2013-03-06 17:46:40

by Bhavesh Davda

[permalink] [raw]
Subject: [PATCH net-next] vmxnet3: prevent div-by-zero panic when ring resizing uninitialized dev

Linux is free to call ethtool ops as soon as a netdev exists when probe
finishes. However, we only allocate vmxnet3 tx/rx queues and initialize the
rx_buf_per_pkt field in struct vmxnet3_adapter when the interface is
opened (UP).

Signed-off-by: Bhavesh Davda <[email protected]>
Signed-off-by: Shreyas N Bhatewara <[email protected]>
---
drivers/net/vmxnet3/vmxnet3_drv.c | 3 ++-
drivers/net/vmxnet3/vmxnet3_ethtool.c | 6 ++++++
drivers/net/vmxnet3/vmxnet3_int.h | 4 ++--
3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
index 4aad350..bfc5898 100644
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -2922,7 +2922,7 @@ vmxnet3_probe_device(struct pci_dev *pdev,
(int)num_online_cpus());
else
#endif
- num_rx_queues = 1;
+ num_rx_queues = 1;
num_rx_queues = rounddown_pow_of_two(num_rx_queues);

if (enable_mq)
@@ -2958,6 +2958,7 @@ vmxnet3_probe_device(struct pci_dev *pdev,

adapter->num_rx_queues = num_rx_queues;
adapter->num_tx_queues = num_tx_queues;
+ adapter->rx_buf_per_pkt = 1;

size = sizeof(struct Vmxnet3_TxQueueDesc) * adapter->num_tx_queues;
size += sizeof(struct Vmxnet3_RxQueueDesc) * adapter->num_rx_queues;
diff --git a/drivers/net/vmxnet3/vmxnet3_ethtool.c b/drivers/net/vmxnet3/vmxnet3_ethtool.c
index a0feb17..0a4fc9e 100644
--- a/drivers/net/vmxnet3/vmxnet3_ethtool.c
+++ b/drivers/net/vmxnet3/vmxnet3_ethtool.c
@@ -472,6 +472,12 @@ vmxnet3_set_ringparam(struct net_device *netdev,
VMXNET3_RX_RING_MAX_SIZE)
return -EINVAL;

+ /* if adapter not yet initialized, do nothing */
+ if (adapter->rx_buf_per_pkt == 0) {
+ netdev_info(netdev,
+ "adapter not completely initialized, ring size cannot be changed yet\n");
+ return -EOPNOTSUPP;
+ }

/* round it up to a multiple of VMXNET3_RING_SIZE_ALIGN */
new_tx_ring_size = (param->tx_pending + VMXNET3_RING_SIZE_MASK) &
diff --git a/drivers/net/vmxnet3/vmxnet3_int.h b/drivers/net/vmxnet3/vmxnet3_int.h
index 3198384..3541814 100644
--- a/drivers/net/vmxnet3/vmxnet3_int.h
+++ b/drivers/net/vmxnet3/vmxnet3_int.h
@@ -70,10 +70,10 @@
/*
* Version numbers
*/
-#define VMXNET3_DRIVER_VERSION_STRING "1.1.29.0-k"
+#define VMXNET3_DRIVER_VERSION_STRING "1.1.30.0-k"

/* a 32-bit int, each byte encode a verion number in VMXNET3_DRIVER_VERSION */
-#define VMXNET3_DRIVER_VERSION_NUM 0x01011D00
+#define VMXNET3_DRIVER_VERSION_NUM 0x01011E00

#if defined(CONFIG_PCI_MSI)
/* RSS only makes sense if MSI-X is supported. */
--
1.7.1


2013-03-06 20:38:46

by David Miller

[permalink] [raw]
Subject: Re: [PATCH net-next] vmxnet3: prevent div-by-zero panic when ring resizing uninitialized dev

From: Bhavesh Davda <[email protected]>
Date: Wed, 6 Mar 2013 09:46:24 -0800

> Linux is free to call ethtool ops as soon as a netdev exists when probe
> finishes. However, we only allocate vmxnet3 tx/rx queues and initialize the
> rx_buf_per_pkt field in struct vmxnet3_adapter when the interface is
> opened (UP).
>
> Signed-off-by: Bhavesh Davda <[email protected]>
> Signed-off-by: Shreyas N Bhatewara <[email protected]>
> ---
> drivers/net/vmxnet3/vmxnet3_drv.c | 3 ++-
> drivers/net/vmxnet3/vmxnet3_ethtool.c | 6 ++++++
> drivers/net/vmxnet3/vmxnet3_int.h | 4 ++--
> 3 files changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
> index 4aad350..bfc5898 100644
> --- a/drivers/net/vmxnet3/vmxnet3_drv.c
> +++ b/drivers/net/vmxnet3/vmxnet3_drv.c
> @@ -2922,7 +2922,7 @@ vmxnet3_probe_device(struct pci_dev *pdev,
> (int)num_online_cpus());
> else
> #endif
> - num_rx_queues = 1;
> + num_rx_queues = 1;

Why are you un-indenting this else branch? Please don't do that.

2013-03-06 22:00:14

by Bhavesh Davda

[permalink] [raw]
Subject: Re: [PATCH net-next] vmxnet3: prevent div-by-zero panic when ring resizing uninitialized dev

> > ---
> > drivers/net/vmxnet3/vmxnet3_drv.c | 3 ++-
> > drivers/net/vmxnet3/vmxnet3_ethtool.c | 6 ++++++
> > drivers/net/vmxnet3/vmxnet3_int.h | 4 ++--
> > 3 files changed, 10 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c
> > b/drivers/net/vmxnet3/vmxnet3_drv.c
> > index 4aad350..bfc5898 100644
> > --- a/drivers/net/vmxnet3/vmxnet3_drv.c
> > +++ b/drivers/net/vmxnet3/vmxnet3_drv.c
> > @@ -2922,7 +2922,7 @@ vmxnet3_probe_device(struct pci_dev *pdev,
> > (int)num_online_cpus());
> > else
> > #endif
> > - num_rx_queues = 1;
> > + num_rx_queues = 1;
>
> Why are you un-indenting this else branch? Please don't do that
>

Just to annoy you :) [Sorry, couldn't resist.]

I'm sorry I didn't notice I was breaking the indent of the else branch. For some reason checkpatch didn't complain.

While at it, I'm also changing the netdev_info to netdev_err in vmxnet3_ethtool.c.

You didn't explicitly ask for it, so I wasn't sure if I should repost the patch. I'm going to repost it any way and leave it up to you on which patch you want to apply.

Thanks.

- Bhavesh

2013-03-06 22:05:06

by Bhavesh Davda

[permalink] [raw]
Subject: [PATCH net-next] vmxnet3: prevent div-by-zero panic when ring resizing uninitialized dev

Linux is free to call ethtool ops as soon as a netdev exists when probe
finishes. However, we only allocate vmxnet3 tx/rx queues and initialize the
rx_buf_per_pkt field in struct vmxnet3_adapter when the interface is
opened (UP).

Signed-off-by: Bhavesh Davda <[email protected]>
Signed-off-by: Shreyas N Bhatewara <[email protected]>
---
drivers/net/vmxnet3/vmxnet3_drv.c | 1 +
drivers/net/vmxnet3/vmxnet3_ethtool.c | 6 ++++++
drivers/net/vmxnet3/vmxnet3_int.h | 4 ++--
3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
index 4aad350..eae7a03 100644
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -2958,6 +2958,7 @@ vmxnet3_probe_device(struct pci_dev *pdev,

adapter->num_rx_queues = num_rx_queues;
adapter->num_tx_queues = num_tx_queues;
+ adapter->rx_buf_per_pkt = 1;

size = sizeof(struct Vmxnet3_TxQueueDesc) * adapter->num_tx_queues;
size += sizeof(struct Vmxnet3_RxQueueDesc) * adapter->num_rx_queues;
diff --git a/drivers/net/vmxnet3/vmxnet3_ethtool.c b/drivers/net/vmxnet3/vmxnet3_ethtool.c
index a0feb17..63a1243 100644
--- a/drivers/net/vmxnet3/vmxnet3_ethtool.c
+++ b/drivers/net/vmxnet3/vmxnet3_ethtool.c
@@ -472,6 +472,12 @@ vmxnet3_set_ringparam(struct net_device *netdev,
VMXNET3_RX_RING_MAX_SIZE)
return -EINVAL;

+ /* if adapter not yet initialized, do nothing */
+ if (adapter->rx_buf_per_pkt == 0) {
+ netdev_err(netdev, "adapter not completely initialized, "
+ "ring size cannot be changed yet\n");
+ return -EOPNOTSUPP;
+ }

/* round it up to a multiple of VMXNET3_RING_SIZE_ALIGN */
new_tx_ring_size = (param->tx_pending + VMXNET3_RING_SIZE_MASK) &
diff --git a/drivers/net/vmxnet3/vmxnet3_int.h b/drivers/net/vmxnet3/vmxnet3_int.h
index 3198384..3541814 100644
--- a/drivers/net/vmxnet3/vmxnet3_int.h
+++ b/drivers/net/vmxnet3/vmxnet3_int.h
@@ -70,10 +70,10 @@
/*
* Version numbers
*/
-#define VMXNET3_DRIVER_VERSION_STRING "1.1.29.0-k"
+#define VMXNET3_DRIVER_VERSION_STRING "1.1.30.0-k"

/* a 32-bit int, each byte encode a verion number in VMXNET3_DRIVER_VERSION */
-#define VMXNET3_DRIVER_VERSION_NUM 0x01011D00
+#define VMXNET3_DRIVER_VERSION_NUM 0x01011E00

#if defined(CONFIG_PCI_MSI)
/* RSS only makes sense if MSI-X is supported. */
--
1.7.1

2013-03-06 22:09:40

by David Miller

[permalink] [raw]
Subject: Re: [PATCH net-next] vmxnet3: prevent div-by-zero panic when ring resizing uninitialized dev

From: Bhavesh Davda <[email protected]>
Date: Wed, 6 Mar 2013 14:04:53 -0800

> Linux is free to call ethtool ops as soon as a netdev exists when probe
> finishes. However, we only allocate vmxnet3 tx/rx queues and initialize the
> rx_buf_per_pkt field in struct vmxnet3_adapter when the interface is
> opened (UP).
>
> Signed-off-by: Bhavesh Davda <[email protected]>
> Signed-off-by: Shreyas N Bhatewara <[email protected]>

Maybe this is more appropriate for 'net' rather than 'net-next'?

2013-03-07 21:11:32

by David Miller

[permalink] [raw]
Subject: Re: [PATCH net-next] vmxnet3: prevent div-by-zero panic when ring resizing uninitialized dev

From: Bhavesh Davda <[email protected]>
Date: Wed, 6 Mar 2013 14:04:53 -0800

> Linux is free to call ethtool ops as soon as a netdev exists when probe
> finishes. However, we only allocate vmxnet3 tx/rx queues and initialize the
> rx_buf_per_pkt field in struct vmxnet3_adapter when the interface is
> opened (UP).
>
> Signed-off-by: Bhavesh Davda <[email protected]>
> Signed-off-by: Shreyas N Bhatewara <[email protected]>

As discussed yesterday, I'm applying this to 'net', thanks.