The following patch fixes an issue with the ldmvsw driver where
the network connection of a guest domain becomes non-functional after
the guest domain has panic'd and rebooted.
The root cause was determined to be from the following series of
events:
1. Guest domain panics - resulting in the guest no longer processing
network packets (from ldmvsw driver)
2. The ldmvsw driver (in the control domain) eventually exerts flow
control due to no more available tx drings and stops the tx queue
for the guest domain
3. The LDC of the network connection for the guest is reset when
the guest domain reboots after the panic.
4. The LDC reset event is received by the ldmvsw driver and the ldmvsw
responds by clearing the tx queue for the guest.
5. ldmvsw waits indefinitely for a DATA ACK from the guest - which is
the normal method to re-enable the tx queue. But the ACK never comes
because the tx queue was cleared due to the LDC reset.
To fix this issue, in addition to clearing the tx queue, re-enable the
tx queue on a LDC reset. This prevents the ldmvsw from getting caught in
this deadlocked state of waiting for a DATA ACK which will never come.
Signed-off-by: Aaron Young <Aaron.Young@oracle.com>
Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
cassini: min_mtu 60, max_mtu 9000
niu: min_mtu 68, max_mtu 9216
sungem: min_mtu 68, max_mtu 1500 (comments say jumbo mode is broken)
sunvnet: min_mtu 68, max_mtu 65535
- removed sunvnet_change_mut_common as it does nothing now
CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Checkpatch updates for sunvnet.c and sunvnet_common.c.
Signed-off-by: Aaron Young <aaron.young@oracle.com>
Signed-off-by: Rashmi Narasimhan <rashmi.narasimhan@oracle.com>
Reviewed-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Reviewed-by: Alexandre Chartre <Alexandre.Chartre@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Modify sunvnet common code and data structures to be compatible
with both sunvnet and ldmvsw drivers.
Details:
Sunvnet operates on "vnet-port" nodes which appear in the Machine
Description (MD) in a guest domain. Ldmvsw operates on "vsw-port"
nodes which appear in the MD of a service domain.
A difference between the sunvnet driver and the ldmvsw driver is
the sunvnet driver creates a network interface (i.e. a struct net_device)
for every vnet-port *parent* "network" node. Several vnet-ports may appear
under this common parent network node - each corresponding to a common parent
network interface. Conversely, since bridge/vswitch software will need
to interface with every vsw-port in a system, the ldmvsw driver creates
a network interface (i.e. a struct net_device) for every vsw-port - not
every parent node as with sunvnet. This difference required some special
handling in the common code as explained below.
There are 2 key data structures used by the sunvnet and ldmvsw drivers
(which are now found in sunvnet_common.h):
1. struct vnet_port
This structure represents a vnet-port node in sunvnet and a vsw-port
in the ldmvsw driver.
2. struct vnet
This structure represents a parent "network" node in sunvnet and a parent
"virtual-network-switch" node in ldmvsw.
Since the sunvnet driver allocates a net_device for every parent "network"
node, a net_device member appears in the struct vnet. Since the ldmvsw
driver allocates a net_device for every port, a net_device member was
added to the vnet_port. The common code distinguishes which structure
net_device member to use by checking a 'vsw' bit that was added to the
vnet_port structure. See the VNET_PORT_TO_NET_DEVICE() marco in
sunvnet_common.h.
The netdev_priv() in sunvnet is allocated as a vnet. The netdev_priv()
in ldmvsw is a vnet_port. Therefore, any place in the common code
where a netdev_priv() call was made, a wrapper function was implemented
in each driver to first get the vnet and/or vnet_port (in a driver
specific way) and pass them as newly added parameters to the common
functions (see wrapper funcs: vnet_set_rx_mode() and vnet_poll_controller()).
Since these wrapper functions call __tx_port_find(), __tx_port_find() was
moved from the common code back into sunvnet.c. Note - ldmvsw.c does not
require this function.
These changes also required that port_is_up() be made
into a common function and thus it was given a _common suffix and
exported like the other common functions.
A wrapper function was also added for vnet_start_xmit_common() to pass a
driver-specific function arg to return the port associated with a given
struct sk_buff and struct net_device. This was required because
vnet_start_xmit_common() grabs a lock prior to getting the associated
port. Using a function pointer arg allowed the code to work unchanged
without risking changes to the non-trivial locking logic in
vnet_start_xmit_common().
Signed-off-by: Aaron Young <aaron.young@oracle.com>
Signed-off-by: Rashmi Narasimhan <rashmi.narasimhan@oracle.com>
Reviewed-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Reviewed-by: Alexandre Chartre <Alexandre.Chartre@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Split sunvnet.c into sunvnet.c and sunvnet_common.c.
Details:
Since the sunvnet and ldmvsw drivers will both use common sunvnet code,
move the functions (and support functions) anticipated to be common code
from sunvnet.c to sunvnet_common.c. Similarly, sunvnet.h was renamed to
sunvnet_common.h. The sunvnet_common.c code will be compiled into the
kernel and act as a library of functions that are linked by either
(or both) drivers when loaded.
Function names for external functions in sunvnet_common.c (to be
called by both the sunvnet and ldmvsw drivers) were tagged with a "_common"
suffix to clearly designate them as common functions.
No functional changes as of yet... just moved code verbatim to the new
sunvnet_common.c/h files.
Makefile/Kconfig support added to build sunvnet_common.c file. The code
is included in the kernel if SUN_LDOMS is defined/selected.
NOTE - per the SubmittingPatches documentation, since the code was just
moved from one file another, the code was NOT checkpatch'd in this commit
to aid in review.
Signed-off-by: Aaron Young <aaron.young@oracle.com>
Signed-off-by: Rashmi Narasimhan <rashmi.narasimhan@oracle.com>
Reviewed-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Reviewed-by: Alexandre Chartre <Alexandre.Chartre@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
