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 sched_clock() would be preferable, because
that always needs to return _something_, even falling back to jiffies
eventually. It's not as though sched_clock() 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: Arnd Bergmann <a...@arndb.de>
Cc: Thomas Bogendoerfer <tsbog...@alpha.franken.de>
Signed-off-by: Jason A. Donenfeld <ja...@zx2c4.com>
---
arch/mips/include/asm/timex.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/mips/include/asm/timex.h b/arch/mips/include/asm/timex.h
index b05bb70a2e46..1de8ded08bb7 100644
--- a/arch/mips/include/asm/timex.h
+++ b/arch/mips/include/asm/timex.h
@@ -12,6 +12,7 @@
#ifdef __KERNEL__
#include <linux/compiler.h>
+#include <linux/sched/clock.h>
#include <asm/cpu.h>
#include <asm/cpu-features.h>
@@ -94,7 +95,7 @@ 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 sched_clock(); /* no usable register */
}
#define random_get_entropy random_get_entropy
--
2.35.1
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