PRINTF_BUFFER_SIZE
printf_buffer = kmem_alloc(PRINTF_BUFFER_SIZE, KM_SLEEP);
(void) snprintf(printf_buffer, PRINTF_BUFFER_SIZE, "%d ", err);
ret = vsnprintf(printf_buffer+len, PRINTF_BUFFER_SIZE-len, fmt, ap);
ASSERT(len + ret <= PRINTF_BUFFER_SIZE-1);
kmem_free(printf_buffer, PRINTF_BUFFER_SIZE);
printf_buffer = kmem_alloc(PRINTF_BUFFER_SIZE, KM_SLEEP);
ret = vsnprintf(printf_buffer, PRINTF_BUFFER_SIZE, fmt, ap);
ASSERT(ret <= PRINTF_BUFFER_SIZE-1);
kmem_free(printf_buffer, PRINTF_BUFFER_SIZE);