Set ethtool_ops->supported_coalesce_params to let
the core reject unsupported coalescing parameters.
This driver did not previously reject unsupported parameters.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The intention of this helper was to allow driver to specify one type
that it supports, so not only "any" value would pass. So make the API
more strict and allow driver to pass only 1 bit that is going
to be checked.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change the check to see if the passed allowed type bit is enabled.
Fixes: 319a1d1947 ("flow_offload: check for basic action hw stats type")
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of manually iterating over entries, use flow_action_for_each
helper. Move the helper and wrap it to fit to 80 cols on the way.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds all the necessary logic so that stmmac can be used with Synopsys
DesignWare XPCS.
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Synopsys DesignWare XPCS is an MMD that can manage link status,
auto-negotiation, link training, ...
In this commit we add basic support for XPCS using USXGMII interface and
Clause 73 Auto-negotiation.
This is highly tied with PHYLINK and can't be used without it. A given
ethernet driver can use the provided callbacks to add the support for
XPCS.
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Saeed Mahameed says:
====================
mlx5-updates-2020-03-09
This series provides updates to mlx5 driver:
1) Use vport metadata matching only when mandatory
2) Introduce root flow table and ethtool steering for uplink representors
3) Expose port speed via FW when link modes are not available
3) Misc cleanups
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Add TCP_NLA_BYTES_NOTSENT to SCM_TIMESTAMPING_OPT_STATS that reports
bytes in the write queue but not sent. This is the same metric as
what is exported with tcp_info.tcpi_notsent_bytes.
Signed-off-by: Yousuk Seung <ysseung@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This series adds some HW bits and definitions for mlx5 driver, to be
used by downstream features in both rdma and netdev branches.
* 'mlx5-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux:
net/mlx5: HW bit for goto chain offload support
net/mlx5: Expose link speed directly
net/mlx5: Introduce TLS and IPSec objects enums
net/mlx5: Introduce egress acl forward-to-vport capability
net/mlx5: Expose raw packet pacing APIs
net/mlx5e: Replace zero-length array with flexible-array member
net/mlx5: fix spelling mistake "reserverd" -> "reserved"
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Set up a subdev in the q6v5 modem remoteproc driver that generates
event notifications for the IPA driver to use for initialization and
recovery following a modem shutdown or crash.
A pair of new functions provides a way for the IPA driver to register
and deregister a notification callback function that will be called
whenever modem events (about to boot, running, about to shut down,
etc.) occur. A void pointer value (provided by the IPA driver at
registration time) and an event type are supplied to the callback
function.
One event, MODEM_REMOVING, is signaled whenever the q6v5 driver is
about to remove the notification subdevice. It requires the IPA
driver de-register its callback.
This sub-device is only used by the modem subsystem (MSS) driver,
so the code that adds the new subdev and allows registration and
deregistration of the notifier is found in "qcom_q6v6_mss.c".
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, user who is adding an action expects HW to report stats,
however it does not have exact expectations about the stats types.
That is aligned with TCA_ACT_HW_STATS_TYPE_ANY.
Allow user to specify the type of HW stats for an action and require it.
Pass the information down to flow_offload layer.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce new type for disabled HW stats and allow the value in
mlxsw offload.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce new type for delayed HW stats and allow the value in
mlx5 offload.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce new type for immediate HW stats and allow the value in
mlxsw offload.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce flow_action_basic_hw_stats_types_check() helper and use it
in drivers. That sanitizes the drivers which do not have support
for action HW stats types.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initially, pass "ANY" (struct is zeroed) to the drivers as that is the
current implicit value coming down to flow_offload. Add a bool
indicating that entries have mixed HW stats type.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Expose port rate as part of the port speed register fields.
Signed-off-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Expose the TLS encryption key general object type enum correctly,
and add the IPSec encryption key general object type enum.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Add HCA_CAP.egress_acl_forward_to_vport field to check whether HW
supports e-switch vport's egress acl to forward packets to other
e-switch vport or not.
By default E-Switch egress ACL forwards eswitch vports egress packets
to their corresponding NIC/VF vports.
With this cap enabled, the driver is allowed to alter this behavior
and forward packets to arbitrary NIC/VF vports with the following
limitations:
a. Multiple processing paths are supported if all of the following
conditions are met:
- HCA_CAP.egress_acl_forward_to_vport is set ==1.
- A destination of type Flow Table only appears once, as the
last destination in the list.
- Vport destination is supported if
HCA_CAP.egress_acl_forward_to_vport==1. Vport must not be
the Uplink.
b. Flow_tag not supported.
c. This table is only applicable after an FDB table is created.
d. Push VLAN action is not supported.
e. Pop VLAN action cannot be added concurrently to this table and
FDB table.
This feature will be used during port failover in bonding scenario
where two VFs representors are bonded to handle failover egress traffic
(VM's ingress/receive traffic).
Signed-off-by: Vu Pham <vuhuong@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Several device drivers read their Device Serial Number from the PCIe
extended config space.
Introduce a new helper function, pci_get_dsn(). This function reads the
eight bytes of the DSN and returns them as a u64. If the capability does not
exist for the device, the function returns 0.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Michael Chan <michael.chan@broadcom.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Invoke ndo_setup_tc() as appropriate to signal init / replacement,
destroying and dumping of pFIFO / bFIFO Qdisc.
A lot of the FIFO logic is used for pFIFO_head_drop as well, but that's a
semantically very different Qdisc that isn't really in the same boat as
pFIFO / bFIFO. Split some of the functions to keep the Qdisc intact.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux supports 22 different interrupt coalescing parameters.
No driver implements them all. Some drivers just ignore the
ones they don't support, while others have to carry a long
list of checks to reject unsupported settings.
To simplify the drivers add the ability to specify inside
ethtool_ops which parameters are supported and let the core
reject attempts to set any other one.
This commit makes the mechanism an opt-in, only drivers which
set ethtool_opts->coalesce_types to a non-zero value will have
the checks enforced.
The same mask is used for global and per queue settings.
v3: - move the (temporary) check if driver defines types
earlier (Michal)
- rename used_types -> nonzero_params, and
coalesce_types -> supported_coalesce_params (Alex)
- use EOPNOTSUPP instead of EINVAL (Andrew, Michal)
Leaving the long series of ifs for now, it seems nice to
be able to grep for the field and flag names. This will
probably have to be revisited once netlink support lands.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Expose raw packet pacing APIs to be used by DEVX based applications.
The existing code was refactored to have a single flow with the new raw
APIs.
The new raw APIs considered the input of 'pp_rate_limit_context', uid,
'dedicated', upon looking for an existing entry.
This raw mode enables future device specification data in the raw
context without changing the existing logic and code.
The ability to ask for a dedicated entry gives control for application
to allocate entries according to its needs.
A dedicated entry may not be used by some other process and it also
enables the process spreading its resources to some different entries
for use different hardware resources as part of enforcing the rate.
The counter per entry was changed to be u64 to prevent any option to
overflow.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Acked-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Several drivers use the following code sequence:
1. Read PCI_STATUS
2. Mask out non-error bits
3. Action based on error bits set
4. Write back set error bits to clear them
As this is a repeated pattern, add a helper to the PCI core.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This collection of PCI error bits is used in more than one driver,
so move it to the PCI core.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Compared to other DSA switches, in the Ocelot cores, the RX filtering is
a much more important concern.
Firstly, the primary use case for Ocelot is non-DSA, so there isn't any
secondary Ethernet MAC [the DSA master's one] to implicitly drop frames
having a DMAC we are not interested in. So the switch driver itself
needs to install FDB entries towards the CPU port module (PGID_CPU) for
the MAC address of each switch port, in each VLAN installed on the port.
Every address that is not whitelisted is implicitly dropped. This is in
order to achieve a behavior similar to N standalone net devices.
Secondly, even in the secondary use case of DSA, such as illustrated by
Felix with the NPI port mode, that secondary Ethernet MAC is present,
but its RX filter is bypassed. This is because the DSA tags themselves
are placed before Ethernet, so the DMAC that the switch ports see is
not seen by the DSA master too (since it's shifter to the right).
So RX filtering is pretty important. A good RX filter won't bother the
CPU in case the switch port receives a frame that it's not interested
in, and there exists no other line of defense.
Ocelot is pretty strict when it comes to RX filtering: non-IP multicast
and broadcast traffic is allowed to go to the CPU port module, but
unknown unicast isn't. This means that traffic reception for any other
MAC addresses than the ones configured on each switch port net device
won't work. This includes use cases such as macvlan or bridging with a
non-Ocelot (so-called "foreign") interface. But this seems to be fine
for the scenarios that the Linux system embedded inside an Ocelot switch
is intended for - it is simply not interested in unknown unicast
traffic, as explained in Allan Nielsen's presentation [0].
On the other hand, the Felix DSA switch is integrated in more
general-purpose Linux systems, so it can't afford to drop that sort of
traffic in hardware, even if it will end up doing so later, in software.
Actually, unknown unicast means more for Felix than it does for Ocelot.
Felix doesn't attempt to perform the whitelisting of switch port MAC
addresses towards PGID_CPU at all, mainly because it is too complicated
to be feasible: while the MAC addresses are unique in Ocelot, by default
in DSA all ports are equal and inherited from the DSA master. This adds
into account the question of reference counting MAC addresses (delayed
ocelot_mact_forget), not to mention reference counting for the VLAN IDs
that those MAC addresses are installed in. This reference counting
should be done in the DSA core, and the fact that it wasn't needed so
far is due to the fact that the other DSA switches don't have the DSA
tag placed before Ethernet, so the DSA master is able to whitelist the
MAC addresses in hardware.
So this means that even regular traffic termination on a Felix switch
port happens through flooding (because neither Felix nor Ocelot learn
source MAC addresses from CPU-injected frames).
So far we've explained that whitelisting towards PGID_CPU:
- helps to reduce the likelihood of spamming the CPU with frames it
won't process very far anyway
- is implemented in the ocelot driver
- is sufficient for the ocelot use cases
- is not feasible in DSA
- breaks use cases in DSA, in the current status (whitelisting enabled
but no MAC address whitelisted)
So the proposed patch allows unknown unicast frames to be sent to the
CPU port module. This is done for the Felix DSA driver only, as Ocelot
seems to be happy without it.
[0]: https://www.youtube.com/watch?v=B1HhxEcU7Jg
Suggested-by: Allan W. Nielsen <allan.nielsen@microchip.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Allan W. Nielsen <allan.nielsen@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ocelot has the concept of a CPU port. The CPU port is represented in the
forwarding and the queueing system, but it is not a physical device. The
CPU port can either be accessed via register-based injection/extraction
(which is the case of Ocelot), via Frame-DMA (similar to the first one),
or "connected" to a physical Ethernet port (called NPI in the datasheet)
which is the case of the Felix DSA switch.
In Ocelot the CPU port is at index 11.
In Felix the CPU port is at index 6.
The CPU bit is treated special in the forwarding, as it is never cleared
from the forwarding port mask (once added to it). Other than that, it is
treated the same as a normal front port.
Both Felix and Ocelot should use the CPU port in the same way. This
means that Felix should not use the NPI port directly when forwarding to
the CPU, but instead use the CPU port.
This patch is fixing this such that Felix will use port 6 as its CPU
port, and just use the NPI port to carry the traffic.
Therefore, eliminate the "ocelot->cpu" variable which was holding the
index of the NPI port for Felix, and the index of the CPU port module
for Ocelot, so the variable was actually configuring different things
for different drivers and causing at least part of the confusion.
Also remove the "ocelot->num_cpu_ports" variable, which is the result of
another confusion. The 2 CPU ports mentioned in the datasheet are
because there are two frame extraction channels (register based or DMA
based). This is of no relevance to the driver at the moment, and
invisible to the analyzer module.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Suggested-by: Allan W. Nielsen <allan.nielsen@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Realign a comment after the change introduced by the
previous patch.
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The variable pie_vars->accu_prob is used as an accumulator for
probability values. Since probabilty values are scaled using the
MAX_PROB macro denoting (2^64 - 1), pie_vars->accu_prob is
likely to overflow as it is of type u64.
The variable pie_vars->accu_prob_overflows counts the number of
times the variable pie_vars->accu_prob overflows.
The MAX_PROB macro needs to be equal to at least (2^39 - 1) in
order to do precise calculations without any underflow. Thus
MAX_PROB can be reduced to (2^56 - 1) without affecting the
precision in calculations drastically. Doing so will eliminate
the need for the variable pie_vars->accu_prob_overflows as the
variable pie_vars->accu_prob will never overflow.
Removing the variable pie_vars->accu_prob_overflows also reduces
the size of the structure pie_vars to exactly 64 bytes.
Signed-off-by: Mohit P. Tahiliani <tahiliani@nitk.edu.in>
Signed-off-by: Gautam Ramakrishnan <gautamramk@gmail.com>
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove ambiguity by using the term backlog instead of qlen when
representing the queue length in bytes.
Signed-off-by: Mohit P. Tahiliani <tahiliani@nitk.edu.in>
Signed-off-by: Gautam Ramakrishnan <gautamramk@gmail.com>
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Export the cls_flower methods from the ocelot driver and hook them up to
the DSA passthrough layer.
Tables for the VCAP IS2 parameters, as well as half key packing (field
offsets and lengths) need to be defined for the VSC9959 core, as they
are different from Ocelot, mainly due to the different port count.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Due to the immense variety of classification keys and actions available
for tc-flower, as well as due to potentially very different DSA switch
capabilities, it doesn't make a lot of sense for the DSA mid layer to
even attempt to interpret these. So just pass them on to the underlying
switch driver.
DSA implements just the standard boilerplate for binding and unbinding
flow blocks to ports, since nobody wants to deal with that.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the definitions for the VCAP IS2 table from ocelot_ace.c, since
it is specific to VSC7514.
The VSC9959 VCAP IS2 table supports more rules (1024 instead of 64) and
has a different width for the action (89 bits instead of 99).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Felix driver is now using its own PHYLINK instance, not calling into
ocelot_adjust_link. So the port_pcs_init function pointer is an
unnecessary indirection. Remove it.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Allan W. Nielsen <allan.nielsen@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The IGR_PORT_MASK key width is different between the 11-port VSC7514 and
the 6-port VSC9959 switches. And since IGR_PORT_MASK is one of the first
fields of a VCAP key entry, it means that all further field
offset/length pairs are shifted between the 2.
The ocelot driver performs packing of VCAP half keys with the help of
some preprocessor macros:
- A set of macros for defining the HKO (Half Key Offset) and HKL (Half
Key Length) of each possible key field. The offset of each field is
defined as the sum between the offset and the sum of the previous
field.
- A set of accessors on top of vcap_key_set for shorter (aka less
typing) access to the HKO and HKL of each key field.
Since the field offsets and lengths are different between switches,
defining them through the preprocessor isn't going to fly. So introduce
a structure holding (offset, length) pairs and instantiate it in
ocelot_board.c for VSC7514. In a future patch, a similar structure will
be instantiated in felix_vsc9959.c for NXP LS1028A.
The accessors also need to go. They are based on macro name
concatenation, which is horrible to understand and follow.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ocelot tc-flower offload binds a second flow block callback (apart
from the one for matchall) just because it uses a different block
private structure (ocelot_port_private for matchall, ocelot_port_block
for flower).
But ocelot_port_block just appears to be boilerplate, and doesn't help
with anything in particular at all, it's just useless glue between the
(global!) struct ocelot_acl_block *block pointer, and a per-netdevice
struct ocelot_port_private *priv.
So let's just simplify that, and make struct ocelot_port_private be the
private structure for the block offload. This makes us able to use the
same flow callback as in the case of matchall.
This also reveals that the struct ocelot_acl_block *block is used rather
strangely, as mentioned above: it is defined globally, allocated at
probe time, and freed at unbind time. So just move the structure to the
main ocelot structure, which gives further opportunity for
simplification.
Also get rid of backpointers from struct ocelot_acl_block and struct
ocelot_ace_rule back to struct ocelot, by reworking the function
prototypes, where necessary, to use a more DSA-friendly "struct ocelot
*ocelot, int port" format.
And finally, remove the debugging prints that were added during
development, since they provide no useful information at this point.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Allan W. Nielsen <allan.nielsen@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently mlx5 PCI PF and VF devlink devices register their ports as
physical port in non-representors mode.
Introduce a new port flavour as virtual so that virtual devices can
register 'virtual' flavour to make it more clear to users.
An example of one PCI PF and 2 PCI virtual functions, each having
one devlink port.
$ devlink port show
pci/0000:06:00.0/1: type eth netdev ens2f0 flavour physical port 0
pci/0000:06:00.2/1: type eth netdev ens2f2 flavour virtual port 0
pci/0000:06:00.3/1: type eth netdev ens2f3 flavour virtual port 0
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the NF flow tables infrastructure for CT offload.
Create a nf flow table per zone.
Next patches will add FT entries to this table, and do
the software offload.
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
