[PATCH 3/4] rndhw: avoid type-punching

Jussi Kivilinna jussi.kivilinna at iki.fi
Sat Jan 28 14:13:19 CET 2017

* random/rndhw.c (rdrand_long, rdrand_nlong): Add 'volatile' for
(poll_drng): Convert buffer to 'unsigned long[]' and make use of DIM

Signed-off-by: Jussi Kivilinna <jussi.kivilinna at iki.fi>
 0 files changed

diff --git a/random/rndhw.c b/random/rndhw.c
index 8e50751..7c75955 100644
--- a/random/rndhw.c
+++ b/random/rndhw.c
@@ -129,7 +129,7 @@ poll_padlock (void (*add)(const void*, size_t, enum random_origins),
 # endif
 static inline int
-rdrand_long (unsigned long *v)
+rdrand_long (volatile unsigned long *v)
   int ok;
   asm volatile ("1: " RDRAND_LONG "\n\t"
@@ -145,7 +145,7 @@ rdrand_long (unsigned long *v)
 static inline int
-rdrand_nlong (unsigned long *v, int count)
+rdrand_nlong (volatile unsigned long *v, int count)
   while (count--)
     if (!rdrand_long(v++))
@@ -157,12 +157,12 @@ rdrand_nlong (unsigned long *v, int count)
 static size_t
 poll_drng (add_fn_t add, enum random_origins origin, int fast)
-  volatile char buffer[64] __attribute__ ((aligned (8)));
+  volatile unsigned long buffer[8];
   unsigned int nbytes = sizeof (buffer);
-  if (!rdrand_nlong ((unsigned long *)buffer, sizeof(buffer)/sizeof(long)))
+  if (!rdrand_nlong (buffer, DIM(buffer)))
     return 0;
   (*add)((void *)buffer, nbytes, origin);
   return nbytes;

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