There is no guarantee that the skb is in the same state after calling
net_receive_skb() or netif_rx(). It might be freed or reused. Not really
harmful as its a read access, except you turn on the proper debugging options
which catch a use after free.
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Commit 514ac99c64 "can: fix multiple delivery of a single CAN frame for
overlapping CAN filters" requires the skb->tstamp to be set to check for
identical CAN skbs.
Without timestamping to be required by user space applications this timestamp
was not generated which lead to commit 36c01245eb "can: fix loss of CAN frames
in raw_rcv" - which forces the timestamp to be set in all CAN related skbuffs
by introducing several __net_timestamp() calls.
This forces e.g. out of tree drivers which are not using alloc_can{,fd}_skb()
to add __net_timestamp() after skbuff creation to prevent the frame loss fixed
in mainline Linux.
This patch removes the timestamp dependency and uses an atomic counter to
create an unique identifier together with the skbuff pointer.
Btw: the new skbcnt element introduced in struct can_skb_priv has to be
initialized with zero in out-of-tree drivers which are not using
alloc_can{,fd}_skb() too.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
As reported by Manfred Schlaegl here
http://marc.info/?l=linux-netdev&m=143482089824232&w=2
commit 514ac99c64 "can: fix multiple delivery of a single CAN frame for
overlapping CAN filters" requires the skb->tstamp to be set to check for
identical CAN skbs.
As net timestamping is influenced by several players (netstamp_needed and
netdev_tstamp_prequeue) Manfred missed a proper timestamp which leads to
CAN frame loss.
As skb timestamping became now mandatory for CAN related skbs this patch
makes sure that received CAN skbs always have a proper timestamp set.
Maybe there's a better solution in the future but this patch fixes the
CAN frame loss so far.
Reported-by: Manfred Schlaegl <manfred.schlaegl@gmx.at>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Several can modules in drivers/net/can use a banner[] variable at the
top which defines a string that is used once during init. This string
is also embedded with KERN_INFO which makes it printk() specific.
Improve the code by eliminating the banner[] variable and moving the
string to where it is printed. Then switch from printk(KERN_INFO to
pr_info() for the lines that were changed.
This patch is similar to [1] which was applied to net/can.
[1]: https://lkml.org/lkml/2014/11/22/10
Signed-off-by: Jeremiah Mahler <jmmahler@gmail.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The commit "slip: Fix deadlock in write_wakeup" fixes a deadlock caused
by a change made in both slcan and slip. This is a direct port of that
fix.
Signed-off-by: Tyler Hall <tylerwhall@gmail.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Andre Naujoks <nautsch2@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
slc_xmit is called within softirq context and locks sl->lock, but
slcan_write_wakeup is not softirq context, so we need to use
spin_[un]lock_bh!
Detected using kernel lock debugging mechanism.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
CAN interfaces only support MTU values of 16 (CAN 2.0) and 72 (CAN FD).
Setting the MTU to other values is pointless but it does not really hurt.
With the introduction of the CAN FD support in drivers/net/can a new
function to switch the MTU for CAN FD has been introduced.
This patch makes use of this can_change_mtu() function to check for correct
MTU settings also in legacy CAN (2.0) devices.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Several files refer to an old address for the Free Software Foundation
in the file header comment. Resolve by replacing the address with
the URL <http://www.gnu.org/licenses/> so that we do not have to keep
updating the header comments anytime the address changes.
CC: Wolfgang Grandegger <wg@grandegger.com>
CC: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The old implementation was heavy on str* functions and sprintf calls.
This version is more manual, but faster.
Profiling just the printing of a 3 char CAN-id resulted in 60 instructions
for the manual method and over 2000 for the sprintf method. Bear in
mind the profiling was done against libc and not the kernel sprintf.
Together with this rewrite an issue with sending and receiving of RTR frames
has been fixed by Oliver for the cases that the DLC is not zero.
Signed-off-by: Andre Naujoks <nautsch2@gmail.com>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The locking is needed, since the the internal buffer for the CAN frames is
changed during the wakeup call. This could cause buffer inconsistencies
under high loads, especially for the outgoing short CAN packet skbuffs.
The needed locks led to deadlocks before commit
"5ede52538ee2b2202d9dff5b06c33bfde421e6e4 tty: Remove extra wakeup from pty
write() path", which removed the direct callback to the wakeup function from the
tty layer.
As slcan.c is based on slip.c the issue in the original code is fixed, too.
Signed-off-by: Andre Naujoks <nautsch2@gmail.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The usage of strict_strtoul() is not preferred, because
strict_strtoul() is obsolete. Thus, kstrtoul() should be
used.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Added accessor and skb_reserve helpers for struct can_skb_priv.
Removed pointless skb_headroom() check.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
CC: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The struct can_skb_priv is used to transport additional information along
with the stored struct can(fd)_frame that can not be contained in existing
struct sk_buff elements.
can_skb_priv is located in the skb headroom, which does not touch the existing
CAN sk_buff usage with skb->data and skb->len, so that even out-of-tree
CAN drivers can be used without changes.
Btw. out-of-tree CAN drivers without can_skb_priv in the sk_buff headroom
would not support features based on can_skb_priv.
The can_skb_priv->ifindex contains the first interface where the CAN frame
appeared on the local host. Unfortunately skb->skb_iif can not be used as this
value is overwritten in every netif_receive_skb() call.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Remove all #inclusions of asm/system.h preparatory to splitting and killing
it. Performed with the following command:
perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: David Howells <dhowells@redhat.com>
alloc failures use dump_stack so emitting an additional
out-of-memory message is an unnecessary duplication.
Remove the allocation failure messages.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The reorganization of the driver layout in drivers/net
left behind some stale paths in comments and in Kconfig
help text. Bring them up to date. No actual change to
any code takes place here.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Only distinct use is checking if NETIF_F_NOCACHE_COPY should be
enabled by default. The check heuristics is altered a bit here,
so it hits other people than before. The default shouldn't be
trusted for performance-critical cases anyway.
For all other uses NETIF_F_NO_CSUM is equivalent to NETIF_F_HW_CSUM.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
The BerliOS project, which currently hosts our mailinglist, will
close with the end of the year. Now take the chance and remove all
occurrences of the mailinglist address from the source files.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
As this discussion pointed out
http://marc.info/?l=linux-netdev&m=131257225602375
netdevices that are based on serial line disciplines should use netif_rx_ni()
when pushing received socketbuffers into the netdev rx queue.
Following commit 614851601c ("slip: fix NOHZ
local_softirq_pending 08 warning") this patch updates the slcan driver
accordingly.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
CC: Matvejchikov Ilya <matvejchikov@gmail.com>
CC: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes obsolete code in the initialisation/creation of
slcan devices.
It follows the suggested cleanups from Ilya Matvejchikov in
drivers/net/slip.c that where recently applied to net-next-2.6:
- slip: remove dead code within the slip initialization
- slip: remove redundant check slip_devs for NULL
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit b1c43f82c5.
It was broken in so many ways, and results in random odd pty issues.
It re-introduced the buggy schedule_work() in flush_to_ldisc() that can
cause endless work-loops (see commit a5660b41af: "tty: fix endless
work loop when the buffer fills up").
It also used an "unsigned int" return value fo the ->receive_buf()
function, but then made multiple functions return a negative error code,
and didn't actually check for the error in the caller.
And it didn't actually work at all. BenH bisected down odd tty behavior
to it:
"It looks like the patch is causing some major malfunctions of the X
server for me, possibly related to PTYs. For example, cat'ing a
large file in a gnome terminal hangs the kernel for -minutes- in a
loop of what looks like flush_to_ldisc/workqueue code, (some ftrace
data in the quoted bits further down).
...
Some more data: It -looks- like what happens is that the
flush_to_ldisc work queue entry constantly re-queues itself (because
the PTY is full ?) and the workqueue thread will basically loop
forver calling it without ever scheduling, thus starving the consumer
process that could have emptied the PTY."
which is pretty much exactly the problem we fixed in a5660b41af.
Milton Miller pointed out the 'unsigned int' issue.
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reported-by: Milton Miller <miltonm@bga.com>
Cc: Stefan Bigler <stefan.bigler@keymile.com>
Cc: Toby Gray <toby.gray@realvnc.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (48 commits)
serial: 8250_pci: add support for Cronyx Omega PCI multiserial board.
tty/serial: Fix break handling for PORT_TEGRA
tty/serial: Add explicit PORT_TEGRA type
n_tracerouter and n_tracesink ldisc additions.
Intel PTI implementaiton of MIPI 1149.7.
Kernel documentation for the PTI feature.
export kernel call get_task_comm().
tty: Remove to support serial for S5P6442
pch_phub: Support new device ML7223
8250_pci: Add support for the Digi/IBM PCIe 2-port Adapter
ASoC: Update cx20442 for TTY API change
pch_uart: Support new device ML7223 IOH
parport: Use request_muxed_region for IT87 probe and lock
tty/serial: add support for Xilinx PS UART
n_gsm: Use print_hex_dump_bytes
drivers/tty/moxa.c: Put correct tty value
TTY: tty_io, annotate locking functions
TTY: serial_core, remove superfluous set_task_state
TTY: serial_core, remove invalid test
Char: moxa, fix locking in moxa_write
...
Fix up trivial conflicts in drivers/bluetooth/hci_ldisc.c and
drivers/tty/serial/Makefile.
I did the hci_ldisc thing as an evil merge, cleaning things up.
TTY layer expects 0 if the ldisc->open operation succeeded.
Reported-by: Matvejchikov Ilya <matvejchikov@gmail.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.
Tested-by: Stefan Bigler <stefan.bigler@keymile.com>
Tested-by: Toby Gray <toby.gray@realvnc.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/net/can/slcan.c: In function 'slcan_open':
drivers/net/can/slcan.c:568: error: dereferencing pointer to incomplete type
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for serial/USB-serial CAN adapters implementing the
LAWICEL ASCII protocol for CAN frame transport over serial lines.
The driver implements the SLCAN line discipline and is heavily based on the
slip.c driver. Therefore the code style remains similar to slip.c to be able
to apply changes of the SLIP driver to the SLCAN driver easily.
For more details see the slcan Kconfig entry.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
