea because if you have the full size array
sitting around anyway you might as well use it and reduce the
exec_mem_alloc() logic. Just looking at it from the x86 side (and
similar) though, where there is actually only one execmem_range and it
building this whole array with identical data and it seems weird.