Re: [PATCH bpf-next 1/3] mm/vmalloc: introduce vmalloc_exec which allocates RO+X memory

Uladzislau Rezki
2022-07-14T18:16:04Z

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