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    SubjectRe: [PATCH v5 06/11] nios2: use fallback for random_get_entropy() instead of zero
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    On 4/19/22 06:16, Jason A. Donenfeld wrote:
    > In the event that random_get_entropy() can't access a cycle counter or
    > similar, falling back to returning 0 is really not the best we can do.
    > Instead, at least calling random_get_entropy_fallback() would be
    > preferable, because that always needs to return _something_, even
    > falling back to jiffies eventually. It's not as though
    > random_get_entropy_fallback() is super high precision or guaranteed to
    > be entropic, but basically anything that's not zero all the time is
    > better than returning zero all the time.
    >
    > Cc: Thomas Gleixner <tglx@linutronix.de>
    > Cc: Arnd Bergmann <arnd@arndb.de>
    > Cc: Dinh Nguyen <dinguyen@kernel.org>
    > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
    > ---
    > arch/nios2/include/asm/timex.h | 2 ++
    > 1 file changed, 2 insertions(+)
    >
    > diff --git a/arch/nios2/include/asm/timex.h b/arch/nios2/include/asm/timex.h
    > index a769f871b28d..d9a3f426cdda 100644
    > --- a/arch/nios2/include/asm/timex.h
    > +++ b/arch/nios2/include/asm/timex.h
    > @@ -9,4 +9,6 @@ typedef unsigned long cycles_t;
    >
    > extern cycles_t get_cycles(void);
    >
    > +#define random_get_entropy() (((unsigned long)get_cycles()) ?: random_get_entropy_fallback())
    > +
    > #endif

    Acked-by: Dinh Nguyen <dinguyen@kernel.org>

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