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From:   Uladzislau Rezki <urezki@gmail.com>
Date:   Thu, 14 Jul 2022 20:15:56 +0200
To:     Song Liu <songliubraving@fb.com>
Cc:     Christoph Hellwig <hch@infradead.org>, Song Liu <song@kernel.org>,
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Subject: Re: [PATCH bpf-next 1/3] mm/vmalloc: introduce vmalloc_exec which
 allocates RO+X memory
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On Thu, Jul 14, 2022 at 04:54:40AM +0000, Song Liu wrote:
> 
> 
> > On Jul 13, 2022, at 9:23 PM, Christoph Hellwig <hch@infradead.org> wrote:
> > 
> > On Wed, Jul 13, 2022 at 03:49:45PM +0000, Song Liu wrote:
> >> 
> >> 
> >>> On Jul 13, 2022, at 3:08 AM, Christoph Hellwig <hch@infradead.org> wrote:
> >>> 
> >>> NAK.  This is not something that should be an exported public API
> >>> ever.
> >> 
> >> Hmm.. I will remove EXPORT_SYMBOL_GPL (if we ever do a v2 of this..)
> > 
> > Even without that it really is not a vmalloc API anyway.  
> 
> This ...
> 
> > Executable
> > memory needs to be written first, so we should allocate it in that state
> > and only mark it executable after that write has completed.
> 
> ... and this are two separate NAKs.
> 
> For the first NAK, I agree that my version is another layer on top of 
> vmalloc. But what do you think about Peter's idea? AFAICT, that fits
> well in vmalloc logic. 
> 
I am not able to find the patch/change to see what you have done. But
please do not build a new allocator on top of vmalloc code. We have
three different ones what make things to be complicated :)

--
Uladzislau Rezki