* [PATCH net] tg3: prevent ifup/ifdown during PCI error recovery
@ 2014-08-27 13:01 Ivan Vecera
2014-08-28 23:28 ` Prashant
0 siblings, 1 reply; 3+ messages in thread
From: Ivan Vecera @ 2014-08-27 13:01 UTC (permalink / raw)
To: netdev; +Cc: Prashant Sreedharan, Michael Chan
The patch fixes race conditions between PCI error recovery callbacks and
potential ifup/ifdown.
First, if ifup (tg3_open) is called between tg3_io_error_detected() and
tg3_io_resume() then tp->timer is armed twice before expiry. Once during
tg3_open() and again during tg3_io_resume(). This results in BUG
at kernel/time/timer.c:945.
Second, if ifdown (tg3_close) is called between tg3_io_error_detected()
and tg3_io_resume() then tg3_napi_disable() is called twice without
a tg3_napi_enable between. Once during tg3_io_error_detected() and again
during tg3_close(). The tg3_io_resume() then hangs on rtnl_lock().
Cc: Prashant Sreedharan <prashant@broadcom.com>
Cc: Michael Chan <mchan@broadcom.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
drivers/net/ethernet/broadcom/tg3.c | 10 ++++++++++
drivers/net/ethernet/broadcom/tg3.h | 1 +
2 files changed, 11 insertions(+)
diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 3ac5d23..8d9c774 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -11617,6 +11617,9 @@ static int tg3_open(struct net_device *dev)
struct tg3 *tp = netdev_priv(dev);
int err;
+ if (tp->pcierr_recovery)
+ return -EAGAIN;
+
if (tp->fw_needed) {
err = tg3_request_firmware(tp);
if (tg3_asic_rev(tp) == ASIC_REV_57766) {
@@ -11674,6 +11677,9 @@ static int tg3_close(struct net_device *dev)
{
struct tg3 *tp = netdev_priv(dev);
+ if (tp->pcierr_recovery)
+ return -EAGAIN;
+
tg3_ptp_fini(tp);
tg3_stop(tp);
@@ -17561,6 +17567,7 @@ static int tg3_init_one(struct pci_dev *pdev,
tp->rx_mode = TG3_DEF_RX_MODE;
tp->tx_mode = TG3_DEF_TX_MODE;
tp->irq_sync = 1;
+ tp->pcierr_recovery = false;
if (tg3_debug > 0)
tp->msg_enable = tg3_debug;
@@ -18071,6 +18078,8 @@ static pci_ers_result_t tg3_io_error_detected(struct pci_dev *pdev,
rtnl_lock();
+ tp->pcierr_recovery = true;
+
/* We probably don't have netdev yet */
if (!netdev || !netif_running(netdev))
goto done;
@@ -18195,6 +18204,7 @@ static void tg3_io_resume(struct pci_dev *pdev)
tg3_phy_start(tp);
done:
+ tp->pcierr_recovery = false;
rtnl_unlock();
}
diff --git a/drivers/net/ethernet/broadcom/tg3.h b/drivers/net/ethernet/broadcom/tg3.h
index 461acca..31c9f82 100644
--- a/drivers/net/ethernet/broadcom/tg3.h
+++ b/drivers/net/ethernet/broadcom/tg3.h
@@ -3407,6 +3407,7 @@ struct tg3 {
struct device *hwmon_dev;
bool link_up;
+ bool pcierr_recovery;
};
/* Accessor macros for chip and asic attributes
--
1.8.5.5
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH net] tg3: prevent ifup/ifdown during PCI error recovery
2014-08-27 13:01 [PATCH net] tg3: prevent ifup/ifdown during PCI error recovery Ivan Vecera
@ 2014-08-28 23:28 ` Prashant
2014-09-01 12:22 ` Ivan Vecera
0 siblings, 1 reply; 3+ messages in thread
From: Prashant @ 2014-08-28 23:28 UTC (permalink / raw)
To: Ivan Vecera, netdev; +Cc: Michael Chan
Ivan, thanks for the patch. Minor comments.
>
> diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
> index 3ac5d23..8d9c774 100644
> --- a/drivers/net/ethernet/broadcom/tg3.c
> +++ b/drivers/net/ethernet/broadcom/tg3.c
> @@ -11617,6 +11617,9 @@ static int tg3_open(struct net_device *dev)
> struct tg3 *tp = netdev_priv(dev);
> int err;
>
> + if (tp->pcierr_recovery)
> + return -EAGAIN;
> +
Can have a netdev_err message here indicating the pcie error recovery
that is taking place before returning.
> if (tp->fw_needed) {
> err = tg3_request_firmware(tp);
> if (tg3_asic_rev(tp) == ASIC_REV_57766) {
> @@ -11674,6 +11677,9 @@ static int tg3_close(struct net_device *dev)
> {
> struct tg3 *tp = netdev_priv(dev);
>
> + if (tp->pcierr_recovery)
> + return -EAGAIN;
> +
netdev_err message here too.
> tg3_ptp_fini(tp);
>
> tg3_stop(tp);
> @@ -17561,6 +17567,7 @@ static int tg3_init_one(struct pci_dev *pdev,
> tp->rx_mode = TG3_DEF_RX_MODE;
> tp->tx_mode = TG3_DEF_TX_MODE;
> tp->irq_sync = 1;
> + tp->pcierr_recovery = false;
>
> if (tg3_debug > 0)
> tp->msg_enable = tg3_debug;
> @@ -18071,6 +18078,8 @@ static pci_ers_result_t tg3_io_error_detected(struct pci_dev *pdev,
>
> rtnl_lock();
>
> + tp->pcierr_recovery = true;
> +
> /* We probably don't have netdev yet */
> if (!netdev || !netif_running(netdev))
> goto done;
> @@ -18195,6 +18204,7 @@ static void tg3_io_resume(struct pci_dev *pdev)
> tg3_phy_start(tp);
>
> done:
> + tp->pcierr_recovery = false;
> rtnl_unlock();
> }
>
> diff --git a/drivers/net/ethernet/broadcom/tg3.h b/drivers/net/ethernet/broadcom/tg3.h
> index 461acca..31c9f82 100644
> --- a/drivers/net/ethernet/broadcom/tg3.h
> +++ b/drivers/net/ethernet/broadcom/tg3.h
> @@ -3407,6 +3407,7 @@ struct tg3 {
>
> struct device *hwmon_dev;
> bool link_up;
> + bool pcierr_recovery;
> };
>
> /* Accessor macros for chip and asic attributes
>
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH net] tg3: prevent ifup/ifdown during PCI error recovery
2014-08-28 23:28 ` Prashant
@ 2014-09-01 12:22 ` Ivan Vecera
0 siblings, 0 replies; 3+ messages in thread
From: Ivan Vecera @ 2014-09-01 12:22 UTC (permalink / raw)
To: Prashant, netdev; +Cc: Michael Chan
On 29.8.2014 01:28, Prashant wrote:
> Ivan, thanks for the patch. Minor comments.
>
>>
>> diff --git a/drivers/net/ethernet/broadcom/tg3.c
>> b/drivers/net/ethernet/broadcom/tg3.c
>> index 3ac5d23..8d9c774 100644
>> --- a/drivers/net/ethernet/broadcom/tg3.c
>> +++ b/drivers/net/ethernet/broadcom/tg3.c
>> @@ -11617,6 +11617,9 @@ static int tg3_open(struct net_device *dev)
>> struct tg3 *tp = netdev_priv(dev);
>> int err;
>>
>> + if (tp->pcierr_recovery)
>> + return -EAGAIN;
>> +
>
> Can have a netdev_err message here indicating the pcie error recovery
> that is taking place before returning.
Sure, done. V2 sent.
Ivan
>
>> if (tp->fw_needed) {
>> err = tg3_request_firmware(tp);
>> if (tg3_asic_rev(tp) == ASIC_REV_57766) {
>> @@ -11674,6 +11677,9 @@ static int tg3_close(struct net_device *dev)
>> {
>> struct tg3 *tp = netdev_priv(dev);
>>
>> + if (tp->pcierr_recovery)
>> + return -EAGAIN;
>> +
>
> netdev_err message here too.
>
>> tg3_ptp_fini(tp);
>>
>> tg3_stop(tp);
>> @@ -17561,6 +17567,7 @@ static int tg3_init_one(struct pci_dev *pdev,
>> tp->rx_mode = TG3_DEF_RX_MODE;
>> tp->tx_mode = TG3_DEF_TX_MODE;
>> tp->irq_sync = 1;
>> + tp->pcierr_recovery = false;
>>
>> if (tg3_debug > 0)
>> tp->msg_enable = tg3_debug;
>> @@ -18071,6 +18078,8 @@ static pci_ers_result_t
>> tg3_io_error_detected(struct pci_dev *pdev,
>>
>> rtnl_lock();
>>
>> + tp->pcierr_recovery = true;
>> +
>> /* We probably don't have netdev yet */
>> if (!netdev || !netif_running(netdev))
>> goto done;
>> @@ -18195,6 +18204,7 @@ static void tg3_io_resume(struct pci_dev *pdev)
>> tg3_phy_start(tp);
>>
>> done:
>> + tp->pcierr_recovery = false;
>> rtnl_unlock();
>> }
>>
>> diff --git a/drivers/net/ethernet/broadcom/tg3.h
>> b/drivers/net/ethernet/broadcom/tg3.h
>> index 461acca..31c9f82 100644
>> --- a/drivers/net/ethernet/broadcom/tg3.h
>> +++ b/drivers/net/ethernet/broadcom/tg3.h
>> @@ -3407,6 +3407,7 @@ struct tg3 {
>>
>> struct device *hwmon_dev;
>> bool link_up;
>> + bool pcierr_recovery;
>> };
>>
>> /* Accessor macros for chip and asic attributes
>>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2014-09-01 12:21 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-08-27 13:01 [PATCH net] tg3: prevent ifup/ifdown during PCI error recovery Ivan Vecera
2014-08-28 23:28 ` Prashant
2014-09-01 12:22 ` Ivan Vecera
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).