[dpdk-stable] [PATCH] eal: fix unitialized data warning

[David Marchand]

On Wed, Nov 27, 2019 at 11:32 PM Stephen Hemminger
<stephen at networkplumber.org> wrote:
>
> Valgrind reports that eal interrupt thread is calling epoll_ctl
> with uninitialized data.  Trivial to fix by initializing it.
>
> Fixes: af75078fece3 ("first public release")
> Cc: stable at dpdk.org
> Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
> ---
>  lib/librte_eal/linux/eal/eal_interrupts.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/librte_eal/linux/eal/eal_interrupts.c b/lib/librte_eal/linux/eal/eal_interrupts.c
> index 1955324d3045..2cd537ba4492 100644
> --- a/lib/librte_eal/linux/eal/eal_interrupts.c
> +++ b/lib/librte_eal/linux/eal/eal_interrupts.c
> @@ -1045,7 +1045,7 @@ eal_intr_handle_interrupts(int pfd, unsigned totalfds)
>  static __attribute__((noreturn)) void *
>  eal_intr_thread_main(__rte_unused void *arg)
>  {
> -       struct epoll_event ev;
> +       struct epoll_event ev = { };
>
>         /* host thread, never break out */
>         for (;;) {

typedef union epoll_data
{
  void *ptr;
  int fd;
  uint32_t u32;
  uint64_t u64;
} epoll_data_t;

struct epoll_event
{
  uint32_t events;      /* Epoll events */
  epoll_data_t data;    /* User data variable */
} __EPOLL_PACKED;


static __attribute__((noreturn)) void *
eal_intr_thread_main(__rte_unused void *arg)
{
        struct epoll_event ev;
[...]
                        ev.events = EPOLLIN | EPOLLPRI | EPOLLRDHUP | EPOLLHUP;
                        ev.data.fd = src->intr_handle.fd;
[...]
                        if (epoll_ctl(pfd, EPOLL_CTL_ADD,
                                        src->intr_handle.fd, &ev) < 0){

So the uninitialised part is because we only set an int in the union.
False positive from valgrind, but the fix is quite simple.

Acked-by: David Marchand <david.marchand at redhat.com>


-- 
David Marchand