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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Tue, 7 Jan 2020 09:08:31 +0100
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Subject: Re: [PATCH v3 02/22] compat: provide compat_ptr() on all architectures
To:     Michael Ellerman <mpe@ellerman.id.au>
Cc:     "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
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On Tue, Jan 7, 2020 at 3:05 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
> Arnd Bergmann <arnd@arndb.de> writes:
> > +
> > +static inline compat_uptr_t ptr_to_compat(void __user *uptr)
> > +{
> > +     return (u32)(unsigned long)uptr;
> > +}
>
> Is there a reason we cast to u32 directly instead of using compat_uptr_t?

Probably Al found this to be more explicit at the time when he introduced
it on all the architectures in 2005. I just moved it here and kept the
definition.

       Arnd