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path: root/target/linux/generic/patches-3.3/050-rng_git_backport.patch
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--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -125,21 +125,26 @@
  * The current exported interfaces for gathering environmental noise
  * from the devices are:
  *
+ *	void add_device_randomness(const void *buf, unsigned int size);
  * 	void add_input_randomness(unsigned int type, unsigned int code,
  *                                unsigned int value);
- * 	void add_interrupt_randomness(int irq);
+ *	void add_interrupt_randomness(int irq, int irq_flags);
  * 	void add_disk_randomness(struct gendisk *disk);
  *
  * add_input_randomness() uses the input layer interrupt timing, as well as
  * the event type information from the hardware.
  *
- * add_interrupt_randomness() uses the inter-interrupt timing as random
- * inputs to the entropy pool.  Note that not all interrupts are good
- * sources of randomness!  For example, the timer interrupts is not a
- * good choice, because the periodicity of the interrupts is too
- * regular, and hence predictable to an attacker.  Network Interface
- * Controller interrupts are a better measure, since the timing of the
- * NIC interrupts are more unpredictable.
+ * add_interrupt_randomness() uses the interrupt timing as random
+ * inputs to the entropy pool. Using the cycle counters and the irq source
+ * as inputs, it feeds the randomness roughly once a second.
+ *
+ * add_device_randomness() is for adding data to the random pool that
+ * is likely to differ between two devices (or possibly even per boot).
+ * This would be things like MAC addresses or serial numbers, or the
+ * read-out of the RTC. This does *not* add any actual entropy to the
+ * pool, but it initializes the pool to different values for devices
+ * that might otherwise be identical and have very little entropy
+ * available to them (particularly common in the embedded world).
  *
  * add_disk_randomness() uses what amounts to the seek time of block
  * layer request events, on a per-disk_devt basis, as input to the
@@ -248,6 +253,7 @@
 #include <linux/percpu.h>
 #include <linux/cryptohash.h>
 #include <linux/fips.h>
+#include <linux/ptrace.h>
 
 #ifdef CONFIG_GENERIC_HARDIRQS
 # include <linux/irq.h>
@@ -256,8 +262,12 @@
 #include <asm/processor.h>
 #include <asm/uaccess.h>
 #include <asm/irq.h>
+#include <asm/irq_regs.h>
 #include <asm/io.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/random.h>
+
 /*
  * Configuration information
  */
@@ -420,8 +430,10 @@ struct entropy_store {
 	/* read-write data: */
 	spinlock_t lock;
 	unsigned add_ptr;
+	unsigned input_rotate;
 	int entropy_count;
-	int input_rotate;
+	int entropy_total;
+	unsigned int initialized:1;
 	__u8 last_data[EXTRACT_SIZE];
 };
 
@@ -454,6 +466,10 @@ static struct entropy_store nonblocking_
 	.pool = nonblocking_pool_data
 };
 
+static __u32 const twist_table[8] = {
+	0x00000000, 0x3b6e20c8, 0x76dc4190, 0x4db26158,
+	0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278 };
+
 /*
  * This function adds bytes into the entropy "pool".  It does not
  * update the entropy estimate.  The caller should call
@@ -464,29 +480,24 @@ static struct entropy_store nonblocking_
  * it's cheap to do so and helps slightly in the expected case where
  * the entropy is concentrated in the low-order bits.
  */
-static void mix_pool_bytes_extract(struct entropy_store *r, const void *in,
-				   int nbytes, __u8 out[64])
+static void _mix_pool_bytes(struct entropy_store *r, const void *in,
+			    int nbytes, __u8 out[64])
 {
-	static __u32 const twist_table[8] = {
-		0x00000000, 0x3b6e20c8, 0x76dc4190, 0x4db26158,
-		0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278 };
 	unsigned long i, j, tap1, tap2, tap3, tap4, tap5;
 	int input_rotate;
 	int wordmask = r->poolinfo->poolwords - 1;
 	const char *bytes = in;
 	__u32 w;
-	unsigned long flags;
 
-	/* Taps are constant, so we can load them without holding r->lock.  */
 	tap1 = r->poolinfo->tap1;
 	tap2 = r->poolinfo->tap2;
 	tap3 = r->poolinfo->tap3;
 	tap4 = r->poolinfo->tap4;
 	tap5 = r->poolinfo->tap5;
 
-	spin_lock_irqsave(&r->lock, flags);
-	input_rotate = r->input_rotate;
-	i = r->add_ptr;
+	smp_rmb();
+	input_rotate = ACCESS_ONCE(r->input_rotate);
+	i = ACCESS_ONCE(r->add_ptr);
 
 	/* mix one byte at a time to simplify size handling and churn faster */
 	while (nbytes--) {
@@ -513,19 +524,61 @@ static void mix_pool_bytes_extract(struc
 		input_rotate += i ? 7 : 14;
 	}
 
-	r->input_rotate = input_rotate;
-	r->add_ptr = i;
+	ACCESS_ONCE(r->input_rotate) = input_rotate;
+	ACCESS_ONCE(r->add_ptr) = i;
+	smp_wmb();
 
 	if (out)
 		for (j = 0; j < 16; j++)
 			((__u32 *)out)[j] = r->pool[(i - j) & wordmask];
+}
+
+static void __mix_pool_bytes(struct entropy_store *r, const void *in,
+			     int nbytes, __u8 out[64])
+{
+	trace_mix_pool_bytes_nolock(r->name, nbytes, _RET_IP_);
+	_mix_pool_bytes(r, in, nbytes, out);
+}
 
+static void mix_pool_bytes(struct entropy_store *r, const void *in,
+			   int nbytes, __u8 out[64])
+{
+	unsigned long flags;
+
+	trace_mix_pool_bytes(r->name, nbytes, _RET_IP_);
+	spin_lock_irqsave(&r->lock, flags);
+	_mix_pool_bytes(r, in, nbytes, out);
 	spin_unlock_irqrestore(&r->lock, flags);
 }
 
-static void mix_pool_bytes(struct entropy_store *r, const void *in, int bytes)
+struct fast_pool {
+	__u32		pool[4];
+	unsigned long	last;
+	unsigned short	count;
+	unsigned char	rotate;
+	unsigned char	last_timer_intr;
+};
+
+/*
+ * This is a fast mixing routine used by the interrupt randomness
+ * collector.  It's hardcoded for an 128 bit pool and assumes that any
+ * locks that might be needed are taken by the caller.
+ */
+static void fast_mix(struct fast_pool *f, const void *in, int nbytes)
 {
-       mix_pool_bytes_extract(r, in, bytes, NULL);
+	const char	*bytes = in;
+	__u32		w;
+	unsigned	i = f->count;
+	unsigned	input_rotate = f->rotate;
+
+	while (nbytes--) {
+		w = rol32(*bytes++, input_rotate & 31) ^ f->pool[i & 3] ^
+			f->pool[(i + 1) & 3];
+		f->pool[i & 3] = (w >> 3) ^ twist_table[w & 7];
+		input_rotate += (i++ & 3) ? 7 : 14;
+	}
+	f->count = i;
+	f->rotate = input_rotate;
 }
 
 /*
@@ -533,30 +586,38 @@ static void mix_pool_bytes(struct entrop
  */
 static void credit_entropy_bits(struct entropy_store *r, int nbits)
 {
-	unsigned long flags;
-	int entropy_count;
+	int entropy_count, orig;
 
 	if (!nbits)
 		return;
 
-	spin_lock_irqsave(&r->lock, flags);
-
 	DEBUG_ENT("added %d entropy credits to %s\n", nbits, r->name);
-	entropy_count = r->entropy_count;
+retry:
+	entropy_count = orig = ACCESS_ONCE(r->entropy_count);
 	entropy_count += nbits;
+
 	if (entropy_count < 0) {
 		DEBUG_ENT("negative entropy/overflow\n");
 		entropy_count = 0;
 	} else if (entropy_count > r->poolinfo->POOLBITS)
 		entropy_count = r->poolinfo->POOLBITS;
-	r->entropy_count = entropy_count;
+	if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig)
+		goto retry;
+
+	if (!r->initialized && nbits > 0) {
+		r->entropy_total += nbits;
+		if (r->entropy_total > 128)
+			r->initialized = 1;
+	}
+
+	trace_credit_entropy_bits(r->name, nbits, entropy_count,
+				  r->entropy_total, _RET_IP_);
 
 	/* should we wake readers? */
 	if (r == &input_pool && entropy_count >= random_read_wakeup_thresh) {
 		wake_up_interruptible(&random_read_wait);
 		kill_fasync(&fasync, SIGIO, POLL_IN);
 	}
-	spin_unlock_irqrestore(&r->lock, flags);
 }
 
 /*********************************************************************
@@ -609,6 +670,25 @@ static void set_timer_rand_state(unsigne
 }
 #endif
 
+/*
+ * Add device- or boot-specific data to the input and nonblocking
+ * pools to help initialize them to unique values.
+ *
+ * None of this adds any entropy, it is meant to avoid the
+ * problem of the nonblocking pool having similar initial state
+ * across largely identical devices.
+ */
+void add_device_randomness(const void *buf, unsigned int size)
+{
+	unsigned long time = get_cycles() ^ jiffies;
+
+	mix_pool_bytes(&input_pool, buf, size, NULL);
+	mix_pool_bytes(&input_pool, &time, sizeof(time), NULL);
+	mix_pool_bytes(&nonblocking_pool, buf, size, NULL);
+	mix_pool_bytes(&nonblocking_pool, &time, sizeof(time), NULL);
+}
+EXPORT_SYMBOL(add_device_randomness);
+
 static struct timer_rand_state input_timer_state;
 
 /*
@@ -637,13 +717,9 @@ static void add_timer_randomness(struct
 		goto out;
 
 	sample.jiffies = jiffies;
-
-	/* Use arch random value, fall back to cycles */
-	if (!arch_get_random_int(&sample.cycles))
-		sample.cycles = get_cycles();
-
+	sample.cycles = get_cycles();
 	sample.num = num;
-	mix_pool_bytes(&input_pool, &sample, sizeof(sample));
+	mix_pool_bytes(&input_pool, &sample, sizeof(sample), NULL);
 
 	/*
 	 * Calculate number of bits of randomness we probably added.
@@ -700,17 +776,48 @@ void add_input_randomness(unsigned int t
 }
 EXPORT_SYMBOL_GPL(add_input_randomness);
 
-void add_interrupt_randomness(int irq)
+static DEFINE_PER_CPU(struct fast_pool, irq_randomness);
+
+void add_interrupt_randomness(int irq, int irq_flags)
 {
-	struct timer_rand_state *state;
+	struct entropy_store	*r;
+	struct fast_pool	*fast_pool = &__get_cpu_var(irq_randomness);
+	struct pt_regs		*regs = get_irq_regs();
+	unsigned long		now = jiffies;
+	__u32			input[4], cycles = get_cycles();
+
+	input[0] = cycles ^ jiffies;
+	input[1] = irq;
+	if (regs) {
+		__u64 ip = instruction_pointer(regs);
+		input[2] = ip;
+		input[3] = ip >> 32;
+	}
 
-	state = get_timer_rand_state(irq);
+	fast_mix(fast_pool, input, sizeof(input));
 
-	if (state == NULL)
+	if ((fast_pool->count & 1023) &&
+	    !time_after(now, fast_pool->last + HZ))
 		return;
 
-	DEBUG_ENT("irq event %d\n", irq);
-	add_timer_randomness(state, 0x100 + irq);
+	fast_pool->last = now;
+
+	r = nonblocking_pool.initialized ? &input_pool : &nonblocking_pool;
+	__mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool), NULL);
+	/*
+	 * If we don't have a valid cycle counter, and we see
+	 * back-to-back timer interrupts, then skip giving credit for
+	 * any entropy.
+	 */
+	if (cycles == 0) {
+		if (irq_flags & __IRQF_TIMER) {
+			if (fast_pool->last_timer_intr)
+				return;
+			fast_pool->last_timer_intr = 1;
+		} else
+			fast_pool->last_timer_intr = 0;
+	}
+	credit_entropy_bits(r, 1);
 }
 
 #ifdef CONFIG_BLOCK
@@ -742,7 +849,11 @@ static ssize_t extract_entropy(struct en
  */
 static void xfer_secondary_pool(struct entropy_store *r, size_t nbytes)
 {
-	__u32 tmp[OUTPUT_POOL_WORDS];
+	union {
+		__u32	tmp[OUTPUT_POOL_WORDS];
+		long	hwrand[4];
+	} u;
+	int	i;
 
 	if (r->pull && r->entropy_count < nbytes * 8 &&
 	    r->entropy_count < r->poolinfo->POOLBITS) {
@@ -753,17 +864,22 @@ static void xfer_secondary_pool(struct e
 		/* pull at least as many as BYTES as wakeup BITS */
 		bytes = max_t(int, bytes, random_read_wakeup_thresh / 8);
 		/* but never more than the buffer size */
-		bytes = min_t(int, bytes, sizeof(tmp));
+		bytes = min_t(int, bytes, sizeof(u.tmp));
 
 		DEBUG_ENT("going to reseed %s with %d bits "
 			  "(%d of %d requested)\n",
 			  r->name, bytes * 8, nbytes * 8, r->entropy_count);
 
-		bytes = extract_entropy(r->pull, tmp, bytes,
+		bytes = extract_entropy(r->pull, u.tmp, bytes,
 					random_read_wakeup_thresh / 8, rsvd);
-		mix_pool_bytes(r, tmp, bytes);
+		mix_pool_bytes(r, u.tmp, bytes, NULL);
 		credit_entropy_bits(r, bytes*8);
 	}
+	for (i = 0; i < 4; i++)
+		if (arch_get_random_long(&u.hwrand[i]))
+			break;
+	if (i)
+		mix_pool_bytes(r, &u.hwrand, i * sizeof(u.hwrand[0]), 0);
 }
 
 /*
@@ -822,9 +938,11 @@ static void extract_buf(struct entropy_s
 	int i;
 	__u32 hash[5], workspace[SHA_WORKSPACE_WORDS];
 	__u8 extract[64];
+	unsigned long flags;
 
 	/* Generate a hash across the pool, 16 words (512 bits) at a time */
 	sha_init(hash);
+	spin_lock_irqsave(&r->lock, flags);
 	for (i = 0; i < r->poolinfo->poolwords; i += 16)
 		sha_transform(hash, (__u8 *)(r->pool + i), workspace);
 
@@ -837,7 +955,8 @@ static void extract_buf(struct entropy_s
 	 * brute-forcing the feedback as hard as brute-forcing the
 	 * hash.
 	 */
-	mix_pool_bytes_extract(r, hash, sizeof(hash), extract);
+	__mix_pool_bytes(r, hash, sizeof(hash), extract);
+	spin_unlock_irqrestore(&r->lock, flags);
 
 	/*
 	 * To avoid duplicates, we atomically extract a portion of the
@@ -860,12 +979,12 @@ static void extract_buf(struct entropy_s
 }
 
 static ssize_t extract_entropy(struct entropy_store *r, void *buf,
-			       size_t nbytes, int min, int reserved)
+				 size_t nbytes, int min, int reserved)
 {
 	ssize_t ret = 0, i;
 	__u8 tmp[EXTRACT_SIZE];
-	unsigned long flags;
 
+	trace_extract_entropy(r->name, nbytes, r->entropy_count, _RET_IP_);
 	xfer_secondary_pool(r, nbytes);
 	nbytes = account(r, nbytes, min, reserved);
 
@@ -873,6 +992,8 @@ static ssize_t extract_entropy(struct en
 		extract_buf(r, tmp);
 
 		if (fips_enabled) {
+			unsigned long flags;
+
 			spin_lock_irqsave(&r->lock, flags);
 			if (!memcmp(tmp, r->last_data, EXTRACT_SIZE))
 				panic("Hardware RNG duplicated output!\n");
@@ -898,6 +1019,7 @@ static ssize_t extract_entropy_user(stru
 	ssize_t ret = 0, i;
 	__u8 tmp[EXTRACT_SIZE];
 
+	trace_extract_entropy_user(r->name, nbytes, r->entropy_count, _RET_IP_);
 	xfer_secondary_pool(r, nbytes);
 	nbytes = account(r, nbytes, 0, 0);
 
@@ -931,17 +1053,35 @@ static ssize_t extract_entropy_user(stru
 
 /*
  * This function is the exported kernel interface.  It returns some
- * number of good random numbers, suitable for seeding TCP sequence
- * numbers, etc.
+ * number of good random numbers, suitable for key generation, seeding
+ * TCP sequence numbers, etc.  It does not use the hw random number
+ * generator, if available; use get_random_bytes_arch() for that.
  */
 void get_random_bytes(void *buf, int nbytes)
 {
+	extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0);
+}
+EXPORT_SYMBOL(get_random_bytes);
+
+/*
+ * This function will use the architecture-specific hardware random
+ * number generator if it is available.  The arch-specific hw RNG will
+ * almost certainly be faster than what we can do in software, but it
+ * is impossible to verify that it is implemented securely (as
+ * opposed, to, say, the AES encryption of a sequence number using a
+ * key known by the NSA).  So it's useful if we need the speed, but
+ * only if we're willing to trust the hardware manufacturer not to
+ * have put in a back door.
+ */
+void get_random_bytes_arch(void *buf, int nbytes)
+{
 	char *p = buf;
 
+	trace_get_random_bytes(nbytes, _RET_IP_);
 	while (nbytes) {
 		unsigned long v;
 		int chunk = min(nbytes, (int)sizeof(unsigned long));
-		
+
 		if (!arch_get_random_long(&v))
 			break;
 		
@@ -950,9 +1090,11 @@ void get_random_bytes(void *buf, int nby
 		nbytes -= chunk;
 	}
 
-	extract_entropy(&nonblocking_pool, p, nbytes, 0, 0);
+	if (nbytes)
+		extract_entropy(&nonblocking_pool, p, nbytes, 0, 0);
 }
-EXPORT_SYMBOL(get_random_bytes);
+EXPORT_SYMBOL(get_random_bytes_arch);
+
 
 /*
  * init_std_data - initialize pool with system data
@@ -966,21 +1108,18 @@ EXPORT_SYMBOL(get_random_bytes);
 static void init_std_data(struct entropy_store *r)
 {
 	int i;
-	ktime_t now;
-	unsigned long flags;
+	ktime_t now = ktime_get_real();
+	unsigned long rv;
 
-	spin_lock_irqsave(&r->lock, flags);
 	r->entropy_count = 0;
-	spin_unlock_irqrestore(&r->lock, flags);
-
-	now = ktime_get_real();
-	mix_pool_bytes(r, &now, sizeof(now));
-	for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof flags) {
-		if (!arch_get_random_long(&flags))
+	r->entropy_total = 0;
+	mix_pool_bytes(r, &now, sizeof(now), NULL);
+	for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof(rv)) {
+		if (!arch_get_random_long(&rv))
 			break;
-		mix_pool_bytes(r, &flags, sizeof(flags));
+		mix_pool_bytes(r, &rv, sizeof(rv), NULL);
 	}
-	mix_pool_bytes(r, utsname(), sizeof(*(utsname())));
+	mix_pool_bytes(r, utsname(), sizeof(*(utsname())), NULL);
 }
 
 static int rand_initialize(void)
@@ -1117,7 +1256,7 @@ write_pool(struct entropy_store *r, cons
 		count -= bytes;
 		p += bytes;
 
-		mix_pool_bytes(r, buf, bytes);
+		mix_pool_bytes(r, buf, bytes, NULL);
 		cond_resched();
 	}
 
@@ -1274,6 +1413,7 @@ static int proc_do_uuid(ctl_table *table
 }
 
 static int sysctl_poolsize = INPUT_POOL_WORDS * 32;
+extern ctl_table random_table[];
 ctl_table random_table[] = {
 	{
 		.procname	= "poolsize",
@@ -1339,7 +1479,7 @@ late_initcall(random_int_secret_init);
  * value is not cryptographically secure but for several uses the cost of
  * depleting entropy is too high
  */
-DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash);
+static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash);
 unsigned int get_random_int(void)
 {
 	__u32 *hash;
--- a/drivers/mfd/ab3100-core.c
+++ b/drivers/mfd/ab3100-core.c
@@ -409,8 +409,6 @@ static irqreturn_t ab3100_irq_handler(in
 	u32 fatevent;
 	int err;
 
-	add_interrupt_randomness(irq);
-
 	err = ab3100_get_register_page_interruptible(ab3100, AB3100_EVENTA1,
 				       event_regs, 3);
 	if (err)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -24,6 +24,7 @@
 #include <linux/kthread.h>
 #include <linux/mutex.h>
 #include <linux/freezer.h>
+#include <linux/random.h>
 
 #include <asm/uaccess.h>
 #include <asm/byteorder.h>
@@ -1896,6 +1897,14 @@ int usb_new_device(struct usb_device *ud
 	/* Tell the world! */
 	announce_device(udev);
 
+	if (udev->serial)
+		add_device_randomness(udev->serial, strlen(udev->serial));
+	if (udev->product)
+		add_device_randomness(udev->product, strlen(udev->product));
+	if (udev->manufacturer)
+		add_device_randomness(udev->manufacturer,
+				      strlen(udev->manufacturer));
+
 	device_enable_async_suspend(&udev->dev);
 	/* Register the device.  The device driver is responsible
 	 * for configuring the device and invoking the add-device
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -50,11 +50,13 @@ struct rnd_state {
 
 extern void rand_initialize_irq(int irq);
 
+extern void add_device_randomness(const void *, unsigned int);
 extern void add_input_randomness(unsigned int type, unsigned int code,
 				 unsigned int value);
-extern void add_interrupt_randomness(int irq);
+extern void add_interrupt_randomness(int irq, int irq_flags);
 
 extern void get_random_bytes(void *buf, int nbytes);
+extern void get_random_bytes_arch(void *buf, int nbytes);
 void generate_random_uuid(unsigned char uuid_out[16]);
 
 #ifndef MODULE
--- /dev/null
+++ b/include/trace/events/random.h
@@ -0,0 +1,134 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM random
+
+#if !defined(_TRACE_RANDOM_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_RANDOM_H
+
+#include <linux/writeback.h>
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(random__mix_pool_bytes,
+	TP_PROTO(const char *pool_name, int bytes, unsigned long IP),
+
+	TP_ARGS(pool_name, bytes, IP),
+
+	TP_STRUCT__entry(
+		__field( const char *,	pool_name		)
+		__field(	  int,	bytes			)
+		__field(unsigned long,	IP			)
+	),
+
+	TP_fast_assign(
+		__entry->pool_name	= pool_name;
+		__entry->bytes		= bytes;
+		__entry->IP		= IP;
+	),
+
+	TP_printk("%s pool: bytes %d caller %pF",
+		  __entry->pool_name, __entry->bytes, (void *)__entry->IP)
+);
+
+DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes,
+	TP_PROTO(const char *pool_name, int bytes, unsigned long IP),
+
+	TP_ARGS(pool_name, bytes, IP)
+);
+
+DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes_nolock,
+	TP_PROTO(const char *pool_name, int bytes, unsigned long IP),
+
+	TP_ARGS(pool_name, bytes, IP)
+);
+
+TRACE_EVENT(credit_entropy_bits,
+	TP_PROTO(const char *pool_name, int bits, int entropy_count,
+		 int entropy_total, unsigned long IP),
+
+	TP_ARGS(pool_name, bits, entropy_count, entropy_total, IP),
+
+	TP_STRUCT__entry(
+		__field( const char *,	pool_name		)
+		__field(	  int,	bits			)
+		__field(	  int,	entropy_count		)
+		__field(	  int,	entropy_total		)
+		__field(unsigned long,	IP			)
+	),
+
+	TP_fast_assign(
+		__entry->pool_name	= pool_name;
+		__entry->bits		= bits;
+		__entry->entropy_count	= entropy_count;
+		__entry->entropy_total	= entropy_total;
+		__entry->IP		= IP;
+	),
+
+	TP_printk("%s pool: bits %d entropy_count %d entropy_total %d "
+		  "caller %pF", __entry->pool_name, __entry->bits,
+		  __entry->entropy_count, __entry->entropy_total,
+		  (void *)__entry->IP)
+);
+
+TRACE_EVENT(get_random_bytes,
+	TP_PROTO(int nbytes, unsigned long IP),
+
+	TP_ARGS(nbytes, IP),
+
+	TP_STRUCT__entry(
+		__field(	  int,	nbytes			)
+		__field(unsigned long,	IP			)
+	),
+
+	TP_fast_assign(
+		__entry->nbytes		= nbytes;
+		__entry->IP		= IP;
+	),
+
+	TP_printk("nbytes %d caller %pF", __entry->nbytes, (void *)__entry->IP)
+);
+
+DECLARE_EVENT_CLASS(random__extract_entropy,
+	TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
+		 unsigned long IP),
+
+	TP_ARGS(pool_name, nbytes, entropy_count, IP),
+
+	TP_STRUCT__entry(
+		__field( const char *,	pool_name		)
+		__field(	  int,	nbytes			)
+		__field(	  int,	entropy_count		)
+		__field(unsigned long,	IP			)
+	),
+
+	TP_fast_assign(
+		__entry->pool_name	= pool_name;
+		__entry->nbytes		= nbytes;
+		__entry->entropy_count	= entropy_count;
+		__entry->IP		= IP;
+	),
+
+	TP_printk("%s pool: nbytes %d entropy_count %d caller %pF",
+		  __entry->pool_name, __entry->nbytes, __entry->entropy_count,
+		  (void *)__entry->IP)
+);
+
+
+DEFINE_EVENT(random__extract_entropy, extract_entropy,
+	TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
+		 unsigned long IP),
+
+	TP_ARGS(pool_name, nbytes, entropy_count, IP)
+);
+
+DEFINE_EVENT(random__extract_entropy, extract_entropy_user,
+	TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
+		 unsigned long IP),
+
+	TP_ARGS(pool_name, nbytes, entropy_count, IP)
+);
+
+
+
+#endif /* _TRACE_RANDOM_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -117,7 +117,7 @@ irqreturn_t
 handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
 {
 	irqreturn_t retval = IRQ_NONE;
-	unsigned int random = 0, irq = desc->irq_data.irq;
+	unsigned int flags = 0, irq = desc->irq_data.irq;
 
 	do {
 		irqreturn_t res;
@@ -145,7 +145,7 @@ handle_irq_event_percpu(struct irq_desc
 
 			/* Fall through to add to randomness */
 		case IRQ_HANDLED:
-			random |= action->flags;
+			flags |= action->flags;
 			break;
 
 		default:
@@ -156,8 +156,7 @@ handle_irq_event_percpu(struct irq_desc
 		action = action->next;
 	} while (action);
 
-	if (random & IRQF_SAMPLE_RANDOM)
-		add_interrupt_randomness(irq);
+	add_interrupt_randomness(irq, flags);
 
 	if (!noirqdebug)
 		note_interrupt(irq, desc, retval);
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1176,6 +1176,7 @@ static int __dev_open(struct net_device
 		net_dmaengine_get();
 		dev_set_rx_mode(dev);
 		dev_activate(dev);
+		add_device_randomness(dev->dev_addr, dev->addr_len);
 	}
 
 	return ret;
@@ -4823,6 +4824,7 @@ int dev_set_mac_address(struct net_devic
 	err = ops->ndo_set_mac_address(dev, sa);
 	if (!err)
 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
+	add_device_randomness(dev->dev_addr, dev->addr_len);
 	return err;
 }
 EXPORT_SYMBOL(dev_set_mac_address);
@@ -5602,6 +5604,7 @@ int register_netdevice(struct net_device
 	dev_init_scheduler(dev);
 	dev_hold(dev);
 	list_netdevice(dev);
+	add_device_randomness(dev->dev_addr, dev->addr_len);
 
 	/* Notify protocols, that a new device appeared. */
 	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1371,6 +1371,7 @@ static int do_setlink(struct net_device
 			goto errout;
 		send_addr_notify = 1;
 		modified = 1;
+		add_device_randomness(dev->dev_addr, dev->addr_len);
 	}
 
 	if (tb[IFLA_MTU]) {