[PATCH v5 02/11] m68k: use fallback for random_get_entropy() instead of zero

Jason A. Donenfeld
2022-04-19T11:18:19Z

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>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
arch/m68k/include/asm/timex.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/m68k/include/asm/timex.h b/arch/m68k/include/asm/timex.h
index 6a21d9358280..f4a7a340f4ca 100644
--- a/arch/m68k/include/asm/timex.h
+++ b/arch/m68k/include/asm/timex.h
@@ -35,7 +35,7 @@ static inline unsigned long random_get_entropy(void)
{
if (mach_random_get_entropy)
return mach_random_get_entropy();
- return 0;
+ return random_get_entropy_fallback();
}
#define random_get_entropy random_get_entropy

--
2.35.1