Re: [RESEND PATCH 2/4] x86: add phys addr validity check for /dev/mem mmap

From: Frantisek Hrbata
Date: Tue Sep 30 2014 - 08:41:50 EST

On Mon, Sep 29, 2014 at 10:15:28PM +0200, Thomas Gleixner wrote:
> On Mon, 29 Sep 2014, Frantisek Hrbata wrote:
> > V2: fix pfn check in valid_mmap_phys_addr_range, thanks to Dave Hansen
> AFAICT, Dave also asked you to change size_t count into something more
> intuitive, i.e. nr_bytes or such.


mea culpa, I for unknown reason changed it from "size" to "count". I guess some
cut&paste mess. The correct prototype used elsewhere in kernel is

int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)

Does it make sense to replace "count" with "size" so it's consistent with the
rest or do you prefer "nr_bytes" or as Dave proposed "len_bytes"?

I will fix this and I'm sorry Dave I did not change it as discussed. It totally
slipped my mind.

Many thanks Thomas.

> > +int valid_mmap_phys_addr_range(unsigned long pfn, size_t count)
> And right he is. I really had to look twice to see that count is
> actually number of bytes and not number of pages, which is what you
> expect after pfn.
> > +{
> > + return arch_pfn_possible(pfn + (count >> PAGE_SHIFT));
> > +}
> Thanks,
> tglx

Frantisek Hrbata
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