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-rw-r--r--drivers/char/random.c10
-rw-r--r--include/linux/irqdesc.h1
-rw-r--r--include/linux/random.h2
-rw-r--r--kernel/irq/handle.c8
-rw-r--r--kernel/irq/manage.c6
5 files changed, 21 insertions, 6 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 6d33427..8f1489c 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -739,18 +739,16 @@ EXPORT_SYMBOL_GPL(add_input_randomness);
static DEFINE_PER_CPU(struct fast_pool, irq_randomness);
-void add_interrupt_randomness(int irq, int irq_flags)
+void add_interrupt_randomness(int irq, int irq_flags, __u64 ip)
{
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 = random_get_entropy();
input[0] = cycles ^ jiffies;
input[1] = irq;
- if (regs) {
- __u64 ip = instruction_pointer(regs);
+ if (ip) {
input[2] = ip;
input[3] = ip >> 32;
}
@@ -764,7 +762,11 @@ void add_interrupt_randomness(int irq, int irq_flags)
fast_pool->last = now;
r = nonblocking_pool.initialized ? &input_pool : &nonblocking_pool;
+#ifndef CONFIG_PREEMPT_RT_FULL
__mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool), NULL);
+#else
+ mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool), NULL);
+#endif
/*
* If we don't have a valid cycle counter, and we see
* back-to-back timer interrupts, then skip giving credit for
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index a7b4b61..6686311 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -56,6 +56,7 @@ struct irq_desc {
unsigned int irqs_unhandled;
atomic_t threads_handled;
int threads_handled_last;
+ u64 random_ip;
raw_spinlock_t lock;
struct cpumask *percpu_enabled;
#ifdef CONFIG_SMP
diff --git a/include/linux/random.h b/include/linux/random.h
index bf9085e..de4894a 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -12,7 +12,7 @@
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, int irq_flags);
+extern void add_interrupt_randomness(int irq, int irq_flags, __u64 ip);
extern void get_random_bytes(void *buf, int nbytes);
extern void get_random_bytes_arch(void *buf, int nbytes);
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 131ca17..7f50c55 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -132,6 +132,8 @@ static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action)
irqreturn_t
handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
{
+ struct pt_regs *regs = get_irq_regs();
+ u64 ip = regs ? instruction_pointer(regs) : 0;
irqreturn_t retval = IRQ_NONE;
unsigned int flags = 0, irq = desc->irq_data.irq;
@@ -172,7 +174,11 @@ handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
action = action->next;
} while (action);
- add_interrupt_randomness(irq, flags);
+#ifndef CONFIG_PREEMPT_RT_FULL
+ add_interrupt_randomness(irq, flags, ip);
+#else
+ desc->random_ip = ip;
+#endif
if (!noirqdebug)
note_interrupt(irq, desc, retval);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 037d2cd..11be231 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -942,6 +942,12 @@ static int irq_thread(void *data)
if (action_ret == IRQ_HANDLED)
atomic_inc(&desc->threads_handled);
+#ifdef CONFIG_PREEMPT_RT_FULL
+ migrate_disable();
+ add_interrupt_randomness(action->irq, 0,
+ desc->random_ip ^ (unsigned long) action);
+ migrate_enable();
+#endif
wake_threads_waitq(desc);
}