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-rw-r--r--drivers/char/hw_random/exynos-rng.c9
-rw-r--r--drivers/char/ipmi/ipmi_msghandler.c8
-rw-r--r--drivers/char/random.c42
3 files changed, 41 insertions, 18 deletions
diff --git a/drivers/char/hw_random/exynos-rng.c b/drivers/char/hw_random/exynos-rng.c
index aa30af5f0f2b..7845a38b6604 100644
--- a/drivers/char/hw_random/exynos-rng.c
+++ b/drivers/char/hw_random/exynos-rng.c
@@ -118,6 +118,7 @@ static int exynos_rng_probe(struct platform_device *pdev)
{
struct exynos_rng *exynos_rng;
struct resource *res;
+ int ret;
exynos_rng = devm_kzalloc(&pdev->dev, sizeof(struct exynos_rng),
GFP_KERNEL);
@@ -145,7 +146,13 @@ static int exynos_rng_probe(struct platform_device *pdev)
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_enable(&pdev->dev);
- return devm_hwrng_register(&pdev->dev, &exynos_rng->rng);
+ ret = devm_hwrng_register(&pdev->dev, &exynos_rng->rng);
+ if (ret) {
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ }
+
+ return ret;
}
#ifdef CONFIG_PM
diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index e3536da05c88..a084a4751fa9 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -3819,6 +3819,7 @@ static void handle_new_recv_msgs(ipmi_smi_t intf)
while (!list_empty(&intf->waiting_rcv_msgs)) {
smi_msg = list_entry(intf->waiting_rcv_msgs.next,
struct ipmi_smi_msg, link);
+ list_del(&smi_msg->link);
if (!run_to_completion)
spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
flags);
@@ -3828,11 +3829,14 @@ static void handle_new_recv_msgs(ipmi_smi_t intf)
if (rv > 0) {
/*
* To preserve message order, quit if we
- * can't handle a message.
+ * can't handle a message. Add the message
+ * back at the head, this is safe because this
+ * tasklet is the only thing that pulls the
+ * messages.
*/
+ list_add(&smi_msg->link, &intf->waiting_rcv_msgs);
break;
} else {
- list_del(&smi_msg->link);
if (rv == 0)
/* Message handled */
ipmi_free_smi_msg(smi_msg);
diff --git a/drivers/char/random.c b/drivers/char/random.c
index d0da5d852d41..491a4dce13fe 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -722,15 +722,18 @@ retry:
}
}
-static void credit_entropy_bits_safe(struct entropy_store *r, int nbits)
+static int credit_entropy_bits_safe(struct entropy_store *r, int nbits)
{
const int nbits_max = (int)(~0U >> (ENTROPY_SHIFT + 1));
+ if (nbits < 0)
+ return -EINVAL;
+
/* Cap the value to avoid overflows */
nbits = min(nbits, nbits_max);
- nbits = max(nbits, -nbits_max);
credit_entropy_bits(r, nbits);
+ return 0;
}
/*********************************************************************
@@ -945,6 +948,7 @@ void add_interrupt_randomness(int irq, int irq_flags)
/* award one bit for the contents of the fast pool */
credit_entropy_bits(r, credit + 1);
}
+EXPORT_SYMBOL_GPL(add_interrupt_randomness);
#ifdef CONFIG_BLOCK
void add_disk_randomness(struct gendisk *disk)
@@ -1457,12 +1461,16 @@ random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
static ssize_t
urandom_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
{
+ static int maxwarn = 10;
int ret;
- if (unlikely(nonblocking_pool.initialized == 0))
- printk_once(KERN_NOTICE "random: %s urandom read "
- "with %d bits of entropy available\n",
- current->comm, nonblocking_pool.entropy_total);
+ if (unlikely(nonblocking_pool.initialized == 0) &&
+ maxwarn > 0) {
+ maxwarn--;
+ printk(KERN_NOTICE "random: %s: uninitialized urandom read "
+ "(%zd bytes read, %d bits of entropy available)\n",
+ current->comm, nbytes, nonblocking_pool.entropy_total);
+ }
nbytes = min_t(size_t, nbytes, INT_MAX >> (ENTROPY_SHIFT + 3));
ret = extract_entropy_user(&nonblocking_pool, buf, nbytes);
@@ -1542,8 +1550,7 @@ static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
return -EPERM;
if (get_user(ent_count, p))
return -EFAULT;
- credit_entropy_bits_safe(&input_pool, ent_count);
- return 0;
+ return credit_entropy_bits_safe(&input_pool, ent_count);
case RNDADDENTROPY:
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
@@ -1557,8 +1564,7 @@ static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
size);
if (retval < 0)
return retval;
- credit_entropy_bits_safe(&input_pool, ent_count);
- return 0;
+ return credit_entropy_bits_safe(&input_pool, ent_count);
case RNDZAPENTCNT:
case RNDCLEARPOOL:
/*
@@ -1846,12 +1852,18 @@ void add_hwgenerator_randomness(const char *buffer, size_t count,
{
struct entropy_store *poolp = &input_pool;
- /* Suspend writing if we're above the trickle threshold.
- * We'll be woken up again once below random_write_wakeup_thresh,
- * or when the calling thread is about to terminate.
- */
- wait_event_interruptible(random_write_wait, kthread_should_stop() ||
+ if (unlikely(nonblocking_pool.initialized == 0))
+ poolp = &nonblocking_pool;
+ else {
+ /* Suspend writing if we're above the trickle
+ * threshold. We'll be woken up again once below
+ * random_write_wakeup_thresh, or when the calling
+ * thread is about to terminate.
+ */
+ wait_event_interruptible(random_write_wait,
+ kthread_should_stop() ||
ENTROPY_BITS(&input_pool) <= random_write_wakeup_bits);
+ }
mix_pool_bytes(poolp, buffer, count);
credit_entropy_bits(poolp, entropy);
}