Re: [RFC] mm: Change the data type of huge page size from unsigned long to u64

[Rui Teng]

On 9/13/16 7:40 PM, Kirill A. Shutemov wrote:
> On Tue, Sep 13, 2016 at 07:21:07PM +0800, Rui Teng wrote:
> > On 9/13/16 5:32 PM, Kirill A. Shutemov wrote:
> > > On Tue, Sep 13, 2016 at 05:26:05PM +0800, Rui Teng wrote:
> > > > The huge page size could be 16G(0x400000000) on ppc64 architecture, and it will
> > > > cause an overflow on unsigned long data type(0xFFFFFFFF).
> > >
> > > Huh? ppc64 is 64-bit system and sizeof(void *) is equal to
> > > sizeof(unsigned long) on Linux (LP64 model).
> > >
> > > So where your 0xFFFFFFFF comes from?
> > The size of unsigned long data type is 4 bytes
>
> No, it's not.
Sorry, my fault!
I print the unsigned long with "%ul" instead of "%lu" and got the wrong
result. Sorry!