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From: Luca Boccassi <bluca@debian.org>
To: dev@dpdk.org
Cc: maxime.coquelin@redhat.com, tiwei.bie@intel.com,
	yongwang@vmware.com, 3chas3@gmail.com,
	bruce.richardson@intel.com, jianfeng.tan@intel.com,
	anatoly.burakov@intel.com, llouis@vmware.com,
	brussell@vyatta.att-mail.com
Subject: [dpdk-dev] [PATCH v2 3/3] eal/linux: handle uio read failure in interrupt handler
Date: Wed, 19 Sep 2018 13:57:57 +0100	[thread overview]
Message-ID: <20180919125757.17938-3-bluca@debian.org> (raw)
In-Reply-To: <20180919125757.17938-1-bluca@debian.org>

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: stable@dpdk.org

Signed-off-by: Brian Russell <brussell@brocade.com>
Signed-off-by: Luca Boccassi <bluca@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);
-- 
2.18.0

  parent reply	other threads:[~2018-09-19 12:58 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-08-16 13:50 [dpdk-dev] [PATCH 0/3] Fix hot plug/unplug of virtual devices Luca Boccassi
2018-08-16 13:50 ` [dpdk-dev] [PATCH 1/3] net/virtio: register/unregister intr handler on start/stop Luca Boccassi
2018-08-16 13:50 ` [dpdk-dev] [PATCH 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug Luca Boccassi
2018-09-17 19:06   ` Louis Luo
2018-09-18 13:14     ` Luca Boccassi
2018-09-18 18:14       ` Louis Luo
2018-09-18 18:29         ` Luca Boccassi
2018-09-18 18:48           ` Louis Luo
2018-09-19 12:58             ` Luca Boccassi
2018-08-16 13:50 ` [dpdk-dev] [PATCH 3/3] eal/linux: handle uio read failure in interrupt handler Luca Boccassi
2018-09-19 12:57 ` [dpdk-dev] [PATCH v2 1/3] net/virtio: register/unregister intr handler on start/stop Luca Boccassi
2018-09-19 12:57   ` [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug Luca Boccassi
2018-09-19 15:47     ` Chas Williams
2018-09-19 16:08       ` Luca Boccassi
2018-10-27 15:09       ` Thomas Monjalon
2018-10-31 17:27         ` Thomas Monjalon
2018-10-31 17:46           ` Luca Boccassi
2018-10-31 18:02             ` Thomas Monjalon
2018-10-31 18:54             ` Louis Luo
2018-09-27  8:39     ` Luca Boccassi
2018-09-19 12:57   ` Luca Boccassi [this message]
2018-10-11 10:32     ` [dpdk-dev] [PATCH v2 3/3] eal/linux: handle uio read failure in interrupt handler Thomas Monjalon
2018-09-27  8:40   ` [dpdk-dev] [PATCH v2 1/3] net/virtio: register/unregister intr handler on start/stop Luca Boccassi
2018-09-27 10:51     ` Maxime Coquelin
2018-09-27 11:14   ` Maxime Coquelin
2018-10-31 18:39 ` [dpdk-dev] [PATCH v3 " Luca Boccassi
2018-10-31 18:39   ` [dpdk-dev] [PATCH v3 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug Luca Boccassi
2018-10-31 18:39   ` [dpdk-dev] [PATCH v3 3/3] eal/linux: handle uio read failure in interrupt handler Luca Boccassi
2018-11-02  9:49   ` [dpdk-dev] [dpdk-stable] [PATCH v3 1/3] net/virtio: register/unregister intr handler on start/stop Thomas Monjalon
2018-11-02 11:14     ` Luca Boccassi

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