On 2019/07/18 10:23, Florian Fainelli wrote:
> On 7/17/19 6:42 PM, Benjamin Poirier wrote:
> > As pointed out by Firo Yang, a netdev tx timeout may trigger just before an
> > ethtool set_channels operation is started. be_tx_timeout(), which dumps
> > some queue structures, is not written to run concurrently with
> > be_update_queues(), which frees/allocates those queues structures. Add some
> > synchronization between the two.
> >
> > Message-id:
> > <ch2pr18mb31898e033896f9760d36bff288...@ch2pr18mb3189.namprd18.prod.outlook.com>
> > Signed-off-by: Benjamin Poirier <bpoir...@suse.com>
>
> Would not moving the netif_tx_disable() in be_close() further up in the
> function resolve that problem as well?
Thanks for your review Florian,
No, netif_tx_disable() doesn't provide mutual exclusion with
dev_watchdog(). You can have:
cpu0 cpu1
\ dev_watchdog
\ netif_tx_lock
\ be_tx_timeout
...
\ be_set_channels
\ be_update_queues
\ netif_carrier_off
\ netif_tx_disable
...
\ be_clear_queues
still running in
be_tx_timeout(),
boom!
