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Subject: Re: Access to non-RAM pages
From:   Benjamin Herrenschmidt <benh@kernel.crashing.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
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Date:   Mon, 03 Sep 2018 12:00:53 +1000
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On Sun, 2018-09-02 at 18:42 -0700, Linus Torvalds wrote:
> On Sun, Sep 2, 2018 at 6:38 PM Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> > It's not used for vmalloc stuff. It's just regular kmalloc().
> 
> Just to clarify .. that's true of the dcache stuff.
> 
> The strscpy case actually explicitly limits things to page boundaries
> and falls back to the byte-by-byte case after that.

Ah ok, that makes sense.

Still, I can potentially see an issue with DEBUG_PAGEALLOC

Cheers,
Ben.