Looking for someone to review this patch please
19/09/2018 14:57, Luca Boccassi:
> If a device is unplugged while an interrupt is pending, the
> read call to the uio device to remove it from the poll wait list
> can fail resulting in it being continually polled forever. This
> change checks for the read failing and if so, unregisters the device
> as an interrupt source and causes the wait list to be rebuilt.
>
> This race has been reported and observed in production.
>
> Fixes: 0a45657a6794 ("pci: rework interrupt handling")
> Cc: sta...@dpdk.org
>
> Signed-off-by: Brian Russell <bruss...@brocade.com>
> Signed-off-by: Luca Boccassi <bl...@debian.org>
> ---
> lib/librte_eal/linuxapp/eal/eal_interrupts.c | 19 ++++++++++++++++++-
> 1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/lib/librte_eal/linuxapp/eal/eal_interrupts.c
> b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
> index 4076c6d6ca..34584db883 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_interrupts.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
> @@ -627,7 +627,7 @@ eal_intr_process_interrupts(struct epoll_event *events,
> int nfds)
> bool call = false;
> int n, bytes_read;
> struct rte_intr_source *src;
> - struct rte_intr_callback *cb;
> + struct rte_intr_callback *cb, *next;
> union rte_intr_read_buffer buf;
> struct rte_intr_callback active_cb;
>
> @@ -701,6 +701,23 @@ eal_intr_process_interrupts(struct epoll_event *events,
> int nfds)
> "descriptor %d: %s\n",
> events[n].data.fd,
> strerror(errno));
> + /*
> + * The device is unplugged or buggy, remove
> + * it as an interrupt source and return to
> + * force the wait list to be rebuilt.
> + */
> + rte_spinlock_lock(&intr_lock);
> + TAILQ_REMOVE(&intr_sources, src, next);
> + rte_spinlock_unlock(&intr_lock);
> +
> + for (cb = TAILQ_FIRST(&src->callbacks); cb;
> + cb = next) {
> + next = TAILQ_NEXT(cb, next);
> + TAILQ_REMOVE(&src->callbacks, cb, next);
> + free(cb);
> + }
> + free(src);
> + return -1;
> } else if (bytes_read == 0)
> RTE_LOG(ERR, EAL, "Read nothing from file "
> "descriptor %d\n", events[n].data.fd);
>
