[PATCH v3 04/10] mips: use fallback for random_get_entropy() instead of zero
Jason A. Donenfeld
Jason at zx2c4.com
Tue Apr 12 10:27:48 PDT 2022
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 at linutronix.de>
Cc: Arnd Bergmann <arnd at arndb.de>
Cc: Thomas Bogendoerfer <tsbogend at alpha.franken.de>
Signed-off-by: Jason A. Donenfeld <Jason at zx2c4.com>
---
arch/mips/include/asm/timex.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/mips/include/asm/timex.h b/arch/mips/include/asm/timex.h
index b05bb70a2e46..abc60a6395e3 100644
--- a/arch/mips/include/asm/timex.h
+++ b/arch/mips/include/asm/timex.h
@@ -94,7 +94,7 @@ static inline unsigned long random_get_entropy(void)
else if (likely(imp != PRID_IMP_R6000 && imp != PRID_IMP_R6000A))
return read_c0_random();
else
- return 0; /* no usable register */
+ return random_get_entropy_fallback(); /* no usable register */
}
#define random_get_entropy random_get_entropy
--
2.35.1
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