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Date:   Thu, 24 Nov 2022 12:57:30 +0100
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Florian Weimer <fweimer@redhat.com>
Cc:     linux-kernel@vger.kernel.org, patches@lists.linux.dev,
        tglx@linutronix.de, linux-crypto@vger.kernel.org, x86@kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>,
        Carlos O'Donell <carlos@redhat.com>
Subject: Re: [PATCH v6 2/3] random: introduce generic vDSO getrandom()
 implementation
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Hi Florian,

On Thu, Nov 24, 2022 at 06:28:44AM +0100, Florian Weimer wrote:
> > Right? And if you look at the expansion of that glibc macro, it's just:
> >
> >   #define INTERNAL_SYSCALL_ERROR_P(val) \
> >     ((unsigned long int) (val) > -4096UL)
> >
> > So it looks like the same exact thing?
> 
> syscall already does internally (with a translation to -1, not NULL), so
> the caller shouldn't do it again.  The userspace syscall function does
> *not* return an error code.

Ahh, okay. Thanks. I'll fix up the example to assume those semantics.

Jason