Commit Graph

520248 Commits

Author SHA1 Message Date
Thomas Hellstrom
15397f153c Input: joydev - don't classify the vmmouse as a joystick
Joydev is currently thinking some absolute mice are joystick, and that
messes up games in VMware guests, as the cursor typically gets stuck in
the top left corner.

Try to detect the event signature of a VMmouse input device and back off
for such devices. We're still incorrectly detecting, for example, the
VMware absolute USB mouse as a joystick, but adding an event signature
matching also that device would be considerably more risky, so defer that
to a later merge window.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-05-21 15:58:27 -07:00
David S. Miller
b66ba8d5a4 Merge branch 'stmmac-probe-refactoring'
Joachim Eastwood says:

====================
stmmac: probe code refactoring and clean up part 1

This patch set refactor the code in stmmac_pci_probe and stmmac_pltfr_probe
and moves the common bits into stmmac_dvr_probe. Along the way some clean-
ups are applied to stmmac_pltfr_probe.

The code has been tested on the LPC18xx platform.

I am still working on more refactoring of the platform probe code, hence
part 1, but I need some more time on this.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:57:26 -04:00
Joachim Eastwood
def5cd3cfd stmmac: drop unnecessary dt checks in stmmac_probe_config_dt
Since the caller already check the presence of a of_node there
is no need to repeat the check in stmmac_probe_config_dt.

There is also no point in checking the return value of the
of_match_device function since if there wasn't match in the
first place we would never be in this function.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:57:26 -04:00
Joachim Eastwood
15ffac73bb stmmac: change the stmmac_dvr_probe return type to int
Since stmmac_dvr_probe takes care of setting driver data and
assign resources to the priv structure there is no need to
access the priv structure from the other probe functions.
This mean that this function can be changed into just return
an int and thus simplifying the callers.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:57:26 -04:00
Joachim Eastwood
e56788cf13 stmmac: let stmmac_dvr_probe take a struct of resources
Creat a struct that contain all the resources that needs to be
assigned to the priv struct in stmmac_dvr_probe. This makes it
possible to factor out more common code from the other probe
functions and also use this struct to hold the resources as
they are fetched.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:57:26 -04:00
Joachim Eastwood
803f8fc462 stmmac: move driver data setting into stmmac_dvr_probe
Move setting of driver data into stmmac_dvr_probe so the
other probe functions don't have to. This will help to
simplify the other probe functions later.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:57:26 -04:00
David S. Miller
614919c3d9 Merge branch 'tcp_src_port_selection'
Eric Dumazet says:

====================
tcp: improve source port selection

With increase of TCP sockets in hosts, we often hit limitations
caused by port selection, due to randomization and poor strategy.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:55:32 -04:00
Eric Dumazet
946f9eb226 tcp: improve REUSEADDR/NOREUSEADDR cohabitation
inet_csk_get_port() randomization effort tends to spread
sockets on all the available range (ip_local_port_range)

This is unfortunate because SO_REUSEADDR sockets have
less requirements than non SO_REUSEADDR ones.

If an application uses SO_REUSEADDR hint, it is to try to
allow source ports being shared.

So instead of picking a random port number in ip_local_port_range,
lets try first in first half of the range.

This gives more chances to use upper half of the range for the
sockets with strong requirements (not using SO_REUSEADDR)

Note this patch does not add a new sysctl, and only changes
the way we try to pick port number.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Marcelo Ricardo Leitner <mleitner@redhat.com>
Cc: Flavio Leitner <fbl@redhat.com>
Acked-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:55:32 -04:00
Eric Dumazet
f5af1f57a2 inet_hashinfo: remove bsocket counter
We no longer need bsocket atomic counter, as inet_csk_get_port()
calls bind_conflict() regardless of its value, after commit
2b05ad33e1 ("tcp: bind() fix autoselection to share ports")

This patch removes overhead of maintaining this counter and
double inet_csk_get_port() calls under pressure.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Marcelo Ricardo Leitner <mleitner@redhat.com>
Cc: Flavio Leitner <fbl@redhat.com>
Acked-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:55:32 -04:00
Jason Baron
ce5ec44099 tcp: ensure epoll edge trigger wakeup when write queue is empty
We currently rely on the setting of SOCK_NOSPACE in the write()
path to ensure that we wake up any epoll edge trigger waiters when
acks return to free space in the write queue. However, if we fail
to allocate even a single skb in the write queue, we could end up
waiting indefinitely.

Fix this by explicitly issuing a wakeup when we detect the condition
of an empty write queue and a return value of -EAGAIN. This allows
userspace to re-try as we expect this to be a temporary failure.

I've tested this approach by artificially making
sk_stream_alloc_skb() return NULL periodically. In that case,
epoll edge trigger waiters will hang indefinitely in epoll_wait()
without this patch.

Signed-off-by: Jason Baron <jbaron@akamai.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:52:47 -04:00
Daniel Borkmann
c78e1746d3 net: sched: fix call_rcu() race on classifier module unloads
Vijay reported that a loop as simple as ...

  while true; do
    tc qdisc add dev foo root handle 1: prio
    tc filter add dev foo parent 1: u32 match u32 0 0  flowid 1
    tc qdisc del dev foo root
    rmmod cls_u32
  done

... will panic the kernel. Moreover, he bisected the change
apparently introducing it to 78fd1d0ab0 ("netlink: Re-add
locking to netlink_lookup() and seq walker").

The removal of synchronize_net() from the netlink socket
triggering the qdisc to be removed, seems to have uncovered
an RCU resp. module reference count race from the tc API.
Given that RCU conversion was done after e341694e3e ("netlink:
Convert netlink_lookup() to use RCU protected hash table")
which added the synchronize_net() originally, occasion of
hitting the bug was less likely (not impossible though):

When qdiscs that i) support attaching classifiers and,
ii) have at least one of them attached, get deleted, they
invoke tcf_destroy_chain(), and thus call into ->destroy()
handler from a classifier module.

After RCU conversion, all classifier that have an internal
prio list, unlink them and initiate freeing via call_rcu()
deferral.

Meanhile, tcf_destroy() releases already reference to the
tp->ops->owner module before the queued RCU callback handler
has been invoked.

Subsequent rmmod on the classifier module is then not prevented
since all module references are already dropped.

By the time, the kernel invokes the RCU callback handler from
the module, that function address is then invalid.

One way to fix it would be to add an rcu_barrier() to
unregister_tcf_proto_ops() to wait for all pending call_rcu()s
to complete.

synchronize_rcu() is not appropriate as under heavy RCU
callback load, registered call_rcu()s could be deferred
longer than a grace period. In case we don't have any pending
call_rcu()s, the barrier is allowed to return immediately.

Since we came here via unregister_tcf_proto_ops(), there
are no users of a given classifier anymore. Further nested
call_rcu()s pointing into the module space are not being
done anywhere.

Only cls_bpf_delete_prog() may schedule a work item, to
unlock pages eventually, but that is not in the range/context
of cls_bpf anymore.

Fixes: 25d8c0d55f ("net: rcu-ify tcf_proto")
Fixes: 9888faefe1 ("net: sched: cls_basic use RCU")
Reported-by: Vijay Subramanian <subramanian.vijay@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:48:18 -04:00
David S. Miller
b92d581499 Merge branch 'cxgb4-next'
Hariprasad Shenai says:

====================
cxgb4: Cleanup and update T4/T4 register ranges

This series cleans and optimizes setup_memwin function and also updates
T4/T5 adapter register ranges by removing incorrect register addresses

This patch series has been created against net-next tree and includes
patches on cxgb4 driver.

We have included all the maintainers of respective drivers. Kindly review
the change and let us know in case of any review comments.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:46:36 -04:00
Hariprasad Shenai
9f5ac48de3 cxgb4: Update T4/T5 adapter register ranges
Remove some T4/T5 registers that were included incorrectly.

Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:46:36 -04:00
Hariprasad Shenai
b562fc3713 cxgb4: Optimize and cleanup setup memory window code
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:46:36 -04:00
David S. Miller
4e7b3be406 Merge branch 'sfc-next'
Shradha Shah says:

====================
sfc: Get/Set MAC address and ndo_[set/get]_vf_* entrypoint functions

This is the second installment of patches towards supporting EF10 SRIOV.

This patch series implements the ndo_get_vf_config, ndo_set_vf_mac,
ndo_set_vf_vlan and ndo_set_vf_spoofcheck function callbacks for EF10.

This patch series also introduces privileges for the MCDI commands
based on which functions are allowed to call them, i.e. Link control
or primary function.

The patch series has been tested with and without CONFIG_SFC_SRIOV.

The ndo function callbacks are tested using ip link.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:55 -04:00
Shradha Shah
910c8789a7 sfc: set the MAC address using MC_CMD_VADAPTOR_SET_MAC
Add a set_mac_address() NIC-type function for EF10 only, and
use this to set the MAC address on the vadaptor. For Siena and
earlier, the MAC address continues to be set by MC_CMD_SET_MAC;
this is still called on EF10, and including a MAC address in
this command has no effect.

The sriov_mac_address_changed() NIC-type function is no longer
needed on EF10, but it is needed for Siena where it is used to
update the peer address of the PF for VFDI.  Change this to use
the new set_mac_address function pointer.

efx_ef10_sriov_mac_address_changed() is no longer called, as VFs
will try to change the MAC address on their vadaptor rather than
trying to change to the context of the PF to alter the vport.

When a VF is running in direct passthrough mode with MAC spoofing
enabled, it will be able to change the MAC address on its vadaptor.
In this case, there is a link to the PF, so find the correct VF in
its ef10_vf array and update the MAC address.

ndo_set_mac_address() can be called during driver unload while
bonding, and in this case the device has already been stopped, so
don't call efx_net_open() to restart it after reconfiguration.

efx->port_enabled is set to false in efx_stop_port(), so it is
indicator of whether the device needs to be restarted.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:55 -04:00
Shradha Shah
860d2ffa75 sfc: Implement dummy disable of VF spoof check for EF10
Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:55 -04:00
Edward Cree
4392dc6900 sfc: add ndo_set_vf_link_state() function for EF10
Exercised with
"ip link set <PF intf> vf <vf_i> state {auto|enable|disable}"
Sets the reporting policy for VF link state to either
 - mirror physical link state
 - always up
 - always down

get VF link state mode in efx_ef10_sriov_get_vf_config

Exercised by
"ip link show <PF intf>";
output will include a line like
vf 0 MAC 12:34:56:78:9a:bc, link-state auto

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:54 -04:00
Shradha Shah
2d432f20d2 sfc: add ndo_set_vf_vlan() function for EF10
The max vlan tags that can be offloaded is 2, including any upstream VLAN
aggregator. Currently there is no way for the net driver to know whether
the upstream vswitch (if any) is using vlan tags, so there is no way to
know how many tags we can request.
Along with the implementation for the ndo_set_vf_vlan callback, this patch
also adds 2 VLAN tags for the driver created VEB switch if possible, that
way it is possible to offload as many tags as are allowed.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:54 -04:00
Jon Cooper
087e902550 sfc: Change entity reset on MC reboot to a new datapath-only reset.
Currently we do an entity reset when we detect an MC reboot.
This messes up SRIOV because it leaves VFs orphaned. The extra
reset is rather redundant anyway, since the MC reboot will have
basically reset everything.

This change replaces the entity reset after MC reboot with a
simpler datapath reset that reallocates resources but doesn't
perform the entity reset.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:54 -04:00
Shradha Shah
b9af90499a sfc: Add ndo_get_vf_config() function for EF10
rtnetlink calls ndo_get_vf_config when compiling information
about a network interface, so that the VFs associated with a PF
can be listed (eg: ip link show).
Implement a response to this entry point and return PF-set MAC
address for VF in ndo_get_vf_config

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:54 -04:00
Shradha Shah
e340be9230 sfc: add ndo_set_vf_mac() function for EF10
Implement a response to this entrypoint.
The ndo_set_vf_mac() entrypoint is only exposed in the driver if
CONFIG_SFC_SRIOV is defined.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:54 -04:00
Jon Cooper
aa09a3da70 sfc: Initialise MCDI buffers to 0 on declaration.
In order to avoid MC bugs the flags field needs to be set to 0.
Instead of explicitly clearing out the flags individually, a
better way to do this is to memset the MCDI_BUF to 0.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:53 -04:00
Daniel Pieczko
0d5e0fbba0 sfc: Enable a VF to get its own MAC address
A VF's MAC address is set by its parent PF and added to its vport.
To get this MAC address, the VF must use MC_CMD_ VPORT_GET_MAC_ADDRESSES.
In the current scheme, a VF's vport should only have one MAC address,
so warn if this is not the case.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:53 -04:00
Edward Cree
0d322413d6 sfc: protect filter table against use-after-free
If MCDI timeouts are encountered during efx_ef10_filter_table_remove(),
an FLR will be queued, but efx->filter_state will still be kfree()d.
The queued FLR will then call efx_ef10_filter_table_restore(), which
will try to use efx->filter_state. This previously caused a panic.
This patch adds an rwsem to protect the existence of efx->filter_state,
separately from the spinlock protecting its contents.  Users which can
race against efx_ef10_filter_table_remove() should down_read this rwsem.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:53 -04:00
Shradha Shah
f1122a345b sfc: Store the efx_nic struct of the current VF in the VF data struct
Initialised in efx_probe_vf and removal is dealt with in
efx_ef10_remove.

vf->efx is needed in future patches to change the MAC address
of the VF via the parent PF, while the driver is bound to the
VF.
Example: ip link set dev vf NUM mac LLADDR

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:53 -04:00
Shradha Shah
cfc77c2fba sfc: save old MAC address in case sriov_mac_address_changed fails
Otherwise the PF and VF can disagree on the VF's MAC address and
this leads to strange behaviour, up to and including kernel panics.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:53 -04:00
Shradha Shah
88a37de674 sfc: Store vf_index in nic_data for Ef10.
Added function efx_ef10_get_vf_index to store the vf_index
in nic_data during probe

vf_index is needed in future patches to access a particular
VF in the VF data structure.

Moved efx_ef10_probe_pf and efx_ef10_probe_vf in order to
used efx_ef10_remove

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:52 -04:00
Shradha Shah
862f894cb9 sfc: MC_CMD_SET_MAC can only be called by the link control Function
MC_CMD_SET_MAC is privileged and can only by called by the link
control function.

This patch adds efx_ef10_mac_reconfigure_vf which avoids the call
to MC_CMD_SET_MAC by the Virtual function

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:52 -04:00
Shradha Shah
af6a074d12 sfc: change definition of MC_CMD_VADAPTOR_ALLOC
Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:52 -04:00
Shradha Shah
75122ec8ff sfc: Add permissions to MCDI commands
There is one primary function per adaptor, one link control function
per port and the rest as categorised as general.

This patch adds privileges to the MCDI commands based on which
functions are allowed to call them.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:43:52 -04:00
Vineet Gupta
4ec49a372c stmmac: replace open coded __netdev_alloc_skb_ip_align() with actual call
This also matches with the sibling call netdev_alloc_skb_ip_align() made in
rx fast path.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 18:40:55 -04:00
Joe Perches
3f6e785fe1 qlge: Move jiffies_to_usecs immediately before loop
30 usecs (or really, 1 jiffy) can go by pretty fast.

Move the set of the timeout immediately before the loop.

Remove the unnecessary max(1ul, usecs_to_jiffies(30)) as
usecs_to_jiffies with a non-zero constant is guaranteed
to be non-zero.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:23:18 -04:00
David S. Miller
4ac2dc8928 Merge branch 'rocker-transaction-fixes'
Simon Horman says:

====================
rocker: transaction fixes

this series addresses what appear to be errors in the handling of
prepare and then commit transactions in the rocker driver.

In all cases the problem is that data structures visible outside of
the transaction are modified during the prepare phase.

In the case of the first two patches this results in the kernel reporting a
BUG. I have noted test-cases in the change logs.

The third patch is also a bug fix, as noted by  Toshiaki Makita,
however I have not been able to reliably reproduce the problem and
thus have not provided a test case.

The last patch is a correctness fix that does not fix a bug
that manifests as far as I can tell.

Changes: v3->v4
* All patches
  - Add Jiri Pirko's ack
* "rocker: do not make neighbour entry changes when preparing transactions"
  - Setting of entry values in all transaction phases
    as suggested by Toshiaki Makita
* "rocker: make rocker_port_internal_vlan_id_{get,put}() non-transactional"
  - Remove Fixes tag as I believe this is a correctness rather than a bug fix

Changes: v2->v3
* "rocker: do not make neighbour entry changes when preparing transactions"
  - Correct inverted logic
  - Added ack from Scott Feldman

Changes: v1->v2
* "rocker: do not make neighbour entry changes when preparing transactions"
  - Revised changelog to reflect information from Toshiaki Makita
    that there is a bug that can manifest
  - Update address and ttl regardless of the value of the transaction state
* All other patches
  - Added acks from Scott Feldman
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:20:55 -04:00
Simon Horman
df6a206730 rocker: make rocker_port_internal_vlan_id_{get, put}() non-transactional
The motivation for this is that rocker_port_internal_vlan_id_{get,put} appear
to only partially implement the transaction model: memory allocation
and freeing is transactional, but hash and bitmap manipulation is not.

The latter could be fixed, however, as it is not currently exercised
due to trans always being SWITCHDEV_TRANS_NONE it seems cleaner
to make rocker_port_internal_vlan_id_get non-transactional.

This problem was introduced by c4f20321d9 ("rocker: support
prepare-commit transaction model").

Found by inspection.
I do not believe that this change should have any run-time effect.

Acked-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:20:55 -04:00
Simon Horman
550ecc92fe rocker: do not make neighbour entry changes when preparing transactions
rocker_port_ipv4_nh() and in turn rocker_port_ipv4_neigh() may be
be called with trans == SWITCHDEV_TRANS_PREPARE and then
trans == SWITCHDEV_TRANS_COMMIT from switchdev_port_obj_set() via
fib_table_insert().

The first time that rocker_port_ipv4_nh() is called, with
trans == SWITCHDEV_TRANS_PREPARE, _rocker_neigh_add() adds a new entry to
the neigh table.

And the second time  rocker_port_ipv4_nh() is called, with
trans == SWITCHDEV_TRANS_COMMIT, that entry is found. This causes
rocker_port_ipv4_nh() to believe it is not adding an entry and thus it
frees "entry", which is still present in rocker driver's neigh table.

This problem does not appear to affect deletion as my analysis is that
deletion is always performed with trans == SWITCHDEV_TRANS_NONE.

For completeness _rocker_neigh_{add,del,prepare} are updated not to
manipulate fib table entries if trans == SWITCHDEV_TRANS_PREPARE.

Fixes: c4f20321d9 ("rocker: support prepare-commit transaction model")
Reported-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:20:55 -04:00
Simon Horman
42e9488971 rocker: do not modify fdb table in rocker_port_fdb() when preparing transactions
rocker_port_fdb_flush() may be called be called with
trans == SWITCHDEV_TRANS_PREPARE and then trans == SWITCHDEV_TRANS_COMMIT from
switchdev_port_attr_set() via switchdev_port_obj_add().

Adding the new entry to the FDB table when trans == SWITCHDEV_TRANS_PREPARE
may result in a memory leak because when trans == SWITCHDEV_TRANS_PREPARE
rocker_flow_tbl_bridge() will allocate memory when called via
rocker_port_fdb_learn(). However, when trans == SWITCHDEV_TRANS_COMMIT
the presence of the FDB entry in the FDB table causes
rocker_port_fdb() to set the ROCKER_OP_FLAG_REFRESH flag which results
in rocker_port_fdb_learn() skipping the call to rocker_flow_tbl_bridge()
which would free the memory allocated by it when
trans == SWITCHDEV_TRANS_PREPARE.

ip link add br0 type bridge
ip link set up dev eth0
ip link set dev eth0 master br0
bridge fdb add 52:54:00:12:35:08 dev eth0
bridge fdb add 52:54:00:12:35:09 dev eth0
[    2.600730] ------------[ cut here ]------------
[    2.601002] kernel BUG at drivers/net/ethernet/rocker/rocker.c:4369!
[    2.601373] invalid opcode: 0000 [#1] SMP
[    2.601963] Modules linked in:
[    2.602355] CPU: 0 PID: 64 Comm: bridge Not tainted 4.1.0-rc3-01048-g6d0f50c50211-dirty #1075
[    2.602721] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.0-0-g4c59f5d-20150219_092859-nilsson.home.kraxel.org 04/01/2014
[    2.602721] task: ffff880019facef0 ti: ffff88001f96c000 task.ti: ffff88001f96c000
[    2.602721] RIP: 0010:[<ffffffff811f1470>]  [<ffffffff811f1470>] rocker_port_obj_add+0x150/0x160
[    2.602721] RSP: 0018:ffff88001f96fa98  EFLAGS: 00000212
[    2.602721] RAX: ffff880019d4fa68 RBX: ffff88001f96fb18 RCX: 0000000000000000
[    2.602721] RDX: ffff880019d4f000 RSI: ffff88001f96fb18 RDI: ffff880019d4f000
[    2.602721] RBP: 0000000000000001 R08: 0000000000000000 R09: ffff88001f904620
[    2.602721] R10: ffff88001f96fb60 R11: ffff880019e9d100 R12: ffff88001f96fb18
[    2.602721] R13: ffff880019d4f680 R14: ffff88001f904610 R15: ffff8800198f7b80
[    2.602721] FS:  00007f3eee917700(0000) GS:ffff88001b000000(0000) knlGS:0000000000000000
[    2.602721] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    2.602721] CR2: 00007f3eee4a15cb CR3: 000000001f933000 CR4: 00000000000006b0
[    2.602721] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    2.602721] DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000
[    2.602721] Stack:
[    2.602721]  0000000000000000 ffff88001f96fb18 ffff880019d4f000 ffff88001f96fb18
[    2.602721]  ffff880019d4f000 ffffffff81332105 ffff88001f96fb50 ffffffff814464c0
[    2.602721]  ffff88001f96fb18 ffff88001f904600 ffff880019d4f000 ffffffff813326e5
[    2.602721] Call Trace:
[    2.602721]  [<ffffffff81332105>] ? __switchdev_port_obj_add+0x25/0x90
[    2.602721]  [<ffffffff813326e5>] ? switchdev_port_obj_add+0x25/0xc0
[    2.602721]  [<ffffffff813327b1>] ? switchdev_port_fdb_add+0x31/0x40
[    2.602721]  [<ffffffff8123911f>] ? rtnl_fdb_add+0xff/0x1e0
[    2.602721]  [<ffffffff81237d8e>] ? rtnetlink_rcv_msg+0x7e/0x250
[    2.602721]  [<ffffffff8121d1ce>] ? __skb_recv_datagram+0xfe/0x4b0
[    2.602721]  [<ffffffff81237d10>] ? rtnetlink_rcv+0x30/0x30
[    2.602721]  [<ffffffff81247958>] ? netlink_rcv_skb+0xa8/0xd0
[    2.602721]  [<ffffffff81237cff>] ? rtnetlink_rcv+0x1f/0x30
[    2.602721]  [<ffffffff81247220>] ? netlink_unicast+0x150/0x200
[    2.602721]  [<ffffffff81247714>] ? netlink_sendmsg+0x374/0x3e0
[    2.602721]  [<ffffffff8120f8df>] ? sock_sendmsg+0xf/0x30
[    2.602721]  [<ffffffff8120ffd3>] ? ___sys_sendmsg+0x1f3/0x200
[    2.602721]  [<ffffffff812100e5>] ? ___sys_recvmsg+0x105/0x140
[    2.602721]  [<ffffffff810a36f0>] ? SyS_readahead+0x90/0x90
[    2.602721]  [<ffffffff81098dfd>] ? filemap_map_pages+0x1ed/0x210
[    2.602721]  [<ffffffff810b77fc>] ? handle_mm_fault+0x5fc/0xe50
[    2.602721]  [<ffffffff81210ef9>] ? __sys_sendmsg+0x39/0x70
[    2.602721]  [<ffffffff8133ce17>] ? system_call_fastpath+0x12/0x6a
[    2.602721] Code: b7 8f a0 06 00 00 48 83 bf 88 06 00 00 00 74 1d 48 83 c4 08 89 ee 4c 89 ef 5b 5d 41 5c 41 5d 0f b7 c9 45 31 c0 e9 51 db ff ff 90 <0f> 0b b8 ea ff ff ff e9 cf fe ff ff 0f 1f 40 00 41 57 41 56 b9
[    2.602721] RIP  [<ffffffff811f1470>] rocker_port_obj_add+0x150/0x160
[    2.602721]  RSP <ffff88001f96fa98>
[    2.615848] ---[ end trace 4f7b4f1c98077108 ]---

The above is resolved by not adding the new FDB entry to the FDB table
if trans == SWITCHDEV_TRANS_PREPARE.

For symmetry this patch also skips deleting FDB entries from the FDB
table trans == SWITCHDEV_TRANS_PREPARE. However, my analysis is that
this never occurs as trans is always SWITCHDEV_TRANS_NONE when removing
FDB entries.

Fixes: c4f20321d9 ("rocker: support prepare-commit transaction model")
Acked-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:20:54 -04:00
Simon Horman
3098ac3963 rocker: do not delete fdb entries in rocker_port_fdb_flush() when preparing transactions
rocker_port_fdb_flush() is called by rocker_port_stp_update() which in
turn may be called with trans == SWITCHDEV_TRANS_PREPARE and then
trans == SWITCHDEV_TRANS_COMMIT from switchdev_port_attr_set() via
br_set_state().

When rocker_port_fdb_flush() is called with trans == SWITCHDEV_TRANS_PREPARE
it calls rocker_port_fdb_learn() for each entry in the FDB table which in
turn calls rocker_flow_tbl_bridge() which will allocate memory using
rocker_port_kzalloc(). rocker_port_fdb_learn() will then remove the entry
from the FDB table.

Then when rocker_port_fdb_learn() is called with
trans == SWITCHDEV_TRANS_PREPARE no calls are made to rocker_port_fdb_learn()
because there are no longer any entries present in the FDB table. Thus the
memory previously allocated by rocker_port_fdb_learn() is leaked resulting
in the kernel BUG() below.

Furthermore, it looks like the driver ends up with an incorrect view of the
fdb table as the FDB entries are purged from the driver's table but not the
hardware's table.

ip link add br0 type bridge
ip link set up dev eth0
sleep 1
ip link set dev eth0 master br0
[    3.704360] ------------[ cut here ]------------
[    3.704611] kernel BUG at drivers/net/ethernet/rocker/rocker.c:4289!
[    3.704962] invalid opcode: 0000 [#1] SMP
[    3.705537] Modules linked in:
[    3.705919] CPU: 0 PID: 63 Comm: ip Not tainted 4.1.0-rc3-01046-gb9fbe709de4d #1044
[    3.706191] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.0-0-g4c59f5d-20150219_092859-nilsson.home.kraxel.org 04/01/2014
[    3.706820] task: ffff880019f70150 ti: ffff88001f92c000 task.ti: ffff88001f92c000
[    3.707138] RIP: 0010:[<ffffffff811f0080>]  [<ffffffff811f0080>] rocker_port_attr_set+0xe0/0xf0
[    3.707990] RSP: 0018:ffff88001f92f808  EFLAGS: 00000212
[    3.708200] RAX: ffff880019d4fa68 RBX: ffff880019d4f000 RCX: 0000000000000000
[    3.708471] RDX: 000000000000000c RSI: ffff88001f92f890 RDI: ffff880019d4f680
[    3.708740] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000004
[    3.708999] R10: ffff880000034024 R11: 0000000000000000 R12: ffff88001f92f890
[    3.709276] R13: ffff88001f8f1c00 R14: 000000000000000b R15: 0000000000000000
[    3.709303] FS:  00007f8ab66bd700(0000) GS:ffff88001b000000(0000) knlGS:0000000000000000
[    3.709303] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    3.709303] CR2: 0000000000654988 CR3: 000000001f8f3000 CR4: 00000000000006b0
[    3.709303] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    3.709303] DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000
[    3.709303] Stack:
[    3.709303]  ffff88001f8f1c00 000000000000000b ffff88001f92f890 ffff880019d4f000
[    3.709303]  ffff88001f92f890 ffffffff813332f5 ffff88001f92f880 0000000000000000
[    3.709303]  ffff88001f92f890 0000000000000001 ffff880019d4f000 ffffffff81333627
[    3.709303] Call Trace:
[    3.709303]  [<ffffffff813332f5>] ? __switchdev_port_attr_set+0x25/0x90
[    3.709303]  [<ffffffff81333627>] ? switchdev_port_attr_set+0x27/0x120
[    3.709303]  [<ffffffff81318e86>] ? br_set_state+0x36/0x50
[    3.709303]  [<ffffffff8131795c>] ? br_add_if+0x37c/0x400
[    3.709303]  [<ffffffff81238ce1>] ? do_setlink+0x7e1/0x800
[    3.709303]  [<ffffffff8111f980>] ? radix_tree_lookup_slot+0x10/0x30
[    3.709303]  [<ffffffff81136fba>] ? nla_parse+0xaa/0x110
[    3.709303]  [<ffffffff81239c98>] ? rtnl_newlink+0x548/0x870
[    3.709303]  [<ffffffff8111f900>] ? __radix_tree_lookup+0x40/0xb0
[    3.709303]  [<ffffffff81136f3e>] ? nla_parse+0x2e/0x110
[    3.709303]  [<ffffffff81237d7e>] ? rtnetlink_rcv_msg+0x7e/0x250
[    3.709303]  [<ffffffff8121d1be>] ? __skb_recv_datagram+0xfe/0x4b0
[    3.709303]  [<ffffffff81237d00>] ? rtnetlink_rcv+0x30/0x30
[    3.709303]  [<ffffffff81247948>] ? netlink_rcv_skb+0xa8/0xd0
[    3.709303]  [<ffffffff81237cef>] ? rtnetlink_rcv+0x1f/0x30
[    3.709303]  [<ffffffff81247210>] ? netlink_unicast+0x150/0x200
[    3.709303]  [<ffffffff81247704>] ? netlink_sendmsg+0x374/0x3e0
[    3.709303]  [<ffffffff8120f8cf>] ? sock_sendmsg+0xf/0x30
[    3.709303]  [<ffffffff8120ffc3>] ? ___sys_sendmsg+0x1f3/0x200
[    3.709303]  [<ffffffff812100d5>] ? ___sys_recvmsg+0x105/0x140
[    3.709303]  [<ffffffff812228d9>] ? dev_get_by_name_rcu+0x69/0x90
[    3.709303]  [<ffffffff812228d9>] ? dev_get_by_name_rcu+0x69/0x90
[    3.709303]  [<ffffffff81217b7d>] ? skb_dequeue+0x4d/0x60
[    3.709303]  [<ffffffff81217bb0>] ? skb_queue_purge+0x20/0x30
[    3.709303]  [<ffffffff810ebdcf>] ? __inode_wait_for_writeback+0x5f/0xb0
[    3.709303]  [<ffffffff810648b0>] ? autoremove_wake_function+0x30/0x30
[    3.709303]  [<ffffffff81210ee9>] ? __sys_sendmsg+0x39/0x70
[    3.709303]  [<ffffffff8133e097>] ? system_call_fastpath+0x12/0x6a
[    3.709303] Code: bb 90 06 00 00 48 c7 04 24 00 00 00 00 45 31 c9 45 31 c0 48 c7 c1 c0 b7 1e 81 89 ea e8 da da ff ff eb 95 0f 1f 84 00 00 00 00 00 <0f> 0b 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 48 83 fe 15 75
[    3.709303] RIP  [<ffffffff811f0080>] rocker_port_attr_set+0xe0/0xf0
[    3.709303]  RSP <ffff88001f92f808>
[    3.721409] ---[ end trace b7481fcb7cb032aa ]---
Segmentation fault

Fixes: c4f20321d9 ("rocker: support prepare-commit transaction model")
Acked-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:20:54 -04:00
Joe Perches
e26cc7ff77 spider_net: Use DECLARE_BITMAP
Use the generic mechanism to declare a bitmap instead of unsigned long.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:17:50 -04:00
David S. Miller
3f55b7ed5e Merge branch 'ebpf-tail-call'
Alexei Starovoitov says:

====================
bpf: introduce bpf_tail_call() helper

introduce bpf_tail_call(ctx, &jmp_table, index) helper function
which can be used from BPF programs like:
int bpf_prog(struct pt_regs *ctx)
{
  ...
  bpf_tail_call(ctx, &jmp_table, index);
  ...
}
that is roughly equivalent to:
int bpf_prog(struct pt_regs *ctx)
{
  ...
  if (jmp_table[index])
    return (*jmp_table[index])(ctx);
  ...
}
The important detail that it's not a normal call, but a tail call.
The kernel stack is precious, so this helper reuses the current
stack frame and jumps into another BPF program without adding
extra call frame.
It's trivially done in interpreter and a bit trickier in JITs.

Use cases:
- simplify complex programs
- dispatch into other programs
  (for example: index in jump table can be syscall number or network protocol)
- build dynamic chains of programs

The chain of tail calls can form unpredictable dynamic loops therefore
tail_call_cnt is used to limit the number of calls and currently is set to 32.

patch 1 - support bpf_tail_call() in interpreter
patch 2 - support in x64 JIT
We've discussed what's neccessary to support it in arm64/s390 JITs
and it looks fine.
patch 3 - sample example for tracing
patch 4 - sample example for networking

More details in every patch.

This set went through several iterations of reviews/fixes and older
attempts can be seen:
https://git.kernel.org/cgit/linux/kernel/git/ast/bpf.git/log/?h=tail_call_v[123456]
- tail_call_v1 does it without touching JITs but introduces overhead
  for all programs that don't use this helper function.
- tail_call_v2 still has some overhead and x64 JIT does full stack
  unwind (prologue skipping optimization wasn't there)
- tail_call_v3 reuses 'call' instruction encoding and has interpreter
  overhead for every normal call
- tail_call_v4 fixes above architectural shortcomings and v5,v6 fix few
  more bugs

This last tail_call_v6 approach seems to be the best.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:08:00 -04:00
Alexei Starovoitov
530b2c8619 samples/bpf: bpf_tail_call example for networking
Usage:
$ sudo ./sockex3
IP     src.port -> dst.port               bytes      packets
127.0.0.1.42010 -> 127.0.0.1.12865         1568            8
127.0.0.1.59526 -> 127.0.0.1.33778     11422636       173070
127.0.0.1.33778 -> 127.0.0.1.59526  11260224828       341974
127.0.0.1.12865 -> 127.0.0.1.42010         1832           12
IP     src.port -> dst.port               bytes      packets
127.0.0.1.42010 -> 127.0.0.1.12865         1568            8
127.0.0.1.59526 -> 127.0.0.1.33778     23198092       351486
127.0.0.1.33778 -> 127.0.0.1.59526  22972698518       698616
127.0.0.1.12865 -> 127.0.0.1.42010         1832           12

this example is similar to sockex2 in a way that it accumulates per-flow
statistics, but it does packet parsing differently.
sockex2 inlines full packet parser routine into single bpf program.
This sockex3 example have 4 independent programs that parse vlan, mpls, ip, ipv6
and one main program that starts the process.
bpf_tail_call() mechanism allows each program to be small and be called
on demand potentially multiple times, so that many vlan, mpls, ip in ip,
gre encapsulations can be parsed. These and other protocol parsers can
be added or removed at runtime. TLVs can be parsed in similar manner.
Note, tail_call_cnt dynamic check limits the number of tail calls to 32.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:07:59 -04:00
Alexei Starovoitov
5bacd7805a samples/bpf: bpf_tail_call example for tracing
kprobe example that demonstrates how future seccomp programs may look like.
It attaches to seccomp_phase1() function and tail-calls other BPF programs
depending on syscall number.

Existing optimized classic BPF seccomp programs generated by Chrome look like:
if (sd.nr < 121) {
  if (sd.nr < 57) {
    if (sd.nr < 22) {
      if (sd.nr < 7) {
        if (sd.nr < 4) {
          if (sd.nr < 1) {
            check sys_read
          } else {
            if (sd.nr < 3) {
              check sys_write and sys_open
            } else {
              check sys_close
            }
          }
        } else {
      } else {
    } else {
  } else {
} else {
}

the future seccomp using native eBPF may look like:
  bpf_tail_call(&sd, &syscall_jmp_table, sd.nr);
which is simpler, faster and leaves more room for per-syscall checks.

Usage:
$ sudo ./tracex5
<...>-366   [001] d...     4.870033: : read(fd=1, buf=00007f6d5bebf000, size=771)
<...>-369   [003] d...     4.870066: : mmap
<...>-369   [003] d...     4.870077: : syscall=110 (one of get/set uid/pid/gid)
<...>-369   [003] d...     4.870089: : syscall=107 (one of get/set uid/pid/gid)
   sh-369   [000] d...     4.891740: : read(fd=0, buf=00000000023d1000, size=512)
   sh-369   [000] d...     4.891747: : write(fd=1, buf=00000000023d3000, size=512)
   sh-369   [000] d...     4.891747: : read(fd=1, buf=00000000023d3000, size=512)

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:07:59 -04:00
Alexei Starovoitov
b52f00e6a7 x86: bpf_jit: implement bpf_tail_call() helper
bpf_tail_call() arguments:
ctx - context pointer
jmp_table - one of BPF_MAP_TYPE_PROG_ARRAY maps used as the jump table
index - index in the jump table

In this implementation x64 JIT bypasses stack unwind and jumps into the
callee program after prologue, so the callee program reuses the same stack.

The logic can be roughly expressed in C like:

u32 tail_call_cnt;

void *jumptable[2] = { &&label1, &&label2 };

int bpf_prog1(void *ctx)
{
label1:
    ...
}

int bpf_prog2(void *ctx)
{
label2:
    ...
}

int bpf_prog1(void *ctx)
{
    ...
    if (tail_call_cnt++ < MAX_TAIL_CALL_CNT)
        goto *jumptable[index]; ... and pass my 'ctx' to callee ...

    ... fall through if no entry in jumptable ...
}

Note that 'skip current program epilogue and next program prologue' is
an optimization. Other JITs don't have to do it the same way.
>From safety point of view it's valid as well, since programs always
initialize the stack before use, so any residue in the stack left by
the current program is not going be read. The same verifier checks are
done for the calls from the kernel into all bpf programs.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:07:59 -04:00
Alexei Starovoitov
04fd61ab36 bpf: allow bpf programs to tail-call other bpf programs
introduce bpf_tail_call(ctx, &jmp_table, index) helper function
which can be used from BPF programs like:
int bpf_prog(struct pt_regs *ctx)
{
  ...
  bpf_tail_call(ctx, &jmp_table, index);
  ...
}
that is roughly equivalent to:
int bpf_prog(struct pt_regs *ctx)
{
  ...
  if (jmp_table[index])
    return (*jmp_table[index])(ctx);
  ...
}
The important detail that it's not a normal call, but a tail call.
The kernel stack is precious, so this helper reuses the current
stack frame and jumps into another BPF program without adding
extra call frame.
It's trivially done in interpreter and a bit trickier in JITs.
In case of x64 JIT the bigger part of generated assembler prologue
is common for all programs, so it is simply skipped while jumping.
Other JITs can do similar prologue-skipping optimization or
do stack unwind before jumping into the next program.

bpf_tail_call() arguments:
ctx - context pointer
jmp_table - one of BPF_MAP_TYPE_PROG_ARRAY maps used as the jump table
index - index in the jump table

Since all BPF programs are idenitified by file descriptor, user space
need to populate the jmp_table with FDs of other BPF programs.
If jmp_table[index] is empty the bpf_tail_call() doesn't jump anywhere
and program execution continues as normal.

New BPF_MAP_TYPE_PROG_ARRAY map type is introduced so that user space can
populate this jmp_table array with FDs of other bpf programs.
Programs can share the same jmp_table array or use multiple jmp_tables.

The chain of tail calls can form unpredictable dynamic loops therefore
tail_call_cnt is used to limit the number of calls and currently is set to 32.

Use cases:
Acked-by: Daniel Borkmann <daniel@iogearbox.net>

==========
- simplify complex programs by splitting them into a sequence of small programs

- dispatch routine
  For tracing and future seccomp the program may be triggered on all system
  calls, but processing of syscall arguments will be different. It's more
  efficient to implement them as:
  int syscall_entry(struct seccomp_data *ctx)
  {
     bpf_tail_call(ctx, &syscall_jmp_table, ctx->nr /* syscall number */);
     ... default: process unknown syscall ...
  }
  int sys_write_event(struct seccomp_data *ctx) {...}
  int sys_read_event(struct seccomp_data *ctx) {...}
  syscall_jmp_table[__NR_write] = sys_write_event;
  syscall_jmp_table[__NR_read] = sys_read_event;

  For networking the program may call into different parsers depending on
  packet format, like:
  int packet_parser(struct __sk_buff *skb)
  {
     ... parse L2, L3 here ...
     __u8 ipproto = load_byte(skb, ... offsetof(struct iphdr, protocol));
     bpf_tail_call(skb, &ipproto_jmp_table, ipproto);
     ... default: process unknown protocol ...
  }
  int parse_tcp(struct __sk_buff *skb) {...}
  int parse_udp(struct __sk_buff *skb) {...}
  ipproto_jmp_table[IPPROTO_TCP] = parse_tcp;
  ipproto_jmp_table[IPPROTO_UDP] = parse_udp;

- for TC use case, bpf_tail_call() allows to implement reclassify-like logic

- bpf_map_update_elem/delete calls into BPF_MAP_TYPE_PROG_ARRAY jump table
  are atomic, so user space can build chains of BPF programs on the fly

Implementation details:
=======================
- high performance of bpf_tail_call() is the goal.
  It could have been implemented without JIT changes as a wrapper on top of
  BPF_PROG_RUN() macro, but with two downsides:
  . all programs would have to pay performance penalty for this feature and
    tail call itself would be slower, since mandatory stack unwind, return,
    stack allocate would be done for every tailcall.
  . tailcall would be limited to programs running preempt_disabled, since
    generic 'void *ctx' doesn't have room for 'tail_call_cnt' and it would
    need to be either global per_cpu variable accessed by helper and by wrapper
    or global variable protected by locks.

  In this implementation x64 JIT bypasses stack unwind and jumps into the
  callee program after prologue.

- bpf_prog_array_compatible() ensures that prog_type of callee and caller
  are the same and JITed/non-JITed flag is the same, since calling JITed
  program from non-JITed is invalid, since stack frames are different.
  Similarly calling kprobe type program from socket type program is invalid.

- jump table is implemented as BPF_MAP_TYPE_PROG_ARRAY to reuse 'map'
  abstraction, its user space API and all of verifier logic.
  It's in the existing arraymap.c file, since several functions are
  shared with regular array map.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 17:07:59 -04:00
Daniel Borkmann
e7582bab5d net: dev: reduce both ingress hook ifdefs
Reduce ifdef pollution slightly, no functional change. We can simply
remove the extra alternative definition of handle_ing() and nf_ingress().

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 16:58:53 -04:00
Eric Dumazet
eb9344781a tcp: add a force_schedule argument to sk_stream_alloc_skb()
In commit 8e4d980ac2 ("tcp: fix behavior for epoll edge trigger")
we fixed a possible hang of TCP sockets under memory pressure,
by allowing sk_stream_alloc_skb() to use sk_forced_mem_schedule()
if no packet is in socket write queue.

It turns out there are other cases where we want to force memory
schedule :

tcp_fragment() & tso_fragment() need to split a big TSO packet into
two smaller ones. If we block here because of TCP memory pressure,
we can effectively block TCP socket from sending new data.
If no further ACK is coming, this hang would be definitive, and socket
has no chance to effectively reduce its memory usage.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 16:56:40 -04:00
Erik Kline
765c9c639f neigh: Better handling of transition to NUD_PROBE state
[1] When entering NUD_PROBE state via neigh_update(), perhaps received
    from userspace, correctly (re)initialize the probes count to zero.

    This is useful for forcing revalidation of a neighbor (for example
    if the host is attempting to do DNA [IPv4 4436, IPv6 6059]).

[2] Notify listeners when a neighbor goes into NUD_PROBE state.

    By sending notifications on entry to NUD_PROBE state listeners get
    more timely warnings of imminent connectivity issues.

    The current notifications on entry to NUD_STALE have somewhat
    limited usefulness: NUD_STALE is a perfectly normal state, as is
    NUD_DELAY, whereas notifications on entry to NUD_FAILURE come after
    a neighbor reachability problem has been confirmed (typically after
    three probes).

Signed-off-by: Erik Kline <ek@google.com>
Acked-By: Lorenzo Colitti <lorenzo@google.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21 16:52:17 -04:00
Alex Deucher
6ca121351b drm/radeon: fix error flag checking in native aux path
That atom table does not check these bits.  Fixes aux
regressions on some boards.

Reported-by: Malte Schröder <malte@tnxip.de>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2015-05-21 12:43:21 -04:00
Alex Deucher
0f28d1281b drm/radeon: retry dcpd fetch
Retry the dpcd fetch several times.  Some eDP panels
fail several times before the fetch is successful.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=73530

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2015-05-21 12:43:21 -04:00
Stephane Viau
755c814a7d drm/msm/mdp5: fix incorrect parameter for msm_framebuffer_iova()
The index of ->planes[] array (3rd parameter) cannot be equal to MAX_PLANE.
This looks like a typo that is now fixed.

Signed-off-by: Stephane Viau <sviau@codeaurora.org>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-05-21 14:31:45 +10:00