[dpdk-dev] [PATCH 0/3] Fix hot plug/unplug of virtual devices

[dpdk-dev] [PATCH 0/3] Fix hot plug/unplug of virtual devices

[Luca Boccassi]

Although not very common and perhaps a bit strange, we do have users
that want to be able to hot plug/unplug virtio or vmxnet devices from
a running system, without shutting down the application nor the VM.

We have been enabling this in production for a year or so, so it's well
tested. The only issues found so far are fixed by this series.

Luca Boccassi (3):
  net/virtio: register/unregister intr handler on start/stop
  net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug
  eal/linux: handle uio read failure in interrupt handler

 drivers/net/virtio/virtio_ethdev.c           | 26 ++++++++------
 drivers/net/vmxnet3/vmxnet3_ethdev.c         | 36 ++++++++++++++------
 lib/librte_eal/linuxapp/eal/eal_interrupts.c | 19 ++++++++++-
 3 files changed, 59 insertions(+), 22 deletions(-)

-- 
2.18.0

[dpdk-dev] [PATCH 1/3] net/virtio: register/unregister intr handler on start/stop

[Luca Boccassi]

Register and unregister the virtio interrupt handler when the device is
started and stopped. This allows a virtio device to be hotplugged or
unplugged.

Fixes: c1f86306a026 ("virtio: add new driver")
Cc: stable@dpdk.org

Signed-off-by: Brian Russell <brussell@brocade.com>
Signed-off-by: Luca Boccassi <bluca@debian.org>
---
 drivers/net/virtio/virtio_ethdev.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 614357da74..3195443a1b 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1679,11 +1679,6 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 	if (ret < 0)
 		goto out;
 
-	/* Setup interrupt callback  */
-	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
-		rte_intr_callback_register(eth_dev->intr_handle,
-			virtio_interrupt_handler, eth_dev);
-
 	return 0;
 
 out:
@@ -1709,11 +1704,6 @@ eth_virtio_dev_uninit(struct rte_eth_dev *eth_dev)
 	rte_free(eth_dev->data->mac_addrs);
 	eth_dev->data->mac_addrs = NULL;
 
-	/* reset interrupt callback  */
-	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
-		rte_intr_callback_unregister(eth_dev->intr_handle,
-						virtio_interrupt_handler,
-						eth_dev);
 	if (eth_dev->device)
 		rte_pci_unmap_device(RTE_ETH_DEV_TO_PCI(eth_dev));
 
@@ -1972,6 +1962,12 @@ virtio_dev_start(struct rte_eth_dev *dev)
 	    dev->data->dev_conf.intr_conf.rxq) {
 		virtio_intr_disable(dev);
 
+		/* Setup interrupt callback  */
+		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
+			rte_intr_callback_register(dev->intr_handle,
+						   virtio_interrupt_handler,
+						   dev);
+
 		if (virtio_intr_enable(dev) < 0) {
 			PMD_DRV_LOG(ERR, "interrupt enable failed");
 			return -EIO;
@@ -2081,9 +2077,17 @@ virtio_dev_stop(struct rte_eth_dev *dev)
 	PMD_INIT_LOG(DEBUG, "stop");
 
 	rte_spinlock_lock(&hw->state_lock);
-	if (intr_conf->lsc || intr_conf->rxq)
+	if (intr_conf->lsc || intr_conf->rxq) {
 		virtio_intr_disable(dev);
 
+		/* Reset interrupt callback  */
+		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC) {
+			rte_intr_callback_unregister(dev->intr_handle,
+						     virtio_interrupt_handler,
+						     dev);
+		}
+	}
+
 	hw->started = 0;
 	memset(&link, 0, sizeof(link));
 	rte_eth_linkstatus_set(dev, &link);
-- 
2.18.0

[dpdk-dev] [PATCH 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

The vmxnet3 driver can't call back into dev_close(), and possibly
dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
that those routines would want to clean up has already been released.
Further, for complete cleanup, it is necessary to release any of the
queue resources during dev_close().
This allows a vmxnet3 device to be hot-unplugged without leaking
queues.

Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver implementation")
Cc: stable@dpdk.org

Signed-off-by: Brian Russell <brussell@brocade.com>
Signed-off-by: Luca Boccassi <bluca@debian.org>
---
 drivers/net/vmxnet3/vmxnet3_ethdev.c | 36 ++++++++++++++++++++--------
 1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c b/drivers/net/vmxnet3/vmxnet3_ethdev.c
index 2613cd1358..b5d4be5e24 100644
--- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
+++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
@@ -348,16 +348,11 @@ eth_vmxnet3_dev_init(struct rte_eth_dev *eth_dev)
 static int
 eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
 {
-	struct vmxnet3_hw *hw = eth_dev->data->dev_private;
-
 	PMD_INIT_FUNC_TRACE();
 
 	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
 		return 0;
 
-	if (hw->adapter_stopped == 0)
-		vmxnet3_dev_close(eth_dev);
-
 	eth_dev->dev_ops = NULL;
 	eth_dev->rx_pkt_burst = NULL;
 	eth_dev->tx_pkt_burst = NULL;
@@ -803,7 +798,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	PMD_INIT_FUNC_TRACE();
 
 	if (hw->adapter_stopped == 1) {
-		PMD_INIT_LOG(DEBUG, "Device already closed.");
+		PMD_INIT_LOG(DEBUG, "Device already stopped.");
 		return;
 	}
 
@@ -827,7 +822,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	/* reset the device */
 	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD, VMXNET3_CMD_RESET_DEV);
 	PMD_INIT_LOG(DEBUG, "Device reset.");
-	hw->adapter_stopped = 0;
 
 	vmxnet3_dev_clear_queues(dev);
 
@@ -837,6 +831,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	link.link_speed = ETH_SPEED_NUM_10G;
 	link.link_autoneg = ETH_LINK_FIXED;
 	rte_eth_linkstatus_set(dev, &link);
+
+	hw->adapter_stopped = 1;
+}
+
+static void
+vmxnet3_free_queues(struct rte_eth_dev *dev)
+{
+	int i;
+
+	PMD_INIT_FUNC_TRACE();
+
+	for (i = 0; i < dev->data->nb_rx_queues; i++) {
+		void *rxq = dev->data->rx_queues[i];
+
+		vmxnet3_dev_rx_queue_release(rxq);
+	}
+	dev->data->nb_rx_queues = 0;
+
+	for (i = 0; i < dev->data->nb_tx_queues; i++) {
+		void *txq = dev->data->tx_queues[i];
+
+		vmxnet3_dev_tx_queue_release(txq);
+	}
+	dev->data->nb_tx_queues = 0;
 }
 
 /*
@@ -845,12 +863,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 static void
 vmxnet3_dev_close(struct rte_eth_dev *dev)
 {
-	struct vmxnet3_hw *hw = dev->data->dev_private;
-
 	PMD_INIT_FUNC_TRACE();
 
 	vmxnet3_dev_stop(dev);
-	hw->adapter_stopped = 1;
+	vmxnet3_free_queues(dev);
 }
 
 static void
-- 
2.18.0

[dpdk-dev] [PATCH 3/3] eal/linux: handle uio read failure in interrupt handler

[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: 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

Re: [dpdk-dev] [PATCH 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Louis Luo]

Hi Luca,

When eth_vmxnet3_dev_uninit() is called, is it guaranteed that vmxnet3_dev_close/ vmxnet3_dev_stop must have been called? I'm not familiar with the hot-plug procedure, so just wonder if there is any chance that eth_vmxnet3_dev_uninit() is called without calling vmxnet3_dev_close/ vmxnet3_dev_stop.

Thanks,
Louis

On 8/16/18, 6:51 AM, "dev on behalf of Luca Boccassi" <dev-bounces@dpdk.org on behalf of bluca@debian.org> wrote:

    The vmxnet3 driver can't call back into dev_close(), and possibly
    dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
    that those routines would want to clean up has already been released.
    Further, for complete cleanup, it is necessary to release any of the
    queue resources during dev_close().
    This allows a vmxnet3 device to be hot-unplugged without leaking
    queues.
    
    Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver implementation")
    Cc: stable@dpdk.org
    
    Signed-off-by: Brian Russell <brussell@brocade.com>
    Signed-off-by: Luca Boccassi <bluca@debian.org>
    ---
     drivers/net/vmxnet3/vmxnet3_ethdev.c | 36 ++++++++++++++++++++--------
     1 file changed, 26 insertions(+), 10 deletions(-)
    
    diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c b/drivers/net/vmxnet3/vmxnet3_ethdev.c
    index 2613cd1358..b5d4be5e24 100644
    --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
    +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
    @@ -348,16 +348,11 @@ eth_vmxnet3_dev_init(struct rte_eth_dev *eth_dev)
     static int
     eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
     {
    -	struct vmxnet3_hw *hw = eth_dev->data->dev_private;
    -
     	PMD_INIT_FUNC_TRACE();
     
     	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
     		return 0;
     
    -	if (hw->adapter_stopped == 0)
    -		vmxnet3_dev_close(eth_dev);
    -
     	eth_dev->dev_ops = NULL;
     	eth_dev->rx_pkt_burst = NULL;
     	eth_dev->tx_pkt_burst = NULL;
    @@ -803,7 +798,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
     	PMD_INIT_FUNC_TRACE();
     
     	if (hw->adapter_stopped == 1) {
    -		PMD_INIT_LOG(DEBUG, "Device already closed.");
    +		PMD_INIT_LOG(DEBUG, "Device already stopped.");
     		return;
     	}
     
    @@ -827,7 +822,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
     	/* reset the device */
     	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD, VMXNET3_CMD_RESET_DEV);
     	PMD_INIT_LOG(DEBUG, "Device reset.");
    -	hw->adapter_stopped = 0;
     
     	vmxnet3_dev_clear_queues(dev);
     
    @@ -837,6 +831,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
     	link.link_speed = ETH_SPEED_NUM_10G;
     	link.link_autoneg = ETH_LINK_FIXED;
     	rte_eth_linkstatus_set(dev, &link);
    +
    +	hw->adapter_stopped = 1;
    +}
    +
    +static void
    +vmxnet3_free_queues(struct rte_eth_dev *dev)
    +{
    +	int i;
    +
    +	PMD_INIT_FUNC_TRACE();
    +
    +	for (i = 0; i < dev->data->nb_rx_queues; i++) {
    +		void *rxq = dev->data->rx_queues[i];
    +
    +		vmxnet3_dev_rx_queue_release(rxq);
    +	}
    +	dev->data->nb_rx_queues = 0;
    +
    +	for (i = 0; i < dev->data->nb_tx_queues; i++) {
    +		void *txq = dev->data->tx_queues[i];
    +
    +		vmxnet3_dev_tx_queue_release(txq);
    +	}
    +	dev->data->nb_tx_queues = 0;
     }
     
     /*
    @@ -845,12 +863,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
     static void
     vmxnet3_dev_close(struct rte_eth_dev *dev)
     {
    -	struct vmxnet3_hw *hw = dev->data->dev_private;
    -
     	PMD_INIT_FUNC_TRACE();
     
     	vmxnet3_dev_stop(dev);
    -	hw->adapter_stopped = 1;
    +	vmxnet3_free_queues(dev);
     }
     
     static void
    -- 
    2.18.0
    
    

Re: [dpdk-dev] [PATCH 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

Hi,

The application must already stop and close before detaching (which
will call uninit). Quoting from the documentation:

"*  Before detaching, they must be stopped and closed.

    DPDK applications must call "rte_eth_dev_stop()" and
    "rte_eth_dev_close()" APIs before detaching ports. These functions will
    start finalization sequence of the PMDs."

http://doc.dpdk.org/guides/prog_guide/port_hotplug_framework.html

On Mon, 2018-09-17 at 19:06 +0000, Louis Luo wrote:
> Hi Luca,
> 
> When eth_vmxnet3_dev_uninit() is called, is it guaranteed that
> vmxnet3_dev_close/ vmxnet3_dev_stop must have been called? I'm not
> familiar with the hot-plug procedure, so just wonder if there is any
> chance that eth_vmxnet3_dev_uninit() is called without calling
> vmxnet3_dev_close/ vmxnet3_dev_stop.
> 
> Thanks,
> Louis
> 
> On 8/16/18, 6:51 AM, "dev on behalf of Luca Boccassi" <dev-bounces@d
> pdk.org on behalf of bluca@debian.org> wrote:
> 
>     The vmxnet3 driver can't call back into dev_close(), and possibly
>     dev_stop(), in dev_uninit().  When dev_uninit() is called,
> anything
>     that those routines would want to clean up has already been
> released.
>     Further, for complete cleanup, it is necessary to release any of
> the
>     queue resources during dev_close().
>     This allows a vmxnet3 device to be hot-unplugged without leaking
>     queues.
>     
>     Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode
> driver implementation")
>     Cc: stable@dpdk.org
>     
>     Signed-off-by: Brian Russell <brussell@brocade.com>
>     Signed-off-by: Luca Boccassi <bluca@debian.org>
>     ---
>      drivers/net/vmxnet3/vmxnet3_ethdev.c | 36 ++++++++++++++++++++
> --------
>      1 file changed, 26 insertions(+), 10 deletions(-)
>     
>     diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> b/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     index 2613cd1358..b5d4be5e24 100644
>     --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     @@ -348,16 +348,11 @@ eth_vmxnet3_dev_init(struct rte_eth_dev
> *eth_dev)
>      static int
>      eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
>      {
>     -	struct vmxnet3_hw *hw = eth_dev->data->dev_private;
>     -
>      	PMD_INIT_FUNC_TRACE();
>      
>      	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
>      		return 0;
>      
>     -	if (hw->adapter_stopped == 0)
>     -		vmxnet3_dev_close(eth_dev);
>     -
>      	eth_dev->dev_ops = NULL;
>      	eth_dev->rx_pkt_burst = NULL;
>      	eth_dev->tx_pkt_burst = NULL;
>     @@ -803,7 +798,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>      	PMD_INIT_FUNC_TRACE();
>      
>      	if (hw->adapter_stopped == 1) {
>     -		PMD_INIT_LOG(DEBUG, "Device already closed.");
>     +		PMD_INIT_LOG(DEBUG, "Device already stopped.");
>      		return;
>      	}
>      
>     @@ -827,7 +822,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>      	/* reset the device */
>      	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD,
> VMXNET3_CMD_RESET_DEV);
>      	PMD_INIT_LOG(DEBUG, "Device reset.");
>     -	hw->adapter_stopped = 0;
>      
>      	vmxnet3_dev_clear_queues(dev);
>      
>     @@ -837,6 +831,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>      	link.link_speed = ETH_SPEED_NUM_10G;
>      	link.link_autoneg = ETH_LINK_FIXED;
>      	rte_eth_linkstatus_set(dev, &link);
>     +
>     +	hw->adapter_stopped = 1;
>     +}
>     +
>     +static void
>     +vmxnet3_free_queues(struct rte_eth_dev *dev)
>     +{
>     +	int i;
>     +
>     +	PMD_INIT_FUNC_TRACE();
>     +
>     +	for (i = 0; i < dev->data->nb_rx_queues; i++) {
>     +		void *rxq = dev->data->rx_queues[i];
>     +
>     +		vmxnet3_dev_rx_queue_release(rxq);
>     +	}
>     +	dev->data->nb_rx_queues = 0;
>     +
>     +	for (i = 0; i < dev->data->nb_tx_queues; i++) {
>     +		void *txq = dev->data->tx_queues[i];
>     +
>     +		vmxnet3_dev_tx_queue_release(txq);
>     +	}
>     +	dev->data->nb_tx_queues = 0;
>      }
>      
>      /*
>     @@ -845,12 +863,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>      static void
>      vmxnet3_dev_close(struct rte_eth_dev *dev)
>      {
>     -	struct vmxnet3_hw *hw = dev->data->dev_private;
>     -
>      	PMD_INIT_FUNC_TRACE();
>      
>      	vmxnet3_dev_stop(dev);
>     -	hw->adapter_stopped = 1;
>     +	vmxnet3_free_queues(dev);
>      }
>      
>      static void
>     -- 
>     2.18.0
>     
>     
> 

-- 
Kind regards,
Luca Boccassi

Re: [dpdk-dev] [PATCH 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Louis Luo]

Hi Luca,

Thanks for pointing to the document! This "basic requirements" seems to lay the burden on application developers to correctly follow the hot-plug framework's rules, but there seems no mechanism to enforce this procedure (correct me if I'm wrong). What if a buggy application doesn't call stop/close before detaching? 

In addition, in your commit description, you said " The vmxnet3 driver can't call back into dev_close(), and possibly dev_stop(), in dev_uninit()." But actually in vmxnet3_dev_close(), we set hw->adapter_stopped = 1, and in eth_vmxnet3_dev_uninit() we call into vmxnet3_dev_close() ONLY when hw->adapter_stopped == 0. So if the application does meet the hot-plug framework requirement and calls dev_close before calling uninit, eth_vmxnet3_dev_uninit() should not call into vmxnet3_dev_close() again, right? If so, why bother removing this check? 

Or let me ask this way. If a buggy application DOES NOT call dev_close before calling eth_vmxnet3_dev_uninit(), would calling vmxnet3_dev_close() inside eth_vmxnet3_dev_uninit() cause any trouble? And if an application DOES call dev_close before calling eth_vmxnet3_dev_uninit(), have you ever seen vmxnet3_dev_close() being called again and trigger crashes like double-free or something else? If yes, then we need to investigate.

Thanks
Louis

On 9/18/18, 6:15 AM, "Luca Boccassi" <bluca@debian.org> wrote:

    Hi,
    
    The application must already stop and close before detaching (which
    will call uninit). Quoting from the documentation:
    
    "*  Before detaching, they must be stopped and closed.
    
        DPDK applications must call "rte_eth_dev_stop()" and
        "rte_eth_dev_close()" APIs before detaching ports. These functions will
        start finalization sequence of the PMDs."
    
    https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdoc.dpdk.org%2Fguides%2Fprog_guide%2Fport_hotplug_framework.html&amp;data=02%7C01%7Cllouis%40vmware.com%7C3d87a5482cd046679d7608d61d68bf9a%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C1%7C0%7C636728733078700911&amp;sdata=qBx7zyOJhTmVH0c2ZEBohmIHL6PkYwB6XPaw2epgS0E%3D&amp;reserved=0
    
    On Mon, 2018-09-17 at 19:06 +0000, Louis Luo wrote:
    > Hi Luca,
    > 
    > When eth_vmxnet3_dev_uninit() is called, is it guaranteed that
    > vmxnet3_dev_close/ vmxnet3_dev_stop must have been called? I'm not
    > familiar with the hot-plug procedure, so just wonder if there is any
    > chance that eth_vmxnet3_dev_uninit() is called without calling
    > vmxnet3_dev_close/ vmxnet3_dev_stop.
    > 
    > Thanks,
    > Louis
    > 
    > On 8/16/18, 6:51 AM, "dev on behalf of Luca Boccassi" <dev-bounces@d
    > pdk.org on behalf of bluca@debian.org> wrote:
    > 
    >     The vmxnet3 driver can't call back into dev_close(), and possibly
    >     dev_stop(), in dev_uninit().  When dev_uninit() is called,
    > anything
    >     that those routines would want to clean up has already been
    > released.
    >     Further, for complete cleanup, it is necessary to release any of
    > the
    >     queue resources during dev_close().
    >     This allows a vmxnet3 device to be hot-unplugged without leaking
    >     queues.
    >     
    >     Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode
    > driver implementation")
    >     Cc: stable@dpdk.org
    >     
    >     Signed-off-by: Brian Russell <brussell@brocade.com>
    >     Signed-off-by: Luca Boccassi <bluca@debian.org>
    >     ---
    >      drivers/net/vmxnet3/vmxnet3_ethdev.c | 36 ++++++++++++++++++++
    > --------
    >      1 file changed, 26 insertions(+), 10 deletions(-)
    >     
    >     diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
    > b/drivers/net/vmxnet3/vmxnet3_ethdev.c
    >     index 2613cd1358..b5d4be5e24 100644
    >     --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
    >     +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
    >     @@ -348,16 +348,11 @@ eth_vmxnet3_dev_init(struct rte_eth_dev
    > *eth_dev)
    >      static int
    >      eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
    >      {
    >     -	struct vmxnet3_hw *hw = eth_dev->data->dev_private;
    >     -
    >      	PMD_INIT_FUNC_TRACE();
    >      
    >      	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
    >      		return 0;
    >      
    >     -	if (hw->adapter_stopped == 0)
    >     -		vmxnet3_dev_close(eth_dev);
    >     -
    >      	eth_dev->dev_ops = NULL;
    >      	eth_dev->rx_pkt_burst = NULL;
    >      	eth_dev->tx_pkt_burst = NULL;
    >     @@ -803,7 +798,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
    >      	PMD_INIT_FUNC_TRACE();
    >      
    >      	if (hw->adapter_stopped == 1) {
    >     -		PMD_INIT_LOG(DEBUG, "Device already closed.");
    >     +		PMD_INIT_LOG(DEBUG, "Device already stopped.");
    >      		return;
    >      	}
    >      
    >     @@ -827,7 +822,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
    >      	/* reset the device */
    >      	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD,
    > VMXNET3_CMD_RESET_DEV);
    >      	PMD_INIT_LOG(DEBUG, "Device reset.");
    >     -	hw->adapter_stopped = 0;
    >      
    >      	vmxnet3_dev_clear_queues(dev);
    >      
    >     @@ -837,6 +831,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
    >      	link.link_speed = ETH_SPEED_NUM_10G;
    >      	link.link_autoneg = ETH_LINK_FIXED;
    >      	rte_eth_linkstatus_set(dev, &link);
    >     +
    >     +	hw->adapter_stopped = 1;
    >     +}
    >     +
    >     +static void
    >     +vmxnet3_free_queues(struct rte_eth_dev *dev)
    >     +{
    >     +	int i;
    >     +
    >     +	PMD_INIT_FUNC_TRACE();
    >     +
    >     +	for (i = 0; i < dev->data->nb_rx_queues; i++) {
    >     +		void *rxq = dev->data->rx_queues[i];
    >     +
    >     +		vmxnet3_dev_rx_queue_release(rxq);
    >     +	}
    >     +	dev->data->nb_rx_queues = 0;
    >     +
    >     +	for (i = 0; i < dev->data->nb_tx_queues; i++) {
    >     +		void *txq = dev->data->tx_queues[i];
    >     +
    >     +		vmxnet3_dev_tx_queue_release(txq);
    >     +	}
    >     +	dev->data->nb_tx_queues = 0;
    >      }
    >      
    >      /*
    >     @@ -845,12 +863,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
    >      static void
    >      vmxnet3_dev_close(struct rte_eth_dev *dev)
    >      {
    >     -	struct vmxnet3_hw *hw = dev->data->dev_private;
    >     -
    >      	PMD_INIT_FUNC_TRACE();
    >      
    >      	vmxnet3_dev_stop(dev);
    >     -	hw->adapter_stopped = 1;
    >     +	vmxnet3_free_queues(dev);
    >      }
    >      
    >      static void
    >     -- 
    >     2.18.0
    >     
    >     
    > 
    
    -- 
    Kind regards,
    Luca Boccassi

Re: [dpdk-dev] [PATCH 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

On Tue, 2018-09-18 at 18:14 +0000, Louis Luo wrote:
> Hi Luca,
> 
> Thanks for pointing to the document! This "basic requirements" seems
> to lay the burden on application developers to correctly follow the
> hot-plug framework's rules, but there seems no mechanism to enforce
> this procedure (correct me if I'm wrong). What if a buggy application
> doesn't call stop/close before detaching? 

Well DPDK in general does not have the simplest API to use, there's no
denying that. That's because what it does is very much more complicated
than the average library.
So if an application ignores the development guides and does not follow
the recommendation bad things will happen :-) But it will happen
regardless of the PMD used. That's already the case.

> In addition, in your commit description, you said " The vmxnet3
> driver can't call back into dev_close(), and possibly dev_stop(), in
> dev_uninit()." But actually in vmxnet3_dev_close(), we set hw-
> >adapter_stopped = 1, and in eth_vmxnet3_dev_uninit() we call into
> vmxnet3_dev_close() ONLY when hw->adapter_stopped == 0. So if the
> application does meet the hot-plug framework requirement and calls
> dev_close before calling uninit, eth_vmxnet3_dev_uninit() should not
> call into vmxnet3_dev_close() again, right? If so, why bother
> removing this check? 
> 
> Or let me ask this way. If a buggy application DOES NOT call
> dev_close before calling eth_vmxnet3_dev_uninit(), would calling
> vmxnet3_dev_close() inside eth_vmxnet3_dev_uninit() cause any
> trouble? And if an application DOES call dev_close before calling
> eth_vmxnet3_dev_uninit(), have you ever seen vmxnet3_dev_close()
> being called again and trigger crashes like double-free or something
> else? If yes, then we need to investigate.
> 
> Thanks
> Louis

The problem is that there are many PMDs, so the guidelines have to be
followed - so stop and close have to be called anyway before detach.
Otherwise running with other PMDs will break the application. So not
calling close is not really an option for an application.

But the main issue here is the leaking of the queues, which this patch
fixes. By re-arranging the stop/close/uninit like this, queues can be
correctly freed and thus we can hotplug/unplug devices without leaking
massive amounts of memory.

My colleague Brian, who wrote the patch and I CC'ed, might have more
information if you need it.

> On 9/18/18, 6:15 AM, "Luca Boccassi" <bluca@debian.org> wrote:
> 
>     Hi,
>     
>     The application must already stop and close before detaching
> (which
>     will call uninit). Quoting from the documentation:
>     
>     "*  Before detaching, they must be stopped and closed.
>     
>         DPDK applications must call "rte_eth_dev_stop()" and
>         "rte_eth_dev_close()" APIs before detaching ports. These
> functions will
>         start finalization sequence of the PMDs."
>     
>     https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fd
> oc.dpdk.org%2Fguides%2Fprog_guide%2Fport_hotplug_framework.html&amp;d
> ata=02%7C01%7Cllouis%40vmware.com%7C3d87a5482cd046679d7608d61d68bf9a%
> 7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C1%7C0%7C636728733078700911&amp;s
> data=qBx7zyOJhTmVH0c2ZEBohmIHL6PkYwB6XPaw2epgS0E%3D&amp;reserved=0
>     
>     On Mon, 2018-09-17 at 19:06 +0000, Louis Luo wrote:
>     > Hi Luca,
>     > 
>     > When eth_vmxnet3_dev_uninit() is called, is it guaranteed that
>     > vmxnet3_dev_close/ vmxnet3_dev_stop must have been called? I'm
> not
>     > familiar with the hot-plug procedure, so just wonder if there
> is any
>     > chance that eth_vmxnet3_dev_uninit() is called without calling
>     > vmxnet3_dev_close/ vmxnet3_dev_stop.
>     > 
>     > Thanks,
>     > Louis
>     > 
>     > On 8/16/18, 6:51 AM, "dev on behalf of Luca Boccassi" <dev-boun
> ces@d
>     > pdk.org on behalf of bluca@debian.org> wrote:
>     > 
>     >     The vmxnet3 driver can't call back into dev_close(), and
> possibly
>     >     dev_stop(), in dev_uninit().  When dev_uninit() is called,
>     > anything
>     >     that those routines would want to clean up has already been
>     > released.
>     >     Further, for complete cleanup, it is necessary to release
> any of
>     > the
>     >     queue resources during dev_close().
>     >     This allows a vmxnet3 device to be hot-unplugged without
> leaking
>     >     queues.
>     >     
>     >     Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode
>     > driver implementation")
>     >     Cc: stable@dpdk.org
>     >     
>     >     Signed-off-by: Brian Russell <brussell@brocade.com>
>     >     Signed-off-by: Luca Boccassi <bluca@debian.org>
>     >     ---
>     >      drivers/net/vmxnet3/vmxnet3_ethdev.c | 36
> ++++++++++++++++++++
>     > --------
>     >      1 file changed, 26 insertions(+), 10 deletions(-)
>     >     
>     >     diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     > b/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     >     index 2613cd1358..b5d4be5e24 100644
>     >     --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     >     +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     >     @@ -348,16 +348,11 @@ eth_vmxnet3_dev_init(struct
> rte_eth_dev
>     > *eth_dev)
>     >      static int
>     >      eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
>     >      {
>     >     -	struct vmxnet3_hw *hw = eth_dev->data-
> >dev_private;
>     >     -
>     >      	PMD_INIT_FUNC_TRACE();
>     >      
>     >      	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
>     >      		return 0;
>     >      
>     >     -	if (hw->adapter_stopped == 0)
>     >     -		vmxnet3_dev_close(eth_dev);
>     >     -
>     >      	eth_dev->dev_ops = NULL;
>     >      	eth_dev->rx_pkt_burst = NULL;
>     >      	eth_dev->tx_pkt_burst = NULL;
>     >     @@ -803,7 +798,7 @@ vmxnet3_dev_stop(struct rte_eth_dev
> *dev)
>     >      	PMD_INIT_FUNC_TRACE();
>     >      
>     >      	if (hw->adapter_stopped == 1) {
>     >     -		PMD_INIT_LOG(DEBUG, "Device already
> closed.");
>     >     +		PMD_INIT_LOG(DEBUG, "Device already
> stopped.");
>     >      		return;
>     >      	}
>     >      
>     >     @@ -827,7 +822,6 @@ vmxnet3_dev_stop(struct rte_eth_dev
> *dev)
>     >      	/* reset the device */
>     >      	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD,
>     > VMXNET3_CMD_RESET_DEV);
>     >      	PMD_INIT_LOG(DEBUG, "Device reset.");
>     >     -	hw->adapter_stopped = 0;
>     >      
>     >      	vmxnet3_dev_clear_queues(dev);
>     >      
>     >     @@ -837,6 +831,30 @@ vmxnet3_dev_stop(struct rte_eth_dev
> *dev)
>     >      	link.link_speed = ETH_SPEED_NUM_10G;
>     >      	link.link_autoneg = ETH_LINK_FIXED;
>     >      	rte_eth_linkstatus_set(dev, &link);
>     >     +
>     >     +	hw->adapter_stopped = 1;
>     >     +}
>     >     +
>     >     +static void
>     >     +vmxnet3_free_queues(struct rte_eth_dev *dev)
>     >     +{
>     >     +	int i;
>     >     +
>     >     +	PMD_INIT_FUNC_TRACE();
>     >     +
>     >     +	for (i = 0; i < dev->data->nb_rx_queues; i++) {
>     >     +		void *rxq = dev->data->rx_queues[i];
>     >     +
>     >     +		vmxnet3_dev_rx_queue_release(rxq);
>     >     +	}
>     >     +	dev->data->nb_rx_queues = 0;
>     >     +
>     >     +	for (i = 0; i < dev->data->nb_tx_queues; i++) {
>     >     +		void *txq = dev->data->tx_queues[i];
>     >     +
>     >     +		vmxnet3_dev_tx_queue_release(txq);
>     >     +	}
>     >     +	dev->data->nb_tx_queues = 0;
>     >      }
>     >      
>     >      /*
>     >     @@ -845,12 +863,10 @@ vmxnet3_dev_stop(struct rte_eth_dev
> *dev)
>     >      static void
>     >      vmxnet3_dev_close(struct rte_eth_dev *dev)
>     >      {
>     >     -	struct vmxnet3_hw *hw = dev->data->dev_private;
>     >     -
>     >      	PMD_INIT_FUNC_TRACE();
>     >      
>     >      	vmxnet3_dev_stop(dev);
>     >     -	hw->adapter_stopped = 1;
>     >     +	vmxnet3_free_queues(dev);
>     >      }
>     >      
>     >      static void
>     >     -- 
>     >     2.18.0
>     >     
>     >     
>     > 
>     
>     -- 
>     Kind regards,
>     Luca Boccassi
> 

-- 
Kind regards,
Luca Boccassi

Re: [dpdk-dev] [PATCH 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Louis Luo]

Hi Luca,

I'm fine with the queue free part, but just have concern about removing the check inside uninit function. If the application does follow the rules and keeping the check in uninit won't cause vmxnet3_dev_close() being called again (and if it won't cause trouble in case the application doesn't call close before calling uninit), I prefer keeping the check (and log some warning) in case any buggy application exists.

Thanks,
Louis

On 9/18/18, 11:29 AM, "Luca Boccassi" <bluca@debian.org> wrote:

    On Tue, 2018-09-18 at 18:14 +0000, Louis Luo wrote:
    > Hi Luca,
    > 
    > Thanks for pointing to the document! This "basic requirements" seems
    > to lay the burden on application developers to correctly follow the
    > hot-plug framework's rules, but there seems no mechanism to enforce
    > this procedure (correct me if I'm wrong). What if a buggy application
    > doesn't call stop/close before detaching? 
    
    Well DPDK in general does not have the simplest API to use, there's no
    denying that. That's because what it does is very much more complicated
    than the average library.
    So if an application ignores the development guides and does not follow
    the recommendation bad things will happen :-) But it will happen
    regardless of the PMD used. That's already the case.
    
    > In addition, in your commit description, you said " The vmxnet3
    > driver can't call back into dev_close(), and possibly dev_stop(), in
    > dev_uninit()." But actually in vmxnet3_dev_close(), we set hw-
    > >adapter_stopped = 1, and in eth_vmxnet3_dev_uninit() we call into
    > vmxnet3_dev_close() ONLY when hw->adapter_stopped == 0. So if the
    > application does meet the hot-plug framework requirement and calls
    > dev_close before calling uninit, eth_vmxnet3_dev_uninit() should not
    > call into vmxnet3_dev_close() again, right? If so, why bother
    > removing this check? 
    > 
    > Or let me ask this way. If a buggy application DOES NOT call
    > dev_close before calling eth_vmxnet3_dev_uninit(), would calling
    > vmxnet3_dev_close() inside eth_vmxnet3_dev_uninit() cause any
    > trouble? And if an application DOES call dev_close before calling
    > eth_vmxnet3_dev_uninit(), have you ever seen vmxnet3_dev_close()
    > being called again and trigger crashes like double-free or something
    > else? If yes, then we need to investigate.
    > 
    > Thanks
    > Louis
    
    The problem is that there are many PMDs, so the guidelines have to be
    followed - so stop and close have to be called anyway before detach.
    Otherwise running with other PMDs will break the application. So not
    calling close is not really an option for an application.
    
    But the main issue here is the leaking of the queues, which this patch
    fixes. By re-arranging the stop/close/uninit like this, queues can be
    correctly freed and thus we can hotplug/unplug devices without leaking
    massive amounts of memory.
    
    My colleague Brian, who wrote the patch and I CC'ed, might have more
    information if you need it.
    
    > On 9/18/18, 6:15 AM, "Luca Boccassi" <bluca@debian.org> wrote:
    > 
    >     Hi,
    >     
    >     The application must already stop and close before detaching
    > (which
    >     will call uninit). Quoting from the documentation:
    >     
    >     "*  Before detaching, they must be stopped and closed.
    >     
    >         DPDK applications must call "rte_eth_dev_stop()" and
    >         "rte_eth_dev_close()" APIs before detaching ports. These
    > functions will
    >         start finalization sequence of the PMDs."
    >     
    >     https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fd
    > oc.dpdk.org%2Fguides%2Fprog_guide%2Fport_hotplug_framework.html&amp;d
    > ata=02%7C01%7Cllouis%40vmware.com%7C3d87a5482cd046679d7608d61d68bf9a%
    > 7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C1%7C0%7C636728733078700911&amp;s
    > data=qBx7zyOJhTmVH0c2ZEBohmIHL6PkYwB6XPaw2epgS0E%3D&amp;reserved=0
    >     
    >     On Mon, 2018-09-17 at 19:06 +0000, Louis Luo wrote:
    >     > Hi Luca,
    >     > 
    >     > When eth_vmxnet3_dev_uninit() is called, is it guaranteed that
    >     > vmxnet3_dev_close/ vmxnet3_dev_stop must have been called? I'm
    > not
    >     > familiar with the hot-plug procedure, so just wonder if there
    > is any
    >     > chance that eth_vmxnet3_dev_uninit() is called without calling
    >     > vmxnet3_dev_close/ vmxnet3_dev_stop.
    >     > 
    >     > Thanks,
    >     > Louis
    >     > 
    >     > On 8/16/18, 6:51 AM, "dev on behalf of Luca Boccassi" <dev-boun
    > ces@d
    >     > pdk.org on behalf of bluca@debian.org> wrote:
    >     > 
    >     >     The vmxnet3 driver can't call back into dev_close(), and
    > possibly
    >     >     dev_stop(), in dev_uninit().  When dev_uninit() is called,
    >     > anything
    >     >     that those routines would want to clean up has already been
    >     > released.
    >     >     Further, for complete cleanup, it is necessary to release
    > any of
    >     > the
    >     >     queue resources during dev_close().
    >     >     This allows a vmxnet3 device to be hot-unplugged without
    > leaking
    >     >     queues.
    >     >     
    >     >     Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode
    >     > driver implementation")
    >     >     Cc: stable@dpdk.org
    >     >     
    >     >     Signed-off-by: Brian Russell <brussell@brocade.com>
    >     >     Signed-off-by: Luca Boccassi <bluca@debian.org>
    >     >     ---
    >     >      drivers/net/vmxnet3/vmxnet3_ethdev.c | 36
    > ++++++++++++++++++++
    >     > --------
    >     >      1 file changed, 26 insertions(+), 10 deletions(-)
    >     >     
    >     >     diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
    >     > b/drivers/net/vmxnet3/vmxnet3_ethdev.c
    >     >     index 2613cd1358..b5d4be5e24 100644
    >     >     --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
    >     >     +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
    >     >     @@ -348,16 +348,11 @@ eth_vmxnet3_dev_init(struct
    > rte_eth_dev
    >     > *eth_dev)
    >     >      static int
    >     >      eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
    >     >      {
    >     >     -	struct vmxnet3_hw *hw = eth_dev->data-
    > >dev_private;
    >     >     -
    >     >      	PMD_INIT_FUNC_TRACE();
    >     >      
    >     >      	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
    >     >      		return 0;
    >     >      
    >     >     -	if (hw->adapter_stopped == 0)
    >     >     -		vmxnet3_dev_close(eth_dev);
    >     >     -
    >     >      	eth_dev->dev_ops = NULL;
    >     >      	eth_dev->rx_pkt_burst = NULL;
    >     >      	eth_dev->tx_pkt_burst = NULL;
    >     >     @@ -803,7 +798,7 @@ vmxnet3_dev_stop(struct rte_eth_dev
    > *dev)
    >     >      	PMD_INIT_FUNC_TRACE();
    >     >      
    >     >      	if (hw->adapter_stopped == 1) {
    >     >     -		PMD_INIT_LOG(DEBUG, "Device already
    > closed.");
    >     >     +		PMD_INIT_LOG(DEBUG, "Device already
    > stopped.");
    >     >      		return;
    >     >      	}
    >     >      
    >     >     @@ -827,7 +822,6 @@ vmxnet3_dev_stop(struct rte_eth_dev
    > *dev)
    >     >      	/* reset the device */
    >     >      	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD,
    >     > VMXNET3_CMD_RESET_DEV);
    >     >      	PMD_INIT_LOG(DEBUG, "Device reset.");
    >     >     -	hw->adapter_stopped = 0;
    >     >      
    >     >      	vmxnet3_dev_clear_queues(dev);
    >     >      
    >     >     @@ -837,6 +831,30 @@ vmxnet3_dev_stop(struct rte_eth_dev
    > *dev)
    >     >      	link.link_speed = ETH_SPEED_NUM_10G;
    >     >      	link.link_autoneg = ETH_LINK_FIXED;
    >     >      	rte_eth_linkstatus_set(dev, &link);
    >     >     +
    >     >     +	hw->adapter_stopped = 1;
    >     >     +}
    >     >     +
    >     >     +static void
    >     >     +vmxnet3_free_queues(struct rte_eth_dev *dev)
    >     >     +{
    >     >     +	int i;
    >     >     +
    >     >     +	PMD_INIT_FUNC_TRACE();
    >     >     +
    >     >     +	for (i = 0; i < dev->data->nb_rx_queues; i++) {
    >     >     +		void *rxq = dev->data->rx_queues[i];
    >     >     +
    >     >     +		vmxnet3_dev_rx_queue_release(rxq);
    >     >     +	}
    >     >     +	dev->data->nb_rx_queues = 0;
    >     >     +
    >     >     +	for (i = 0; i < dev->data->nb_tx_queues; i++) {
    >     >     +		void *txq = dev->data->tx_queues[i];
    >     >     +
    >     >     +		vmxnet3_dev_tx_queue_release(txq);
    >     >     +	}
    >     >     +	dev->data->nb_tx_queues = 0;
    >     >      }
    >     >      
    >     >      /*
    >     >     @@ -845,12 +863,10 @@ vmxnet3_dev_stop(struct rte_eth_dev
    > *dev)
    >     >      static void
    >     >      vmxnet3_dev_close(struct rte_eth_dev *dev)
    >     >      {
    >     >     -	struct vmxnet3_hw *hw = dev->data->dev_private;
    >     >     -
    >     >      	PMD_INIT_FUNC_TRACE();
    >     >      
    >     >      	vmxnet3_dev_stop(dev);
    >     >     -	hw->adapter_stopped = 1;
    >     >     +	vmxnet3_free_queues(dev);
    >     >      }
    >     >      
    >     >      static void
    >     >     -- 
    >     >     2.18.0
    >     >     
    >     >     
    >     > 
    >     
    >     -- 
    >     Kind regards,
    >     Luca Boccassi
    > 
    
    -- 
    Kind regards,
    Luca Boccassi

[dpdk-dev] [PATCH v2 1/3] net/virtio: register/unregister intr handler on start/stop

[Luca Boccassi]

Register and unregister the virtio interrupt handler when the device is
started and stopped. This allows a virtio device to be hotplugged or
unplugged.

Fixes: c1f86306a026 ("virtio: add new driver")
Cc: stable@dpdk.org

Signed-off-by: Brian Russell <brussell@brocade.com>
Signed-off-by: Luca Boccassi <bluca@debian.org>
---
 drivers/net/virtio/virtio_ethdev.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index b81df0a99f..adc6a30a32 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1679,11 +1679,6 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 	if (ret < 0)
 		goto out;
 
-	/* Setup interrupt callback  */
-	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
-		rte_intr_callback_register(eth_dev->intr_handle,
-			virtio_interrupt_handler, eth_dev);
-
 	return 0;
 
 out:
@@ -1709,11 +1704,6 @@ eth_virtio_dev_uninit(struct rte_eth_dev *eth_dev)
 	rte_free(eth_dev->data->mac_addrs);
 	eth_dev->data->mac_addrs = NULL;
 
-	/* reset interrupt callback  */
-	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
-		rte_intr_callback_unregister(eth_dev->intr_handle,
-						virtio_interrupt_handler,
-						eth_dev);
 	if (eth_dev->device)
 		rte_pci_unmap_device(RTE_ETH_DEV_TO_PCI(eth_dev));
 
@@ -1972,6 +1962,12 @@ virtio_dev_start(struct rte_eth_dev *dev)
 	    dev->data->dev_conf.intr_conf.rxq) {
 		virtio_intr_disable(dev);
 
+		/* Setup interrupt callback  */
+		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
+			rte_intr_callback_register(dev->intr_handle,
+						   virtio_interrupt_handler,
+						   dev);
+
 		if (virtio_intr_enable(dev) < 0) {
 			PMD_DRV_LOG(ERR, "interrupt enable failed");
 			return -EIO;
@@ -2081,9 +2077,17 @@ virtio_dev_stop(struct rte_eth_dev *dev)
 	PMD_INIT_LOG(DEBUG, "stop");
 
 	rte_spinlock_lock(&hw->state_lock);
-	if (intr_conf->lsc || intr_conf->rxq)
+	if (intr_conf->lsc || intr_conf->rxq) {
 		virtio_intr_disable(dev);
 
+		/* Reset interrupt callback  */
+		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC) {
+			rte_intr_callback_unregister(dev->intr_handle,
+						     virtio_interrupt_handler,
+						     dev);
+		}
+	}
+
 	hw->started = 0;
 	memset(&link, 0, sizeof(link));
 	rte_eth_linkstatus_set(dev, &link);
-- 
2.18.0

[dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

The vmxnet3 driver can't call back into dev_close(), and possibly
dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
that those routines would want to clean up has already been released.
Further, for complete cleanup, it is necessary to release any of the
queue resources during dev_close().
This allows a vmxnet3 device to be hot-unplugged without leaking
queues.

Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver implementation")
Cc: stable@dpdk.org

Signed-off-by: Brian Russell <brussell@brocade.com>
Signed-off-by: Luca Boccassi <bluca@debian.org>
---
v2: add back extra close() call in uninit() for buggy applications as
    requested by the reviewers, and add debug log noting the issue

 drivers/net/vmxnet3/vmxnet3_ethdev.c | 35 +++++++++++++++++++++++-----
 1 file changed, 29 insertions(+), 6 deletions(-)

diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c b/drivers/net/vmxnet3/vmxnet3_ethdev.c
index f1596ab19d..98e5d01890 100644
--- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
+++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
@@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
 	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
 		return 0;
 
-	if (hw->adapter_stopped == 0)
+	if (hw->adapter_stopped == 0) {
+		PMD_INIT_LOG(DEBUG, "Device has not been closed.");
 		vmxnet3_dev_close(eth_dev);
+	}
 
 	eth_dev->dev_ops = NULL;
 	eth_dev->rx_pkt_burst = NULL;
@@ -802,7 +804,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	PMD_INIT_FUNC_TRACE();
 
 	if (hw->adapter_stopped == 1) {
-		PMD_INIT_LOG(DEBUG, "Device already closed.");
+		PMD_INIT_LOG(DEBUG, "Device already stopped.");
 		return;
 	}
 
@@ -826,7 +828,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	/* reset the device */
 	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD, VMXNET3_CMD_RESET_DEV);
 	PMD_INIT_LOG(DEBUG, "Device reset.");
-	hw->adapter_stopped = 0;
 
 	vmxnet3_dev_clear_queues(dev);
 
@@ -836,6 +837,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	link.link_speed = ETH_SPEED_NUM_10G;
 	link.link_autoneg = ETH_LINK_FIXED;
 	rte_eth_linkstatus_set(dev, &link);
+
+	hw->adapter_stopped = 1;
+}
+
+static void
+vmxnet3_free_queues(struct rte_eth_dev *dev)
+{
+	int i;
+
+	PMD_INIT_FUNC_TRACE();
+
+	for (i = 0; i < dev->data->nb_rx_queues; i++) {
+		void *rxq = dev->data->rx_queues[i];
+
+		vmxnet3_dev_rx_queue_release(rxq);
+	}
+	dev->data->nb_rx_queues = 0;
+
+	for (i = 0; i < dev->data->nb_tx_queues; i++) {
+		void *txq = dev->data->tx_queues[i];
+
+		vmxnet3_dev_tx_queue_release(txq);
+	}
+	dev->data->nb_tx_queues = 0;
 }
 
 /*
@@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 static void
 vmxnet3_dev_close(struct rte_eth_dev *dev)
 {
-	struct vmxnet3_hw *hw = dev->data->dev_private;
-
 	PMD_INIT_FUNC_TRACE();
 
 	vmxnet3_dev_stop(dev);
-	hw->adapter_stopped = 1;
+	vmxnet3_free_queues(dev);
 }
 
 static void
-- 
2.18.0

[dpdk-dev] [PATCH v2 3/3] eal/linux: handle uio read failure in interrupt handler

[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: 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

Re: [dpdk-dev] [PATCH 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

Ok, I've added it back with a debug log in v2.

On Tue, 2018-09-18 at 18:48 +0000, Louis Luo wrote:
> Hi Luca,
> 
> I'm fine with the queue free part, but just have concern about
> removing the check inside uninit function. If the application does
> follow the rules and keeping the check in uninit won't cause
> vmxnet3_dev_close() being called again (and if it won't cause trouble
> in case the application doesn't call close before calling uninit), I
> prefer keeping the check (and log some warning) in case any buggy
> application exists.
> 
> Thanks,
> Louis
> 
> On 9/18/18, 11:29 AM, "Luca Boccassi" <bluca@debian.org> wrote:
> 
>     On Tue, 2018-09-18 at 18:14 +0000, Louis Luo wrote:
>     > Hi Luca,
>     > 
>     > Thanks for pointing to the document! This "basic requirements"
> seems
>     > to lay the burden on application developers to correctly follow
> the
>     > hot-plug framework's rules, but there seems no mechanism to
> enforce
>     > this procedure (correct me if I'm wrong). What if a buggy
> application
>     > doesn't call stop/close before detaching? 
>     
>     Well DPDK in general does not have the simplest API to use,
> there's no
>     denying that. That's because what it does is very much more
> complicated
>     than the average library.
>     So if an application ignores the development guides and does not
> follow
>     the recommendation bad things will happen :-) But it will happen
>     regardless of the PMD used. That's already the case.
>     
>     > In addition, in your commit description, you said " The vmxnet3
>     > driver can't call back into dev_close(), and possibly
> dev_stop(), in
>     > dev_uninit()." But actually in vmxnet3_dev_close(), we set hw-
>     > >adapter_stopped = 1, and in eth_vmxnet3_dev_uninit() we call
> into
>     > vmxnet3_dev_close() ONLY when hw->adapter_stopped == 0. So if
> the
>     > application does meet the hot-plug framework requirement and
> calls
>     > dev_close before calling uninit, eth_vmxnet3_dev_uninit()
> should not
>     > call into vmxnet3_dev_close() again, right? If so, why bother
>     > removing this check? 
>     > 
>     > Or let me ask this way. If a buggy application DOES NOT call
>     > dev_close before calling eth_vmxnet3_dev_uninit(), would
> calling
>     > vmxnet3_dev_close() inside eth_vmxnet3_dev_uninit() cause any
>     > trouble? And if an application DOES call dev_close before
> calling
>     > eth_vmxnet3_dev_uninit(), have you ever seen
> vmxnet3_dev_close()
>     > being called again and trigger crashes like double-free or
> something
>     > else? If yes, then we need to investigate.
>     > 
>     > Thanks
>     > Louis
>     
>     The problem is that there are many PMDs, so the guidelines have
> to be
>     followed - so stop and close have to be called anyway before
> detach.
>     Otherwise running with other PMDs will break the application. So
> not
>     calling close is not really an option for an application.
>     
>     But the main issue here is the leaking of the queues, which this
> patch
>     fixes. By re-arranging the stop/close/uninit like this, queues
> can be
>     correctly freed and thus we can hotplug/unplug devices without
> leaking
>     massive amounts of memory.
>     
>     My colleague Brian, who wrote the patch and I CC'ed, might have
> more
>     information if you need it.
>     
>     > On 9/18/18, 6:15 AM, "Luca Boccassi" <bluca@debian.org> wrote:
>     > 
>     >     Hi,
>     >     
>     >     The application must already stop and close before
> detaching
>     > (which
>     >     will call uninit). Quoting from the documentation:
>     >     
>     >     "*  Before detaching, they must be stopped and closed.
>     >     
>     >         DPDK applications must call "rte_eth_dev_stop()" and
>     >         "rte_eth_dev_close()" APIs before detaching ports.
> These
>     > functions will
>     >         start finalization sequence of the PMDs."
>     >     
>     >     https://na01.safelinks.protection.outlook.com/?url=http%3A%
> 2F%2Fd
>     >
> oc.dpdk.org%2Fguides%2Fprog_guide%2Fport_hotplug_framework.html&amp;d
>     >
> ata=02%7C01%7Cllouis%40vmware.com%7C3d87a5482cd046679d7608d61d68bf9a%
>     >
> 7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C1%7C0%7C636728733078700911&amp;s
>     >
> data=qBx7zyOJhTmVH0c2ZEBohmIHL6PkYwB6XPaw2epgS0E%3D&amp;reserved=0
>     >     
>     >     On Mon, 2018-09-17 at 19:06 +0000, Louis Luo wrote:
>     >     > Hi Luca,
>     >     > 
>     >     > When eth_vmxnet3_dev_uninit() is called, is it guaranteed
> that
>     >     > vmxnet3_dev_close/ vmxnet3_dev_stop must have been
> called? I'm
>     > not
>     >     > familiar with the hot-plug procedure, so just wonder if
> there
>     > is any
>     >     > chance that eth_vmxnet3_dev_uninit() is called without
> calling
>     >     > vmxnet3_dev_close/ vmxnet3_dev_stop.
>     >     > 
>     >     > Thanks,
>     >     > Louis
>     >     > 
>     >     > On 8/16/18, 6:51 AM, "dev on behalf of Luca Boccassi"
> <dev-boun
>     > ces@d
>     >     > pdk.org on behalf of bluca@debian.org> wrote:
>     >     > 
>     >     >     The vmxnet3 driver can't call back into dev_close(),
> and
>     > possibly
>     >     >     dev_stop(), in dev_uninit().  When dev_uninit() is
> called,
>     >     > anything
>     >     >     that those routines would want to clean up has
> already been
>     >     > released.
>     >     >     Further, for complete cleanup, it is necessary to
> release
>     > any of
>     >     > the
>     >     >     queue resources during dev_close().
>     >     >     This allows a vmxnet3 device to be hot-unplugged
> without
>     > leaking
>     >     >     queues.
>     >     >     
>     >     >     Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3
> poll mode
>     >     > driver implementation")
>     >     >     Cc: stable@dpdk.org
>     >     >     
>     >     >     Signed-off-by: Brian Russell <brussell@brocade.com>
>     >     >     Signed-off-by: Luca Boccassi <bluca@debian.org>
>     >     >     ---
>     >     >      drivers/net/vmxnet3/vmxnet3_ethdev.c | 36
>     > ++++++++++++++++++++
>     >     > --------
>     >     >      1 file changed, 26 insertions(+), 10 deletions(-)
>     >     >     
>     >     >     diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     >     > b/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     >     >     index 2613cd1358..b5d4be5e24 100644
>     >     >     --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     >     >     +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
>     >     >     @@ -348,16 +348,11 @@ eth_vmxnet3_dev_init(struct
>     > rte_eth_dev
>     >     > *eth_dev)
>     >     >      static int
>     >     >      eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
>     >     >      {
>     >     >     -	struct vmxnet3_hw *hw = eth_dev->data-
>     > >dev_private;
>     >     >     -
>     >     >      	PMD_INIT_FUNC_TRACE();
>     >     >      
>     >     >      	if (rte_eal_process_type() !=
> RTE_PROC_PRIMARY)
>     >     >      		return 0;
>     >     >      
>     >     >     -	if (hw->adapter_stopped == 0)
>     >     >     -		vmxnet3_dev_close(eth_dev);
>     >     >     -
>     >     >      	eth_dev->dev_ops = NULL;
>     >     >      	eth_dev->rx_pkt_burst = NULL;
>     >     >      	eth_dev->tx_pkt_burst = NULL;
>     >     >     @@ -803,7 +798,7 @@ vmxnet3_dev_stop(struct
> rte_eth_dev
>     > *dev)
>     >     >      	PMD_INIT_FUNC_TRACE();
>     >     >      
>     >     >      	if (hw->adapter_stopped == 1) {
>     >     >     -		PMD_INIT_LOG(DEBUG, "Device already
>     > closed.");
>     >     >     +		PMD_INIT_LOG(DEBUG, "Device already
>     > stopped.");
>     >     >      		return;
>     >     >      	}
>     >     >      
>     >     >     @@ -827,7 +822,6 @@ vmxnet3_dev_stop(struct
> rte_eth_dev
>     > *dev)
>     >     >      	/* reset the device */
>     >     >      	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD,
>     >     > VMXNET3_CMD_RESET_DEV);
>     >     >      	PMD_INIT_LOG(DEBUG, "Device reset.");
>     >     >     -	hw->adapter_stopped = 0;
>     >     >      
>     >     >      	vmxnet3_dev_clear_queues(dev);
>     >     >      
>     >     >     @@ -837,6 +831,30 @@ vmxnet3_dev_stop(struct
> rte_eth_dev
>     > *dev)
>     >     >      	link.link_speed = ETH_SPEED_NUM_10G;
>     >     >      	link.link_autoneg = ETH_LINK_FIXED;
>     >     >      	rte_eth_linkstatus_set(dev, &link);
>     >     >     +
>     >     >     +	hw->adapter_stopped = 1;
>     >     >     +}
>     >     >     +
>     >     >     +static void
>     >     >     +vmxnet3_free_queues(struct rte_eth_dev *dev)
>     >     >     +{
>     >     >     +	int i;
>     >     >     +
>     >     >     +	PMD_INIT_FUNC_TRACE();
>     >     >     +
>     >     >     +	for (i = 0; i < dev->data->nb_rx_queues;
> i++) {
>     >     >     +		void *rxq = dev->data->rx_queues[i];
>     >     >     +
>     >     >     +		vmxnet3_dev_rx_queue_release(rxq);
>     >     >     +	}
>     >     >     +	dev->data->nb_rx_queues = 0;
>     >     >     +
>     >     >     +	for (i = 0; i < dev->data->nb_tx_queues;
> i++) {
>     >     >     +		void *txq = dev->data->tx_queues[i];
>     >     >     +
>     >     >     +		vmxnet3_dev_tx_queue_release(txq);
>     >     >     +	}
>     >     >     +	dev->data->nb_tx_queues = 0;
>     >     >      }
>     >     >      
>     >     >      /*
>     >     >     @@ -845,12 +863,10 @@ vmxnet3_dev_stop(struct
> rte_eth_dev
>     > *dev)
>     >     >      static void
>     >     >      vmxnet3_dev_close(struct rte_eth_dev *dev)
>     >     >      {
>     >     >     -	struct vmxnet3_hw *hw = dev->data-
> >dev_private;
>     >     >     -
>     >     >      	PMD_INIT_FUNC_TRACE();
>     >     >      
>     >     >      	vmxnet3_dev_stop(dev);
>     >     >     -	hw->adapter_stopped = 1;
>     >     >     +	vmxnet3_free_queues(dev);
>     >     >      }
>     >     >      
>     >     >      static void
>     >     >     -- 
>     >     >     2.18.0
>     >     >     
>     >     >     
>     >     > 
>     >     
>     >     -- 
>     >     Kind regards,
>     >     Luca Boccassi
>     > 
>     
>     -- 
>     Kind regards,
>     Luca Boccassi
> 

-- 
Kind regards,
Luca Boccassi

Re: [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Chas Williams]

On Wed, Sep 19, 2018 at 8:58 AM Luca Boccassi <bluca@debian.org> wrote:
>
> The vmxnet3 driver can't call back into dev_close(), and possibly
> dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
> that those routines would want to clean up has already been released.
> Further, for complete cleanup, it is necessary to release any of the
> queue resources during dev_close().
> This allows a vmxnet3 device to be hot-unplugged without leaking
> queues.
>
> Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver implementation")
> Cc: stable@dpdk.org
>
> Signed-off-by: Brian Russell <brussell@brocade.com>
> Signed-off-by: Luca Boccassi <bluca@debian.org>
> ---
> v2: add back extra close() call in uninit() for buggy applications as
>     requested by the reviewers, and add debug log noting the issue
>
>  drivers/net/vmxnet3/vmxnet3_ethdev.c | 35 +++++++++++++++++++++++-----
>  1 file changed, 29 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> index f1596ab19d..98e5d01890 100644
> --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> @@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
>         if (rte_eal_process_type() != RTE_PROC_PRIMARY)
>                 return 0;

This should probably be EPERM as well.  Out of scope though.

>
> -       if (hw->adapter_stopped == 0)
> +       if (hw->adapter_stopped == 0) {
> +               PMD_INIT_LOG(DEBUG, "Device has not been closed.");
>                 vmxnet3_dev_close(eth_dev);

This just seems wrong.  You have called uninit() will the driver is
still busy.  Instead of "fixing" the state of the driver, return EBUSY
here.

> +       }
>
>         eth_dev->dev_ops = NULL;
>         eth_dev->rx_pkt_burst = NULL;
> @@ -802,7 +804,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>         PMD_INIT_FUNC_TRACE();
>
>         if (hw->adapter_stopped == 1) {
> -               PMD_INIT_LOG(DEBUG, "Device already closed.");
> +               PMD_INIT_LOG(DEBUG, "Device already stopped.");
>                 return;
>         }
>
> @@ -826,7 +828,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>         /* reset the device */
>         VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD, VMXNET3_CMD_RESET_DEV);
>         PMD_INIT_LOG(DEBUG, "Device reset.");
> -       hw->adapter_stopped = 0;
>
>         vmxnet3_dev_clear_queues(dev);
>
> @@ -836,6 +837,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>         link.link_speed = ETH_SPEED_NUM_10G;
>         link.link_autoneg = ETH_LINK_FIXED;
>         rte_eth_linkstatus_set(dev, &link);
> +
> +       hw->adapter_stopped = 1;
> +}
> +
> +static void
> +vmxnet3_free_queues(struct rte_eth_dev *dev)
> +{
> +       int i;
> +
> +       PMD_INIT_FUNC_TRACE();
> +
> +       for (i = 0; i < dev->data->nb_rx_queues; i++) {
> +               void *rxq = dev->data->rx_queues[i];
> +
> +               vmxnet3_dev_rx_queue_release(rxq);
> +       }
> +       dev->data->nb_rx_queues = 0;
> +
> +       for (i = 0; i < dev->data->nb_tx_queues; i++) {
> +               void *txq = dev->data->tx_queues[i];
> +
> +               vmxnet3_dev_tx_queue_release(txq);
> +       }
> +       dev->data->nb_tx_queues = 0;
>  }
>
>  /*
> @@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>  static void
>  vmxnet3_dev_close(struct rte_eth_dev *dev)
>  {
> -       struct vmxnet3_hw *hw = dev->data->dev_private;
> -
>         PMD_INIT_FUNC_TRACE();
>
>         vmxnet3_dev_stop(dev);
> -       hw->adapter_stopped = 1;
> +       vmxnet3_free_queues(dev);
>  }
>
>  static void
> --
> 2.18.0
>

Re: [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

On Wed, 2018-09-19 at 11:47 -0400, Chas Williams wrote:
> On Wed, Sep 19, 2018 at 8:58 AM Luca Boccassi <bluca@debian.org>
> wrote:
> > 
> > The vmxnet3 driver can't call back into dev_close(), and possibly
> > dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
> > that those routines would want to clean up has already been
> > released.
> > Further, for complete cleanup, it is necessary to release any of
> > the
> > queue resources during dev_close().
> > This allows a vmxnet3 device to be hot-unplugged without leaking
> > queues.
> > 
> > Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver
> > implementation")
> > Cc: stable@dpdk.org
> > 
> > Signed-off-by: Brian Russell <brussell@brocade.com>
> > Signed-off-by: Luca Boccassi <bluca@debian.org>
> > ---
> > v2: add back extra close() call in uninit() for buggy applications
> > as
> >     requested by the reviewers, and add debug log noting the issue
> > 
> >  drivers/net/vmxnet3/vmxnet3_ethdev.c | 35 +++++++++++++++++++++++-
> > ----
> >  1 file changed, 29 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > index f1596ab19d..98e5d01890 100644
> > --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > @@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev
> > *eth_dev)
> >         if (rte_eal_process_type() != RTE_PROC_PRIMARY)
> >                 return 0;
> 
> This should probably be EPERM as well.  Out of scope though.
> 
> > 
> > -       if (hw->adapter_stopped == 0)
> > +       if (hw->adapter_stopped == 0) {
> > +               PMD_INIT_LOG(DEBUG, "Device has not been closed.");
> >                 vmxnet3_dev_close(eth_dev);
> 
> This just seems wrong.  You have called uninit() will the driver is
> still busy.  Instead of "fixing" the state of the driver, return
> EBUSY
> here.

At this point that's out of scope too - it doesn't affect the ability
to hotplug or not.
So please send another patch and discuss it further with Louis, who
requested to drop that change.

> > +       }
> > 
> >         eth_dev->dev_ops = NULL;
> >         eth_dev->rx_pkt_burst = NULL;
> > @@ -802,7 +804,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> >         PMD_INIT_FUNC_TRACE();
> > 
> >         if (hw->adapter_stopped == 1) {
> > -               PMD_INIT_LOG(DEBUG, "Device already closed.");
> > +               PMD_INIT_LOG(DEBUG, "Device already stopped.");
> >                 return;
> >         }
> > 
> > @@ -826,7 +828,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> >         /* reset the device */
> >         VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD,
> > VMXNET3_CMD_RESET_DEV);
> >         PMD_INIT_LOG(DEBUG, "Device reset.");
> > -       hw->adapter_stopped = 0;
> > 
> >         vmxnet3_dev_clear_queues(dev);
> > 
> > @@ -836,6 +837,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> >         link.link_speed = ETH_SPEED_NUM_10G;
> >         link.link_autoneg = ETH_LINK_FIXED;
> >         rte_eth_linkstatus_set(dev, &link);
> > +
> > +       hw->adapter_stopped = 1;
> > +}
> > +
> > +static void
> > +vmxnet3_free_queues(struct rte_eth_dev *dev)
> > +{
> > +       int i;
> > +
> > +       PMD_INIT_FUNC_TRACE();
> > +
> > +       for (i = 0; i < dev->data->nb_rx_queues; i++) {
> > +               void *rxq = dev->data->rx_queues[i];
> > +
> > +               vmxnet3_dev_rx_queue_release(rxq);
> > +       }
> > +       dev->data->nb_rx_queues = 0;
> > +
> > +       for (i = 0; i < dev->data->nb_tx_queues; i++) {
> > +               void *txq = dev->data->tx_queues[i];
> > +
> > +               vmxnet3_dev_tx_queue_release(txq);
> > +       }
> > +       dev->data->nb_tx_queues = 0;
> >  }
> > 
> >  /*
> > @@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> >  static void
> >  vmxnet3_dev_close(struct rte_eth_dev *dev)
> >  {
> > -       struct vmxnet3_hw *hw = dev->data->dev_private;
> > -
> >         PMD_INIT_FUNC_TRACE();
> > 
> >         vmxnet3_dev_stop(dev);
> > -       hw->adapter_stopped = 1;
> > +       vmxnet3_free_queues(dev);
> >  }
> > 
> >  static void
> > --
> > 2.18.0
> > 

-- 
Kind regards,
Luca Boccassi

Re: [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

On Wed, 2018-09-19 at 13:57 +0100, Luca Boccassi wrote:
> The vmxnet3 driver can't call back into dev_close(), and possibly
> dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
> that those routines would want to clean up has already been released.
> Further, for complete cleanup, it is necessary to release any of the
> queue resources during dev_close().
> This allows a vmxnet3 device to be hot-unplugged without leaking
> queues.
> 
> Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver
> implementation")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Brian Russell <brussell@brocade.com>
> Signed-off-by: Luca Boccassi <bluca@debian.org>
> ---
> v2: add back extra close() call in uninit() for buggy applications as
>     requested by the reviewers, and add debug log noting the issue
> 
>  drivers/net/vmxnet3/vmxnet3_ethdev.c | 35 +++++++++++++++++++++++---
> --
>  1 file changed, 29 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> index f1596ab19d..98e5d01890 100644
> --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> @@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev
> *eth_dev)
>  	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
>  		return 0;
>  
> -	if (hw->adapter_stopped == 0)
> +	if (hw->adapter_stopped == 0) {
> +		PMD_INIT_LOG(DEBUG, "Device has not been closed.");
>  		vmxnet3_dev_close(eth_dev);
> +	}
>  
>  	eth_dev->dev_ops = NULL;
>  	eth_dev->rx_pkt_burst = NULL;
> @@ -802,7 +804,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>  	PMD_INIT_FUNC_TRACE();
>  
>  	if (hw->adapter_stopped == 1) {
> -		PMD_INIT_LOG(DEBUG, "Device already closed.");
> +		PMD_INIT_LOG(DEBUG, "Device already stopped.");
>  		return;
>  	}
>  
> @@ -826,7 +828,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>  	/* reset the device */
>  	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD,
> VMXNET3_CMD_RESET_DEV);
>  	PMD_INIT_LOG(DEBUG, "Device reset.");
> -	hw->adapter_stopped = 0;
>  
>  	vmxnet3_dev_clear_queues(dev);
>  
> @@ -836,6 +837,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>  	link.link_speed = ETH_SPEED_NUM_10G;
>  	link.link_autoneg = ETH_LINK_FIXED;
>  	rte_eth_linkstatus_set(dev, &link);
> +
> +	hw->adapter_stopped = 1;
> +}
> +
> +static void
> +vmxnet3_free_queues(struct rte_eth_dev *dev)
> +{
> +	int i;
> +
> +	PMD_INIT_FUNC_TRACE();
> +
> +	for (i = 0; i < dev->data->nb_rx_queues; i++) {
> +		void *rxq = dev->data->rx_queues[i];
> +
> +		vmxnet3_dev_rx_queue_release(rxq);
> +	}
> +	dev->data->nb_rx_queues = 0;
> +
> +	for (i = 0; i < dev->data->nb_tx_queues; i++) {
> +		void *txq = dev->data->tx_queues[i];
> +
> +		vmxnet3_dev_tx_queue_release(txq);
> +	}
> +	dev->data->nb_tx_queues = 0;
>  }
>  
>  /*
> @@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
>  static void
>  vmxnet3_dev_close(struct rte_eth_dev *dev)
>  {
> -	struct vmxnet3_hw *hw = dev->data->dev_private;
> -
>  	PMD_INIT_FUNC_TRACE();
>  
>  	vmxnet3_dev_stop(dev);
> -	hw->adapter_stopped = 1;
> +	vmxnet3_free_queues(dev);
>  }
>  
>  static void

Hi Louis,

Are you happy with the diff as in v2 now for vmxnet3? Thanks

-- 
Kind regards,
Luca Boccassi

Re: [dpdk-dev] [PATCH v2 1/3] net/virtio: register/unregister intr handler on start/stop

[Luca Boccassi]

On Wed, 2018-09-19 at 13:57 +0100, Luca Boccassi wrote:
> Register and unregister the virtio interrupt handler when the device
> is
> started and stopped. This allows a virtio device to be hotplugged or
> unplugged.
> 
> Fixes: c1f86306a026 ("virtio: add new driver")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Brian Russell <brussell@brocade.com>
> Signed-off-by: Luca Boccassi <bluca@debian.org>
> ---
>  drivers/net/virtio/virtio_ethdev.c | 26 +++++++++++++++-----------
>  1 file changed, 15 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio_ethdev.c
> b/drivers/net/virtio/virtio_ethdev.c
> index b81df0a99f..adc6a30a32 100644
> --- a/drivers/net/virtio/virtio_ethdev.c
> +++ b/drivers/net/virtio/virtio_ethdev.c
> @@ -1679,11 +1679,6 @@ eth_virtio_dev_init(struct rte_eth_dev
> *eth_dev)
>  	if (ret < 0)
>  		goto out;
>  
> -	/* Setup interrupt callback  */
> -	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
> -		rte_intr_callback_register(eth_dev->intr_handle,
> -			virtio_interrupt_handler, eth_dev);
> -
>  	return 0;
>  
>  out:
> @@ -1709,11 +1704,6 @@ eth_virtio_dev_uninit(struct rte_eth_dev
> *eth_dev)
>  	rte_free(eth_dev->data->mac_addrs);
>  	eth_dev->data->mac_addrs = NULL;
>  
> -	/* reset interrupt callback  */
> -	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
> -		rte_intr_callback_unregister(eth_dev->intr_handle,
> -						virtio_interrupt_han
> dler,
> -						eth_dev);
>  	if (eth_dev->device)
>  		rte_pci_unmap_device(RTE_ETH_DEV_TO_PCI(eth_dev));
>  
> @@ -1972,6 +1962,12 @@ virtio_dev_start(struct rte_eth_dev *dev)
>  	    dev->data->dev_conf.intr_conf.rxq) {
>  		virtio_intr_disable(dev);
>  
> +		/* Setup interrupt callback  */
> +		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
> +			rte_intr_callback_register(dev->intr_handle,
> +						   virtio_interrupt_
> handler,
> +						   dev);
> +
>  		if (virtio_intr_enable(dev) < 0) {
>  			PMD_DRV_LOG(ERR, "interrupt enable failed");
>  			return -EIO;
> @@ -2081,9 +2077,17 @@ virtio_dev_stop(struct rte_eth_dev *dev)
>  	PMD_INIT_LOG(DEBUG, "stop");
>  
>  	rte_spinlock_lock(&hw->state_lock);
> -	if (intr_conf->lsc || intr_conf->rxq)
> +	if (intr_conf->lsc || intr_conf->rxq) {
>  		virtio_intr_disable(dev);
>  
> +		/* Reset interrupt callback  */
> +		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC) {
> +			rte_intr_callback_unregister(dev-
> >intr_handle,
> +						     virtio_interrup
> t_handler,
> +						     dev);
> +		}
> +	}
> +
>  	hw->started = 0;
>  	memset(&link, 0, sizeof(link));
>  	rte_eth_linkstatus_set(dev, &link);

Hi, any chance the virtio and eal patches in this series could get a
review? Thanks!

-- 
Kind regards,
Luca Boccassi

Re: [dpdk-dev] [PATCH v2 1/3] net/virtio: register/unregister intr handler on start/stop

[Maxime Coquelin]

On 09/27/2018 10:40 AM, Luca Boccassi wrote:
> On Wed, 2018-09-19 at 13:57 +0100, Luca Boccassi wrote:
>> Register and unregister the virtio interrupt handler when the device
>> is
>> started and stopped. This allows a virtio device to be hotplugged or
>> unplugged.
>>
>> Fixes: c1f86306a026 ("virtio: add new driver")
>> Cc: stable@dpdk.org
>>
>> Signed-off-by: Brian Russell <brussell@brocade.com>
>> Signed-off-by: Luca Boccassi <bluca@debian.org>
>> ---
>>   drivers/net/virtio/virtio_ethdev.c | 26 +++++++++++++++-----------
>>   1 file changed, 15 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/net/virtio/virtio_ethdev.c
>> b/drivers/net/virtio/virtio_ethdev.c
>> index b81df0a99f..adc6a30a32 100644
>> --- a/drivers/net/virtio/virtio_ethdev.c
>> +++ b/drivers/net/virtio/virtio_ethdev.c
>> @@ -1679,11 +1679,6 @@ eth_virtio_dev_init(struct rte_eth_dev
>> *eth_dev)
>>   	if (ret < 0)
>>   		goto out;
>>   
>> -	/* Setup interrupt callback  */
>> -	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
>> -		rte_intr_callback_register(eth_dev->intr_handle,
>> -			virtio_interrupt_handler, eth_dev);
>> -
>>   	return 0;
>>   
>>   out:
>> @@ -1709,11 +1704,6 @@ eth_virtio_dev_uninit(struct rte_eth_dev
>> *eth_dev)
>>   	rte_free(eth_dev->data->mac_addrs);
>>   	eth_dev->data->mac_addrs = NULL;
>>   
>> -	/* reset interrupt callback  */
>> -	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
>> -		rte_intr_callback_unregister(eth_dev->intr_handle,
>> -						virtio_interrupt_han
>> dler,
>> -						eth_dev);
>>   	if (eth_dev->device)
>>   		rte_pci_unmap_device(RTE_ETH_DEV_TO_PCI(eth_dev));
>>   
>> @@ -1972,6 +1962,12 @@ virtio_dev_start(struct rte_eth_dev *dev)
>>   	    dev->data->dev_conf.intr_conf.rxq) {
>>   		virtio_intr_disable(dev);
>>   
>> +		/* Setup interrupt callback  */
>> +		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
>> +			rte_intr_callback_register(dev->intr_handle,
>> +						   virtio_interrupt_
>> handler,
>> +						   dev);
>> +
>>   		if (virtio_intr_enable(dev) < 0) {
>>   			PMD_DRV_LOG(ERR, "interrupt enable failed");
>>   			return -EIO;
>> @@ -2081,9 +2077,17 @@ virtio_dev_stop(struct rte_eth_dev *dev)
>>   	PMD_INIT_LOG(DEBUG, "stop");
>>   
>>   	rte_spinlock_lock(&hw->state_lock);
>> -	if (intr_conf->lsc || intr_conf->rxq)
>> +	if (intr_conf->lsc || intr_conf->rxq) {
>>   		virtio_intr_disable(dev);
>>   
>> +		/* Reset interrupt callback  */
>> +		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC) {
>> +			rte_intr_callback_unregister(dev-
>>> intr_handle,
>> +						     virtio_interrup
>> t_handler,
>> +						     dev);
>> +		}
>> +	}
>> +
>>   	hw->started = 0;
>>   	memset(&link, 0, sizeof(link));
>>   	rte_eth_linkstatus_set(dev, &link);
> 
> Hi, any chance the virtio and eal patches in this series could get a
> review? Thanks!
> 

Hi,

Sorry, I missed it because not delegated to me in patchwork.
Looking at it now!

Regards,
Maxime

Re: [dpdk-dev] [PATCH v2 1/3] net/virtio: register/unregister intr handler on start/stop

[Maxime Coquelin]

On 09/19/2018 02:57 PM, Luca Boccassi wrote:
> Register and unregister the virtio interrupt handler when the device is
> started and stopped. This allows a virtio device to be hotplugged or
> unplugged.
> 
> Fixes: c1f86306a026 ("virtio: add new driver")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Brian Russell <brussell@brocade.com>
> Signed-off-by: Luca Boccassi <bluca@debian.org>
> ---
>   drivers/net/virtio/virtio_ethdev.c | 26 +++++++++++++++-----------
>   1 file changed, 15 insertions(+), 11 deletions(-)
> 

Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Thanks,
Maxime

Re: [dpdk-dev] [PATCH v2 3/3] eal/linux: handle uio read failure in interrupt handler

[Thomas Monjalon]

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: 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);
> 

Re: [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Thomas Monjalon]

19/09/2018 17:47, Chas Williams:
> On Wed, Sep 19, 2018 at 8:58 AM Luca Boccassi <bluca@debian.org> wrote:
> >
> > The vmxnet3 driver can't call back into dev_close(), and possibly
> > dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
> > that those routines would want to clean up has already been released.
> > Further, for complete cleanup, it is necessary to release any of the
> > queue resources during dev_close().
> > This allows a vmxnet3 device to be hot-unplugged without leaking
> > queues.
> >
> > Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver implementation")
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Brian Russell <brussell@brocade.com>
> > Signed-off-by: Luca Boccassi <bluca@debian.org>
> > ---
> > v2: add back extra close() call in uninit() for buggy applications as
> >     requested by the reviewers, and add debug log noting the issue
> >
> >  drivers/net/vmxnet3/vmxnet3_ethdev.c | 35 +++++++++++++++++++++++-----
> >  1 file changed, 29 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > index f1596ab19d..98e5d01890 100644
> > --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > @@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
> >         if (rte_eal_process_type() != RTE_PROC_PRIMARY)
> >                 return 0;
> 
> This should probably be EPERM as well.  Out of scope though.
> 
> >
> > -       if (hw->adapter_stopped == 0)
> > +       if (hw->adapter_stopped == 0) {
> > +               PMD_INIT_LOG(DEBUG, "Device has not been closed.");
> >                 vmxnet3_dev_close(eth_dev);
> 
> This just seems wrong.  You have called uninit() will the driver is
> still busy.  Instead of "fixing" the state of the driver, return EBUSY
> here.

I agree.
If the port is not stopped, either you stop it or you return EBUSY.

Closing the device should be done outside of this check.
It is OK to close from uninit if the app did not close it.

[...]
> > +static void
> > +vmxnet3_free_queues(struct rte_eth_dev *dev)
> > +{
> > +       int i;
> > +
> > +       PMD_INIT_FUNC_TRACE();
> > +
> > +       for (i = 0; i < dev->data->nb_rx_queues; i++) {
> > +               void *rxq = dev->data->rx_queues[i];
> > +
> > +               vmxnet3_dev_rx_queue_release(rxq);
> > +       }
> > +       dev->data->nb_rx_queues = 0;
> > +
> > +       for (i = 0; i < dev->data->nb_tx_queues; i++) {
> > +               void *txq = dev->data->tx_queues[i];
> > +
> > +               vmxnet3_dev_tx_queue_release(txq);
> > +       }
> > +       dev->data->nb_tx_queues = 0;
> >  }
> >
> >  /*
> > @@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> >  static void
> >  vmxnet3_dev_close(struct rte_eth_dev *dev)
> >  {
> > -       struct vmxnet3_hw *hw = dev->data->dev_private;
> > -
> >         PMD_INIT_FUNC_TRACE();
> >
> >         vmxnet3_dev_stop(dev);
> > -       hw->adapter_stopped = 1;
> > +       vmxnet3_free_queues(dev);
> >  }

Good clean-up on dev_close.
You probably want to go further and set RTE_ETH_DEV_CLOSE_REMOVE for allowing
a real release of the port on close.
Note: every PMDs should migrate towards this behaviour.

To make things clear (I will write a doc for -rc2):
	- "stop" should be called by the app but the PMD is allowed to force it.
	- "close" may be called by the app, and the PMD should enforce it in uninit.
		With RTE_ETH_DEV_CLOSE_REMOVE flag, it must completely release the port.
	- "remove" (implemented in PMD as uninit) is responsible of closing
		ethdev ports if not already done, and release the shared resources
		which are not specific to a port. It removes the whole EAL rte_device.

PS: for any hotplug patch or questions, feel free to Cc me.

Re: [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Thomas Monjalon]

Any update or question for this patch?
If no update, it will miss 18.11.


27/10/2018 17:09, Thomas Monjalon:
> 19/09/2018 17:47, Chas Williams:
> > On Wed, Sep 19, 2018 at 8:58 AM Luca Boccassi <bluca@debian.org> wrote:
> > >
> > > The vmxnet3 driver can't call back into dev_close(), and possibly
> > > dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
> > > that those routines would want to clean up has already been released.
> > > Further, for complete cleanup, it is necessary to release any of the
> > > queue resources during dev_close().
> > > This allows a vmxnet3 device to be hot-unplugged without leaking
> > > queues.
> > >
> > > Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver implementation")
> > > Cc: stable@dpdk.org
> > >
> > > Signed-off-by: Brian Russell <brussell@brocade.com>
> > > Signed-off-by: Luca Boccassi <bluca@debian.org>
> > > ---
> > > v2: add back extra close() call in uninit() for buggy applications as
> > >     requested by the reviewers, and add debug log noting the issue
> > >
> > >  drivers/net/vmxnet3/vmxnet3_ethdev.c | 35 +++++++++++++++++++++++-----
> > >  1 file changed, 29 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > index f1596ab19d..98e5d01890 100644
> > > --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > @@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
> > >         if (rte_eal_process_type() != RTE_PROC_PRIMARY)
> > >                 return 0;
> > 
> > This should probably be EPERM as well.  Out of scope though.
> > 
> > >
> > > -       if (hw->adapter_stopped == 0)
> > > +       if (hw->adapter_stopped == 0) {
> > > +               PMD_INIT_LOG(DEBUG, "Device has not been closed.");
> > >                 vmxnet3_dev_close(eth_dev);
> > 
> > This just seems wrong.  You have called uninit() will the driver is
> > still busy.  Instead of "fixing" the state of the driver, return EBUSY
> > here.
> 
> I agree.
> If the port is not stopped, either you stop it or you return EBUSY.
> 
> Closing the device should be done outside of this check.
> It is OK to close from uninit if the app did not close it.
> 
> [...]
> > > +static void
> > > +vmxnet3_free_queues(struct rte_eth_dev *dev)
> > > +{
> > > +       int i;
> > > +
> > > +       PMD_INIT_FUNC_TRACE();
> > > +
> > > +       for (i = 0; i < dev->data->nb_rx_queues; i++) {
> > > +               void *rxq = dev->data->rx_queues[i];
> > > +
> > > +               vmxnet3_dev_rx_queue_release(rxq);
> > > +       }
> > > +       dev->data->nb_rx_queues = 0;
> > > +
> > > +       for (i = 0; i < dev->data->nb_tx_queues; i++) {
> > > +               void *txq = dev->data->tx_queues[i];
> > > +
> > > +               vmxnet3_dev_tx_queue_release(txq);
> > > +       }
> > > +       dev->data->nb_tx_queues = 0;
> > >  }
> > >
> > >  /*
> > > @@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> > >  static void
> > >  vmxnet3_dev_close(struct rte_eth_dev *dev)
> > >  {
> > > -       struct vmxnet3_hw *hw = dev->data->dev_private;
> > > -
> > >         PMD_INIT_FUNC_TRACE();
> > >
> > >         vmxnet3_dev_stop(dev);
> > > -       hw->adapter_stopped = 1;
> > > +       vmxnet3_free_queues(dev);
> > >  }
> 
> Good clean-up on dev_close.
> You probably want to go further and set RTE_ETH_DEV_CLOSE_REMOVE for allowing
> a real release of the port on close.
> Note: every PMDs should migrate towards this behaviour.
> 
> To make things clear (I will write a doc for -rc2):
> 	- "stop" should be called by the app but the PMD is allowed to force it.
> 	- "close" may be called by the app, and the PMD should enforce it in uninit.
> 		With RTE_ETH_DEV_CLOSE_REMOVE flag, it must completely release the port.
> 	- "remove" (implemented in PMD as uninit) is responsible of closing
> 		ethdev ports if not already done, and release the shared resources
> 		which are not specific to a port. It removes the whole EAL rte_device.
> 
> PS: for any hotplug patch or questions, feel free to Cc me.

Re: [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

Sorry, been otherwise busy - I can do what you and Chas have asked, but
the problem is that v1 already did that and the VMWare maintainers
asked to change it back. So can I assume that the v1 way is the way to
go?

On Wed, 2018-10-31 at 18:27 +0100, Thomas Monjalon wrote:
> Any update or question for this patch?
> If no update, it will miss 18.11.
> 
> 
> 27/10/2018 17:09, Thomas Monjalon:
> > 19/09/2018 17:47, Chas Williams:
> > > On Wed, Sep 19, 2018 at 8:58 AM Luca Boccassi <bluca@debian.org>
> > > wrote:
> > > > 
> > > > The vmxnet3 driver can't call back into dev_close(), and
> > > > possibly
> > > > dev_stop(), in dev_uninit().  When dev_uninit() is called,
> > > > anything
> > > > that those routines would want to clean up has already been
> > > > released.
> > > > Further, for complete cleanup, it is necessary to release any
> > > > of the
> > > > queue resources during dev_close().
> > > > This allows a vmxnet3 device to be hot-unplugged without
> > > > leaking
> > > > queues.
> > > > 
> > > > Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode
> > > > driver implementation")
> > > > Cc: stable@dpdk.org
> > > > 
> > > > Signed-off-by: Brian Russell <brussell@brocade.com>
> > > > Signed-off-by: Luca Boccassi <bluca@debian.org>
> > > > ---
> > > > v2: add back extra close() call in uninit() for buggy
> > > > applications as
> > > >     requested by the reviewers, and add debug log noting the
> > > > issue
> > > > 
> > > >  drivers/net/vmxnet3/vmxnet3_ethdev.c | 35
> > > > +++++++++++++++++++++++-----
> > > >  1 file changed, 29 insertions(+), 6 deletions(-)
> > > > 
> > > > diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > > b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > > index f1596ab19d..98e5d01890 100644
> > > > --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > > +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > > @@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev
> > > > *eth_dev)
> > > >         if (rte_eal_process_type() != RTE_PROC_PRIMARY)
> > > >                 return 0;
> > > 
> > > This should probably be EPERM as well.  Out of scope though.
> > > 
> > > > 
> > > > -       if (hw->adapter_stopped == 0)
> > > > +       if (hw->adapter_stopped == 0) {
> > > > +               PMD_INIT_LOG(DEBUG, "Device has not been
> > > > closed.");
> > > >                 vmxnet3_dev_close(eth_dev);
> > > 
> > > This just seems wrong.  You have called uninit() will the driver
> > > is
> > > still busy.  Instead of "fixing" the state of the driver, return
> > > EBUSY
> > > here.
> > 
> > I agree.
> > If the port is not stopped, either you stop it or you return EBUSY.
> > 
> > Closing the device should be done outside of this check.
> > It is OK to close from uninit if the app did not close it.
> > 
> > [...]
> > > > +static void
> > > > +vmxnet3_free_queues(struct rte_eth_dev *dev)
> > > > +{
> > > > +       int i;
> > > > +
> > > > +       PMD_INIT_FUNC_TRACE();
> > > > +
> > > > +       for (i = 0; i < dev->data->nb_rx_queues; i++) {
> > > > +               void *rxq = dev->data->rx_queues[i];
> > > > +
> > > > +               vmxnet3_dev_rx_queue_release(rxq);
> > > > +       }
> > > > +       dev->data->nb_rx_queues = 0;
> > > > +
> > > > +       for (i = 0; i < dev->data->nb_tx_queues; i++) {
> > > > +               void *txq = dev->data->tx_queues[i];
> > > > +
> > > > +               vmxnet3_dev_tx_queue_release(txq);
> > > > +       }
> > > > +       dev->data->nb_tx_queues = 0;
> > > >  }
> > > > 
> > > >  /*
> > > > @@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> > > >  static void
> > > >  vmxnet3_dev_close(struct rte_eth_dev *dev)
> > > >  {
> > > > -       struct vmxnet3_hw *hw = dev->data->dev_private;
> > > > -
> > > >         PMD_INIT_FUNC_TRACE();
> > > > 
> > > >         vmxnet3_dev_stop(dev);
> > > > -       hw->adapter_stopped = 1;
> > > > +       vmxnet3_free_queues(dev);
> > > >  }
> > 
> > Good clean-up on dev_close.
> > You probably want to go further and set RTE_ETH_DEV_CLOSE_REMOVE
> > for allowing
> > a real release of the port on close.
> > Note: every PMDs should migrate towards this behaviour.
> > 
> > To make things clear (I will write a doc for -rc2):
> > 	- "stop" should be called by the app but the PMD is allowed to
> > force it.
> > 	- "close" may be called by the app, and the PMD should enforce
> > it in uninit.
> > 		With RTE_ETH_DEV_CLOSE_REMOVE flag, it must completely
> > release the port.
> > 	- "remove" (implemented in PMD as uninit) is responsible of
> > closing
> > 		ethdev ports if not already done, and release the
> > shared resources
> > 		which are not specific to a port. It removes the whole
> > EAL rte_device.
> > 
> > PS: for any hotplug patch or questions, feel free to Cc me.
> 
> 
> 
> 
> 

-- 
Kind regards,
Luca Boccassi

Re: [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Thomas Monjalon]

31/10/2018 18:46, Luca Boccassi:
> Sorry, been otherwise busy - I can do what you and Chas have asked, but
> the problem is that v1 already did that and the VMWare maintainers
> asked to change it back. So can I assume that the v1 way is the way to
> go?

I am expecting an answer from the vmxnet3 maintainer,
or other VMware developpers.
If they don't reply, we should work without them,
and ask for a new maintainer in the community.

I assume you can now work on a v3 reproducing what was done in v1.


> On Wed, 2018-10-31 at 18:27 +0100, Thomas Monjalon wrote:
> > Any update or question for this patch?
> > If no update, it will miss 18.11.
> > 
> > 
> > 27/10/2018 17:09, Thomas Monjalon:
> > > 19/09/2018 17:47, Chas Williams:
> > > > On Wed, Sep 19, 2018 at 8:58 AM Luca Boccassi <bluca@debian.org>
> > > > wrote:
> > > > > 
> > > > > The vmxnet3 driver can't call back into dev_close(), and
> > > > > possibly
> > > > > dev_stop(), in dev_uninit().  When dev_uninit() is called,
> > > > > anything
> > > > > that those routines would want to clean up has already been
> > > > > released.
> > > > > Further, for complete cleanup, it is necessary to release any
> > > > > of the
> > > > > queue resources during dev_close().
> > > > > This allows a vmxnet3 device to be hot-unplugged without
> > > > > leaking
> > > > > queues.
> > > > > 
> > > > > Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode
> > > > > driver implementation")
> > > > > Cc: stable@dpdk.org
> > > > > 
> > > > > Signed-off-by: Brian Russell <brussell@brocade.com>
> > > > > Signed-off-by: Luca Boccassi <bluca@debian.org>
> > > > > ---
> > > > > v2: add back extra close() call in uninit() for buggy
> > > > > applications as
> > > > >     requested by the reviewers, and add debug log noting the
> > > > > issue
> > > > > 
> > > > >  drivers/net/vmxnet3/vmxnet3_ethdev.c | 35
> > > > > +++++++++++++++++++++++-----
> > > > >  1 file changed, 29 insertions(+), 6 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > > > b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > > > index f1596ab19d..98e5d01890 100644
> > > > > --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > > > +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
> > > > > @@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev
> > > > > *eth_dev)
> > > > >         if (rte_eal_process_type() != RTE_PROC_PRIMARY)
> > > > >                 return 0;
> > > > 
> > > > This should probably be EPERM as well.  Out of scope though.
> > > > 
> > > > > 
> > > > > -       if (hw->adapter_stopped == 0)
> > > > > +       if (hw->adapter_stopped == 0) {
> > > > > +               PMD_INIT_LOG(DEBUG, "Device has not been
> > > > > closed.");
> > > > >                 vmxnet3_dev_close(eth_dev);
> > > > 
> > > > This just seems wrong.  You have called uninit() will the driver
> > > > is
> > > > still busy.  Instead of "fixing" the state of the driver, return
> > > > EBUSY
> > > > here.
> > > 
> > > I agree.
> > > If the port is not stopped, either you stop it or you return EBUSY.
> > > 
> > > Closing the device should be done outside of this check.
> > > It is OK to close from uninit if the app did not close it.
> > > 
> > > [...]
> > > > > +static void
> > > > > +vmxnet3_free_queues(struct rte_eth_dev *dev)
> > > > > +{
> > > > > +       int i;
> > > > > +
> > > > > +       PMD_INIT_FUNC_TRACE();
> > > > > +
> > > > > +       for (i = 0; i < dev->data->nb_rx_queues; i++) {
> > > > > +               void *rxq = dev->data->rx_queues[i];
> > > > > +
> > > > > +               vmxnet3_dev_rx_queue_release(rxq);
> > > > > +       }
> > > > > +       dev->data->nb_rx_queues = 0;
> > > > > +
> > > > > +       for (i = 0; i < dev->data->nb_tx_queues; i++) {
> > > > > +               void *txq = dev->data->tx_queues[i];
> > > > > +
> > > > > +               vmxnet3_dev_tx_queue_release(txq);
> > > > > +       }
> > > > > +       dev->data->nb_tx_queues = 0;
> > > > >  }
> > > > > 
> > > > >  /*
> > > > > @@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
> > > > >  static void
> > > > >  vmxnet3_dev_close(struct rte_eth_dev *dev)
> > > > >  {
> > > > > -       struct vmxnet3_hw *hw = dev->data->dev_private;
> > > > > -
> > > > >         PMD_INIT_FUNC_TRACE();
> > > > > 
> > > > >         vmxnet3_dev_stop(dev);
> > > > > -       hw->adapter_stopped = 1;
> > > > > +       vmxnet3_free_queues(dev);
> > > > >  }
> > > 
> > > Good clean-up on dev_close.
> > > You probably want to go further and set RTE_ETH_DEV_CLOSE_REMOVE
> > > for allowing
> > > a real release of the port on close.
> > > Note: every PMDs should migrate towards this behaviour.
> > > 
> > > To make things clear (I will write a doc for -rc2):
> > > 	- "stop" should be called by the app but the PMD is allowed to
> > > force it.
> > > 	- "close" may be called by the app, and the PMD should enforce
> > > it in uninit.
> > > 		With RTE_ETH_DEV_CLOSE_REMOVE flag, it must completely
> > > release the port.
> > > 	- "remove" (implemented in PMD as uninit) is responsible of
> > > closing
> > > 		ethdev ports if not already done, and release the
> > > shared resources
> > > 		which are not specific to a port. It removes the whole
> > > EAL rte_device.
> > > 
> > > PS: for any hotplug patch or questions, feel free to Cc me.
> > 
> > 
> > 
> > 
> > 
> 
> 

[dpdk-dev] [PATCH v3 1/3] net/virtio: register/unregister intr handler on start/stop

[Luca Boccassi]

Register and unregister the virtio interrupt handler when the device is
started and stopped. This allows a virtio device to be hotplugged or
unplugged.

Fixes: c1f86306a026 ("virtio: add new driver")
Cc: stable@dpdk.org

Signed-off-by: Brian Russell <brussell@brocade.com>
Signed-off-by: Luca Boccassi <bluca@debian.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 drivers/net/virtio/virtio_ethdev.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 10a7e3fcc..da8717726 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1679,11 +1679,6 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 	if (ret < 0)
 		goto out;
 
-	/* Setup interrupt callback  */
-	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
-		rte_intr_callback_register(eth_dev->intr_handle,
-			virtio_interrupt_handler, eth_dev);
-
 	return 0;
 
 out:
@@ -1706,11 +1701,6 @@ eth_virtio_dev_uninit(struct rte_eth_dev *eth_dev)
 	eth_dev->tx_pkt_burst = NULL;
 	eth_dev->rx_pkt_burst = NULL;
 
-	/* reset interrupt callback  */
-	if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
-		rte_intr_callback_unregister(eth_dev->intr_handle,
-						virtio_interrupt_handler,
-						eth_dev);
 	if (eth_dev->device)
 		rte_pci_unmap_device(RTE_ETH_DEV_TO_PCI(eth_dev));
 
@@ -1969,6 +1959,12 @@ virtio_dev_start(struct rte_eth_dev *dev)
 	    dev->data->dev_conf.intr_conf.rxq) {
 		virtio_intr_disable(dev);
 
+		/* Setup interrupt callback  */
+		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC)
+			rte_intr_callback_register(dev->intr_handle,
+						   virtio_interrupt_handler,
+						   dev);
+
 		if (virtio_intr_enable(dev) < 0) {
 			PMD_DRV_LOG(ERR, "interrupt enable failed");
 			return -EIO;
@@ -2078,9 +2074,17 @@ virtio_dev_stop(struct rte_eth_dev *dev)
 	PMD_INIT_LOG(DEBUG, "stop");
 
 	rte_spinlock_lock(&hw->state_lock);
-	if (intr_conf->lsc || intr_conf->rxq)
+	if (intr_conf->lsc || intr_conf->rxq) {
 		virtio_intr_disable(dev);
 
+		/* Reset interrupt callback  */
+		if (dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC) {
+			rte_intr_callback_unregister(dev->intr_handle,
+						     virtio_interrupt_handler,
+						     dev);
+		}
+	}
+
 	hw->started = 0;
 	memset(&link, 0, sizeof(link));
 	rte_eth_linkstatus_set(dev, &link);
-- 
2.19.1

[dpdk-dev] [PATCH v3 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Luca Boccassi]

The vmxnet3 driver can't call back into dev_close(), and possibly
dev_stop(), in dev_uninit().  When dev_uninit() is called, anything
that those routines would want to clean up has already been released.
Further, for complete cleanup, it is necessary to release any of the
queue resources during dev_close().
This allows a vmxnet3 device to be hot-unplugged without leaking
queues.
Also set RTE_ETH_DEV_CLOSE_REMOVE on close so that the port resources
can be deallocated.
Return EBUSY if remove is called before stop.

Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver implementation")
Cc: stable@dpdk.org

Signed-off-by: Brian Russell <brussell@brocade.com>
Signed-off-by: Luca Boccassi <bluca@debian.org>
---
v2: add back extra close() call in uninit() for buggy applications as
    requested by the reviewers, and add debug log noting the issue
v3: remove extra close() call in uninit() as requested, and return
    -EBUSY instead.
    set RTE_ETH_DEV_CLOSE_REMOVE in close().

 drivers/net/vmxnet3/vmxnet3_ethdev.c | 43 +++++++++++++++++++++++-----
 1 file changed, 36 insertions(+), 7 deletions(-)

diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c b/drivers/net/vmxnet3/vmxnet3_ethdev.c
index 41bcd450a..84acd9dbb 100644
--- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
+++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
@@ -360,8 +360,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
 	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
 		return 0;
 
-	if (hw->adapter_stopped == 0)
-		vmxnet3_dev_close(eth_dev);
+	if (hw->adapter_stopped == 0) {
+		PMD_INIT_LOG(DEBUG, "Device has not been closed.");
+		return -EBUSY;
+	}
 
 	eth_dev->dev_ops = NULL;
 	eth_dev->rx_pkt_burst = NULL;
@@ -805,7 +807,7 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	PMD_INIT_FUNC_TRACE();
 
 	if (hw->adapter_stopped == 1) {
-		PMD_INIT_LOG(DEBUG, "Device already closed.");
+		PMD_INIT_LOG(DEBUG, "Device already stopped.");
 		return;
 	}
 
@@ -829,7 +831,6 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	/* reset the device */
 	VMXNET3_WRITE_BAR1_REG(hw, VMXNET3_REG_CMD, VMXNET3_CMD_RESET_DEV);
 	PMD_INIT_LOG(DEBUG, "Device reset.");
-	hw->adapter_stopped = 0;
 
 	vmxnet3_dev_clear_queues(dev);
 
@@ -839,6 +840,30 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 	link.link_speed = ETH_SPEED_NUM_10G;
 	link.link_autoneg = ETH_LINK_FIXED;
 	rte_eth_linkstatus_set(dev, &link);
+
+	hw->adapter_stopped = 1;
+}
+
+static void
+vmxnet3_free_queues(struct rte_eth_dev *dev)
+{
+	int i;
+
+	PMD_INIT_FUNC_TRACE();
+
+	for (i = 0; i < dev->data->nb_rx_queues; i++) {
+		void *rxq = dev->data->rx_queues[i];
+
+		vmxnet3_dev_rx_queue_release(rxq);
+	}
+	dev->data->nb_rx_queues = 0;
+
+	for (i = 0; i < dev->data->nb_tx_queues; i++) {
+		void *txq = dev->data->tx_queues[i];
+
+		vmxnet3_dev_tx_queue_release(txq);
+	}
+	dev->data->nb_tx_queues = 0;
 }
 
 /*
@@ -847,12 +872,16 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
 static void
 vmxnet3_dev_close(struct rte_eth_dev *dev)
 {
-	struct vmxnet3_hw *hw = dev->data->dev_private;
-
 	PMD_INIT_FUNC_TRACE();
 
 	vmxnet3_dev_stop(dev);
-	hw->adapter_stopped = 1;
+	vmxnet3_free_queues(dev);
+
+	/*
+	 * flag to rte_eth_dev_close() that it should release the port resources
+	 * (calling rte_eth_dev_release_port()) in addition to closing it.
+	 */
+	dev->data->dev_flags |= RTE_ETH_DEV_CLOSE_REMOVE;
 }
 
 static void
-- 
2.19.1

[dpdk-dev] [PATCH v3 3/3] eal/linux: handle uio read failure in interrupt handler

[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: 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 39252a887..cbac451e1 100644
--- a/lib/librte_eal/linuxapp/eal/eal_interrupts.c
+++ b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
@@ -700,7 +700,7 @@ 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;
 
@@ -780,6 +780,23 @@ 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);
-- 
2.19.1

Re: [dpdk-dev] [PATCH v2 2/3] net/vmxnet3: fix vmxnet3 dev_uninit() hot-unplug

[Louis Luo]

Hey I'm taking paternity leave now so late on response.

The v1 was different from what Thomas asked for and (hw->adapter_stopped == 0) was ignored (see cited below). So we felt uncomfortable about that as there is no guarantee that the device has been closed before calling uninit. Now that you fail the uninit call for non-stopped device and return EBUSY, I'm fine with it.

Regards,
Louis

static int
eth_vmxnet3_dev_uninit(struct rte_eth_dev *eth_dev)
{
-	struct vmxnet3_hw *hw = eth_dev->data->dev_private;
-
	PMD_INIT_FUNC_TRACE();
	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
		return 0;
-	if (hw->adapter_stopped == 0)
-		vmxnet3_dev_close(eth_dev);
-
	eth_dev->dev_ops = NULL;
	eth_dev->rx_pkt_burst = NULL;
	eth_dev->tx_pkt_burst = NULL;

On 10/31/18, 10:46 AM, "Luca Boccassi" <bluca@debian.org> wrote:

    Sorry, been otherwise busy - I can do what you and Chas have asked, but
    the problem is that v1 already did that and the VMWare maintainers
    asked to change it back. So can I assume that the v1 way is the way to
    go?
    
    On Wed, 2018-10-31 at 18:27 +0100, Thomas Monjalon wrote:
    > Any update or question for this patch?
    > If no update, it will miss 18.11.
    > 
    > 
    > 27/10/2018 17:09, Thomas Monjalon:
    > > 19/09/2018 17:47, Chas Williams:
    > > > On Wed, Sep 19, 2018 at 8:58 AM Luca Boccassi <bluca@debian.org>
    > > > wrote:
    > > > > 
    > > > > The vmxnet3 driver can't call back into dev_close(), and
    > > > > possibly
    > > > > dev_stop(), in dev_uninit().  When dev_uninit() is called,
    > > > > anything
    > > > > that those routines would want to clean up has already been
    > > > > released.
    > > > > Further, for complete cleanup, it is necessary to release any
    > > > > of the
    > > > > queue resources during dev_close().
    > > > > This allows a vmxnet3 device to be hot-unplugged without
    > > > > leaking
    > > > > queues.
    > > > > 
    > > > > Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode
    > > > > driver implementation")
    > > > > Cc: stable@dpdk.org
    > > > > 
    > > > > Signed-off-by: Brian Russell <brussell@brocade.com>
    > > > > Signed-off-by: Luca Boccassi <bluca@debian.org>
    > > > > ---
    > > > > v2: add back extra close() call in uninit() for buggy
    > > > > applications as
    > > > >     requested by the reviewers, and add debug log noting the
    > > > > issue
    > > > > 
    > > > >  drivers/net/vmxnet3/vmxnet3_ethdev.c | 35
    > > > > +++++++++++++++++++++++-----
    > > > >  1 file changed, 29 insertions(+), 6 deletions(-)
    > > > > 
    > > > > diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c
    > > > > b/drivers/net/vmxnet3/vmxnet3_ethdev.c
    > > > > index f1596ab19d..98e5d01890 100644
    > > > > --- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
    > > > > +++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
    > > > > @@ -354,8 +354,10 @@ eth_vmxnet3_dev_uninit(struct rte_eth_dev
    > > > > *eth_dev)
    > > > >         if (rte_eal_process_type() != RTE_PROC_PRIMARY)
    > > > >                 return 0;
    > > > 
    > > > This should probably be EPERM as well.  Out of scope though.
    > > > 
    > > > > 
    > > > > -       if (hw->adapter_stopped == 0)
    > > > > +       if (hw->adapter_stopped == 0) {
    > > > > +               PMD_INIT_LOG(DEBUG, "Device has not been
    > > > > closed.");
    > > > >                 vmxnet3_dev_close(eth_dev);
    > > > 
    > > > This just seems wrong.  You have called uninit() will the driver
    > > > is
    > > > still busy.  Instead of "fixing" the state of the driver, return
    > > > EBUSY
    > > > here.
    > > 
    > > I agree.
    > > If the port is not stopped, either you stop it or you return EBUSY.
    > > 
    > > Closing the device should be done outside of this check.
    > > It is OK to close from uninit if the app did not close it.
    > > 
    > > [...]
    > > > > +static void
    > > > > +vmxnet3_free_queues(struct rte_eth_dev *dev)
    > > > > +{
    > > > > +       int i;
    > > > > +
    > > > > +       PMD_INIT_FUNC_TRACE();
    > > > > +
    > > > > +       for (i = 0; i < dev->data->nb_rx_queues; i++) {
    > > > > +               void *rxq = dev->data->rx_queues[i];
    > > > > +
    > > > > +               vmxnet3_dev_rx_queue_release(rxq);
    > > > > +       }
    > > > > +       dev->data->nb_rx_queues = 0;
    > > > > +
    > > > > +       for (i = 0; i < dev->data->nb_tx_queues; i++) {
    > > > > +               void *txq = dev->data->tx_queues[i];
    > > > > +
    > > > > +               vmxnet3_dev_tx_queue_release(txq);
    > > > > +       }
    > > > > +       dev->data->nb_tx_queues = 0;
    > > > >  }
    > > > > 
    > > > >  /*
    > > > > @@ -844,12 +869,10 @@ vmxnet3_dev_stop(struct rte_eth_dev *dev)
    > > > >  static void
    > > > >  vmxnet3_dev_close(struct rte_eth_dev *dev)
    > > > >  {
    > > > > -       struct vmxnet3_hw *hw = dev->data->dev_private;
    > > > > -
    > > > >         PMD_INIT_FUNC_TRACE();
    > > > > 
    > > > >         vmxnet3_dev_stop(dev);
    > > > > -       hw->adapter_stopped = 1;
    > > > > +       vmxnet3_free_queues(dev);
    > > > >  }
    > > 
    > > Good clean-up on dev_close.
    > > You probably want to go further and set RTE_ETH_DEV_CLOSE_REMOVE
    > > for allowing
    > > a real release of the port on close.
    > > Note: every PMDs should migrate towards this behaviour.
    > > 
    > > To make things clear (I will write a doc for -rc2):
    > > 	- "stop" should be called by the app but the PMD is allowed to
    > > force it.
    > > 	- "close" may be called by the app, and the PMD should enforce
    > > it in uninit.
    > > 		With RTE_ETH_DEV_CLOSE_REMOVE flag, it must completely
    > > release the port.
    > > 	- "remove" (implemented in PMD as uninit) is responsible of
    > > closing
    > > 		ethdev ports if not already done, and release the
    > > shared resources
    > > 		which are not specific to a port. It removes the whole
    > > EAL rte_device.
    > > 
    > > PS: for any hotplug patch or questions, feel free to Cc me.
    > 
    > 
    > 
    > 
    > 
    
    -- 
    Kind regards,
    Luca Boccassi
    

Re: [dpdk-dev] [dpdk-stable] [PATCH v3 1/3] net/virtio: register/unregister intr handler on start/stop

[Thomas Monjalon]

31/10/2018 19:39, Luca Boccassi:
> Register and unregister the virtio interrupt handler when the device is
> started and stopped. This allows a virtio device to be hotplugged or
> unplugged.
> 
> Fixes: c1f86306a026 ("virtio: add new driver")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Brian Russell <brussell@brocade.com>
> Signed-off-by: Luca Boccassi <bluca@debian.org>
> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Series applied, thanks

Re: [dpdk-dev] [dpdk-stable] [PATCH v3 1/3] net/virtio: register/unregister intr handler on start/stop

[Luca Boccassi]

On Fri, 2018-11-02 at 10:49 +0100, Thomas Monjalon wrote:
> 31/10/2018 19:39, Luca Boccassi:
> > Register and unregister the virtio interrupt handler when the
> > device is
> > started and stopped. This allows a virtio device to be hotplugged
> > or
> > unplugged.
> > 
> > Fixes: c1f86306a026 ("virtio: add new driver")
> > Cc: stable@dpdk.org
> > 
> > Signed-off-by: Brian Russell <brussell@brocade.com>
> > Signed-off-by: Luca Boccassi <bluca@debian.org>
> > Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> 
> Series applied, thanks

Thanks!

-- 
Kind regards,
Luca Boccassi