RFC1662 defines the start state for the crc16 FCS to be 0xffff, but
we're currently starting at zero.
This change uses the correct start state. We're only early in the
adoption for the serial binding, so there aren't yet any other users to
interface to.
Fixes: a0c2ccd9b5 ("mctp: Add MCTP-over-serial transport binding")
Reported-by: Harsh Tyagi <harshtya@google.com>
Tested-by: Harsh Tyagi <harshtya@google.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We're currently hitting the WARN_ON in mctp_i2c_flow_release:
if (midev->release_count > midev->i2c_lock_count) {
WARN_ONCE(1, "release count overflow");
This may be hit if we expire a flow before sending the first packet it
contains - as we will not be pairing the increment of release_count
(performed on flow release) with the i2c lock operation (only
performed on actual TX).
To fix this, only release a flow if we've encountered it previously (ie,
dev_flow_state does not indicate NEW), as we will mark the flow as
ACTIVE at the same time as accounting for the i2c lock operation. We
also need to add an INVALID flow state, to indicate when we've done the
release.
Fixes: f5b8abf9fc ("mctp i2c: MCTP I2C binding driver")
Reported-by: Jian Zhang <zhangjian.3032@bytedance.com>
Tested-by: Jian Zhang <zhangjian.3032@bytedance.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20221110053135.329071-1-jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The value returned by an i2c driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)
So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.
Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Crt Mori <cmo@melexis.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/*
Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5
Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio
Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860
Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b
Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes
Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power
Acked-by: Krzysztof Hałasa <khalasa@piap.pl>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
header_ops.create should return the length of the header,
instead mctp_i2c_head_create() returned 0.
This didn't cause any problem because the MCTP stack accepted
0 as success.
Fixes: f5b8abf9fc ("mctp i2c: MCTP I2C binding driver")
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit
baebdf48c3 ("net: dev: Makes sure netif_rx() can be invoked in any context.")
the function netif_rx() can be used in preemptible/thread context as
well as in interrupt context.
Use netif_rx().
Cc: Jeremy Kerr <jk@codeconstruct.com.au>
Cc: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
We should be testing the length before fitting into the u8 byte_count.
This is just a sanity check, the MCTP stack should have limited to MTU
which is checked, and we check consistency later in mctp_i2c_xmit().
Found by Smatch
mctp_i2c_header_create() warn: impossible condition
'(hdr->byte_count > 255) => (0-255 > 255)'
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The skb is handed off to netif_rx() which may free it.
Found by Smatch.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Provides MCTP network transport over an I2C bus, as specified in
DMTF DSP0237. All messages between nodes are sent as SMBus Block Writes.
Each I2C bus to be used for MCTP is flagged in devicetree by a
'mctp-controller' property on the bus node. Each flagged bus gets a
mctpi2cX net device created based on the bus number. A
'mctp-i2c-controller' I2C client needs to be added under the adapter. In
an I2C mux situation the mctp-i2c-controller node must be attached only
to the root I2C bus. The I2C client will handle incoming I2C slave block
write data for subordinate busses as well as its own bus.
In configurations without devicetree a driver instance can be attached
to a bus using the I2C slave new_device mechanism.
The MCTP core will hold/release the MCTP I2C device while responses
are pending (a 6 second timeout or once a socket is closed, response
received etc). While held the MCTP I2C driver will lock the I2C bus so
that the correct I2C mux remains selected while responses are received.
(Ideally we would just lock the mux to keep the current bus selected for
the response rather than a full I2C bus lock, but that isn't exposed in
the I2C mux API)
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Wolfram Sang <wsa@kernel.org> # I2C transport parts
Signed-off-by: David S. Miller <davem@davemloft.net>
We cannot do the cancel_work_sync from after the unregister_netdev, as
the dev pointer is no longer valid, causing a uaf on ldisc unregister
(or device close).
Instead, do the cancel_work_sync from the ndo_uninit op, where the dev
still exists, but the queue has stopped.
Fixes: 7bd9890f3d ("mctp: serial: cancel tx work on ldisc close")
Reported-by: Luo Likang <luolikang@nsfocus.com>
Tested-by: Luo Likang <luolikang@nsfocus.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20220211011552.1861886-1-jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jiri assures me that a ldisc->open with tty->disc_data set should never
happen, so this check doesn't do anything.
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The current serial driver requires a maximum MTU of 68, and it doesn't
make sense to set a MTU below the MCTP-required baseline (of 68) either.
This change sets the min_mtu & max_mtu of the mctp netdev, essentially
disallowing changes. By using these instead of a ndo_change_mtu op, we
get the netlink extacks reported too.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We want to ensure that the tx work has finished before returning from
the ldisc close op, so do a synchronous cancel.
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This change adds a MCTP Serial transport binding, as defined by DMTF
specificiation DSP0253 - "MCTP Serial Transport Binding". This is
implemented as a new serial line discipline, and can be attached to
arbitrary tty devices.
From the Kconfig description:
This driver provides an MCTP-over-serial interface, through a
serial line-discipline, as defined by DMTF specification "DSP0253 -
MCTP Serial Transport Binding". By attaching the ldisc to a serial
device, we get a new net device to transport MCTP packets.
This allows communication with external MCTP endpoints which use
serial as their transport. It can also be used as an easy way to
provide MCTP connectivity between virtual machines, by forwarding
data between simple virtual serial devices.
Say y here if you need to connect to MCTP endpoints over serial. To
compile as a module, use m; the module will be called mctp-serial.
Once the N_MCTP line discipline is set [using ioctl(TCIOSETD)], we get a
new netdev suitable for MCTP communication.
The 'mctp' utility[1] provides a simple wrapper for this ioctl, using
'link serial <device>':
# mctp link serial /dev/ttyS0 &
# mctp link
dev lo index 1 address 0x00:00:00:00:00:00 net 1 mtu 65536 up
dev mctpserial0 index 5 address 0x(no-addr) net 1 mtu 68 down
[1]: https://github.com/CodeConstruct/mctp
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 71812af723, reversing
changes made to cc0be1ad68.
Wolfram Sang says:
Please revert. Besides the driver in net, it modifies the I2C core
code. This has not been acked by the I2C maintainer (in this case me).
So, please don't pull this in via the net tree. The question raised here
(extending SMBus calls to 255 byte) is complicated because we need ABI
backwards compatibility.
Link: https://lore.kernel.org/all/YZJ9H4eM%2FM7OXVN0@shikoro/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Provides MCTP network transport over an I2C bus, as specified in
DMTF DSP0237. All messages between nodes are sent as SMBus Block Writes.
Each I2C bus to be used for MCTP is flagged in devicetree by a
'mctp-controller' property on the bus node. Each flagged bus gets a
mctpi2cX net device created based on the bus number. A
'mctp-i2c-controller' I2C client needs to be added under the adapter. In
an I2C mux situation the mctp-i2c-controller node must be attached only
to the root I2C bus. The I2C client will handle incoming I2C slave block
write data for subordinate busses as well as its own bus.
In configurations without devicetree a driver instance can be attached
to a bus using the I2C slave new_device mechanism.
The MCTP core will hold/release the MCTP I2C device while responses
are pending (a 6 second timeout or once a socket is closed, response
received etc). While held the MCTP I2C driver will lock the I2C bus so
that the correct I2C mux remains selected while responses are received.
(Ideally we would just lock the mux to keep the current bus selected for
the response rather than a full I2C bus lock, but that isn't exposed in
the I2C mux API)
This driver requires I2C adapters that allow 255 byte transfers
(SMBus 3.0) as the specification requires a minimum MTU of 68 bytes.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add an empty drivers/net/mctp/, for future interface drivers.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jeremy Kerr