diff options
Diffstat (limited to 'drivers/char/random.c')
| -rw-r--r-- | drivers/char/random.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 1822472dffab..bd9fc2baa6aa 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -886,12 +886,16 @@ static void add_interrupt_bench(cycles_t start) static __u32 get_reg(struct fast_pool *f, struct pt_regs *regs) { __u32 *ptr = (__u32 *) regs; + unsigned int idx; if (regs == NULL) return 0; - if (f->reg_idx >= sizeof(struct pt_regs) / sizeof(__u32)) - f->reg_idx = 0; - return *(ptr + f->reg_idx++); + idx = READ_ONCE(f->reg_idx); + if (idx >= sizeof(struct pt_regs) / sizeof(__u32)) + idx = 0; + ptr += idx++; + WRITE_ONCE(f->reg_idx, idx); + return *ptr; } void add_interrupt_randomness(int irq, int irq_flags) |