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While porting a RS485 driver from 2.6.29 to 3.14, i noticed that the serial tty
driver could break it by using uart ports that it does not own :
1. uart_change_pm ist called during uart_open and calls the uart pm function
without checking for PORT_UNKNOWN.
The fix is to move uart_change_pm from uart_open to uart_port_startup.
2. The return code from the uart request_port call in uart_set_info is not
handled properly, leading to the situation that the serial driver also
thinks it owns the uart ports.
This can triggered by doing following actions :
setserial /dev/ttyS0 uart none # release the uart ports
modprobe lirc-serial # or any other device that uses the uart
setserial /dev/ttyS0 uart 16550 # gives no error and the uart tty driver
# can use the ports as well
Signed-off-by: Thomas Pfaff <tpfaff@pcs.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The two functions to write out to the console (one used in normal
console mode and one in polling console mode) were slightly different.
One used a barrier() in its loop and the other a cpu_relax(). The
barrier() really doesn't do anything since we're using rd_regl() to
read the port anyway. Switch it to cpu_relax() to make things
consistent.
No known bugs / issues are fixed by this change--it just makes things
more consistent.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The s3c24xx_serial_console_putchar() is _only_ ever used by
s3c24xx_serial_console_write() and is called in a loop (indirectly
through uart_console_write()). There's no reason to call
s3c24xx_port_configured() for every iteration through the loop. Move
it outside the loop.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The two functions in the samsung serial driver used for writing
characters out to the port were inconsistent about whether they used
the passed in "port" or the global "cons_uart". There was no reason
to use the global and the use of the global in
s3c24xx_serial_put_poll_char() caused a crash in the case where you
used the serial port for kgdboc but not for console.
Fix it so we used the passed in variable.
Note that this doesn't fix all problems with the samsung serial
driver. Specifically:
* s3c24xx_serial_console_putchar() is still 99% identical to
s3c24xx_serial_put_poll_char() (the function signature is different,
but that's about it). A future patch will make them slightly less
identical and judging by other serial drivers we may need yet more
differences eventually.
* The samsung serial driver still doesn't allow you to have more than
one console port since it still uses the global cons_uart in
s3c24xx_serial_console_write().
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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__dma_tx_complete is not protected against concurrent
call of serial8250_tx_dma. it can lead to circular tail
index corruption or parallel call of serial_tx_dma on the
same data portion.
This patch fixes this issue by holding the port lock.
Signed-off-by: Loic Poulain <loic.poulain@intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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On transmit-hold-register empty, serial8250_tx_chars
should be called only if we don't use DMA.
DMA has its own tx cycle.
Signed-off-by: Loic Poulain <loic.poulain@intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The race was introduced while development of linux-3.11 by
e8437d7ecbc50198705331449367d401ebb3181f and
e9975fdec0138f1b2a85b9624e41660abd9865d4.
Originally it was found and reproduced on linux-3.12.15 and
linux-3.12.15-rt25, by sending 500 byte blocks with 115kbaud to the
target uart in a loop with 100 milliseconds delay.
In short:
1. The consumer flush_to_ldisc is on to remove the head tty_buffer.
2. The producer adds a number of bytes, so that a new tty_buffer must
be allocated and added by __tty_buffer_request_room.
3. The consumer removes the head tty_buffer element, without handling
newly committed data.
Detailed example:
* Initial buffer:
* Head, Tail -> 0: used=250; commit=250; read=240; next=NULL
* Consumer: ''flush_to_ldisc''
* consumed 10 Byte
* buffer:
* Head, Tail -> 0: used=250; commit=250; read=250; next=NULL
{{{
count = head->commit - head->read; // count = 0
if (!count) { // enter
// INTERRUPTED BY PRODUCER ->
if (head->next == NULL)
break;
buf->head = head->next;
tty_buffer_free(port, head);
continue;
}
}}}
* Producer: tty_insert_flip_... 10 bytes + tty_flip_buffer_push
* buffer:
* Head, Tail -> 0: used=250; commit=250; read=250; next=NULL
* added 6 bytes: head-element filled to maximum.
* buffer:
* Head, Tail -> 0: used=256; commit=250; read=250; next=NULL
* added 4 bytes: __tty_buffer_request_room is called
* buffer:
* Head -> 0: used=256; commit=256; read=250; next=1
* Tail -> 1: used=4; commit=0; read=250 next=NULL
* push (tty_flip_buffer_push)
* buffer:
* Head -> 0: used=256; commit=256; read=250; next=1
* Tail -> 1: used=4; commit=4; read=250 next=NULL
* Consumer
{{{
count = head->commit - head->read;
if (!count) {
// INTERRUPTED BY PRODUCER <-
if (head->next == NULL) // -> no break
break;
buf->head = head->next;
tty_buffer_free(port, head);
// ERROR: tty_buffer head freed -> 6 bytes lost
continue;
}
}}}
This patch reintroduces a spin_lock to protect this case. Perhaps later
a lock-less solution could be found.
Signed-off-by: Manfred Schlaegl <manfred.schlaegl@gmx.at>
Cc: stable <stable@vger.kernel.org> # 3.11
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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git://git.linaro.org/people/pawel.moll/linux into fixes
ARM Versatile Express fixes for 3.15
This series contains straight-forward fixes for different
Versatile Express infrastructure drivers:
- NULL pointer dereference on the error path in the clk driver
- out of boundary array access in the dcscb driver
- broken restart/power off implementation
- mis-interpreted voltage unit in the spc driver
* tag 'vexpress/fixes-for-3.15' of git://git.linaro.org/people/pawel.moll/linux:
ARM: vexpress/TC2: Convert OPP voltage to uV before storing
power/reset: vexpress: Fix restart/power off operation
arm/mach-vexpress: array accessed out of bounds
clk: vexpress: NULL dereference on error path
Includes an update to 3.15-rc2
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Currently we get the following kind of errors if we try to use interrupt
phandles to irqchips that have not yet initialized:
irq: no irq domain found for /ocp/pinmux@48002030 !
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/of/platform.c:171 of_device_alloc+0x144/0x184()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-00038-g42a9708 #1012
(show_stack+0x14/0x1c)
(dump_stack+0x6c/0xa0)
(warn_slowpath_common+0x64/0x84)
(warn_slowpath_null+0x1c/0x24)
(of_device_alloc+0x144/0x184)
(of_platform_device_create_pdata+0x44/0x9c)
(of_platform_bus_create+0xd0/0x170)
(of_platform_bus_create+0x12c/0x170)
(of_platform_populate+0x60/0x98)
This is because we're wrongly trying to populate resources that are not
yet available. It's perfectly valid to create irqchips dynamically, so
let's fix up the issue by resolving the interrupt resources when
platform_get_irq is called.
And then we also need to accept the fact that some irqdomains do not
exist that early on, and only get initialized later on. So we can
make the current WARN_ON into just into a pr_debug().
We still attempt to populate irq resources when we create the devices.
This allows current drivers which don't use platform_get_irq to continue
to function. Once all drivers are fixed, this code can be removed.
Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Grant Likely <grant.likely@linaro.org>
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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>
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When trying to set a data bitrate on non CAN FD devices the 'ip' tool
answers with:
RTNETLINK answers: Unknown error 524
Rename '-ENOTSUPP' to '-EOPNOTSUPP' so that 'ip' answers correctly:
RTNETLINK answers: Operation not supported
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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When accessing the SJA1000 controller registers in the indirect access mode,
writing the register number and reading/writing the data has to be an atomic
attempt.
As the sja1000_isa driver is an old style driver with a fixed number of
instances the locking variable depends on the same index like all the other
configuration elements given on the module command line.
As a positive side effect dev->dev_id is populated by the instance index,
which was missing in 3e66d0138c05d9 ("can: populate netdev::dev_id for udev
discrimination").
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Coverity complains that c_can_pci_probe() calls pci_enable_msi() without
checking the result:
CID 712278 (#1 of 1): Unchecked return value (CHECKED_RETURN) 3. check_return:
Calling pci_enable_msi_block without checking return value (as is done
elsewhere 88 out of 105 times).
88 pci_enable_msi(pdev);
This is CID 712278.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Reported-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Commit 6439fbce1075 (can: c_can: fix error checking of priv->instance in
probe()) found the warning but applied a suboptimal solution. Since, both
pdev->id and of_alias_get_id() return integers, it makes sense to convert the
variable to an integer and avoid the cast.
Signed-off-by: Wolfram Sang <wsa@sang-engineering.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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It's suffcient to kill the TXIE bit in the message control register
even if the documentation of C and D CAN says that it's not allowed to
do that while MSGVAL is set. Reality tells a different story and this
change gives us another 2% of CPU back for not waiting on I/O.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Mark suggested to use one IF for the softirq and the other for the
xmit function to avoid the xmit lock.
That requires to write the frame into the interface first, then handle
the echo skb and store the dlc before committing the TX request to the
message ram.
We use an atomic to handle the active buffers instead of reading the
MSGVAL register as thats way faster especially on PCH/x86.
Suggested-by: Mark <mark5@del-llc.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Instead of obfuscating the code by artificial 16 bit splits use the
proper 32 bit assignments and split the result when writing to the
interface.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Remove the MASK from the TX transfer side.
Make the code readable and get rid of the annoying IFX_WRITE_XXX_16BIT
macros which are just obfuscating the code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Sigh!
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Alexander reported that the new optimized handling of the RX fifo
causes random packet loss on Intel PCH C_CAN hardware.
After a few fruitless debugging sessions I got hold of a PCH (eg20t)
afflicted system. That machine does not have the CAN interface wired
up, but it was possible to reproduce the issue with the HW loopback
mode.
As Alexander observed correctly, clearing the NewDat flag along with
reading out the message buffer causes that issue on C_CAN, while D_CAN
handles that correctly.
Instead of restoring the original message buffer handling horror the
following workaround solves the issue:
transfer buffer to IF without clearing the NewDat
handle the message
clear NewDat bit
That's similar to the original code but conditional for C_CAN.
I really wonder why all user manuals (C_CAN, Intel PCH and some more)
recommend to clear the NewDat bit right away. The knows it all Oracle
operated by Gurgle does not unearth any useful information either. I
simply cannot believe that we are the first to uncover that HW issue.
Reported-and-tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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The RX buffer split causes packet loss in the hardware:
What happens is:
RX Packet 1 --> message buffer 1 (newdat bit is not cleared)
RX Packet 2 --> message buffer 2 (newdat bit is not cleared)
RX Packet 3 --> message buffer 3 (newdat bit is not cleared)
RX Packet 4 --> message buffer 4 (newdat bit is not cleared)
RX Packet 5 --> message buffer 5 (newdat bit is not cleared)
RX Packet 6 --> message buffer 6 (newdat bit is not cleared)
RX Packet 7 --> message buffer 7 (newdat bit is not cleared)
RX Packet 8 --> message buffer 8 (newdat bit is not cleared)
Clear newdat bit in message buffer 1
Clear newdat bit in message buffer 2
Clear newdat bit in message buffer 3
Clear newdat bit in message buffer 4
Clear newdat bit in message buffer 5
Clear newdat bit in message buffer 6
Clear newdat bit in message buffer 7
Clear newdat bit in message buffer 8
Now if during that clearing of newdat bits, a new message comes in,
the HW gets confused and drops it.
It does not matter how many of them you clear. I put a delay between
clear of buffer 1 and buffer 2 which was long enough that the message
should have been queued either in buffer 1 or buffer 9. But it did not
show up anywhere. The next message ended up in buffer 1. So the
hardware lost a packet of course without telling it via one of the
error handlers.
That does not happen on all clear newdat bit events. I see one of 10k
packets dropped in the scenario which allows us to reproduce. But the
trace looks always the same.
Not splitting the RX Buffer avoids the packet loss but can cause
reordering. It's hard to trigger, but it CAN happen.
With that mode we use the HW as it was probably designed for. We read
from the buffer 1 upwards and clear the buffer as we get the
message. That's how all microcontrollers use it. So I assume that the
way we handle the buffers was never really tested. According to the
public documentation it should just work :)
Let the user decide which evil is the lesser one.
[ Oliver Hartkopp: Provided a sane config option and help text and
made me switch to favour potential and unlikely reordering over
packet loss ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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The driver handles pointlessly TWO interrupts per packet. The reason
is that it enables the status interrupt which fires for each rx and tx
packet and it enables the per message object interrupts as well.
The status interrupt merily acks or in case of D_CAN ignores the TX/RX
state and then the message object interrupt fires.
The message objects interrupts are only useful if all message objects
have hardware filters activated.
But we don't have that and its not simple to implement in that driver
without rewriting it completely.
So we can ditch the message object interrupts and handle the RX/TX
right away from the status interrupt. Instead of TWO we handle ONE.
Note: We must keep the TXIE/RXIE bits in the message buffers because
the status interrupt alone is not reliable enough in corner cases.
If we ever have the need for HW filtering, then this code needs a
complete overhaul and we can think about it then. For now we prefer a
lower interrupt load.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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On D_CAN the RXOK, TXOK and LEC bits are cleared/set on read of the
status register. No need to update them.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Instead of writing to the message object we can simply clear the
NewDat bit with the get method.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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If the allocation of the error skb fails, we still want to see the
error statistics.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Reading the LEC type with
return (mode & ENABLED) && (status & LEC_MASK);
is not guaranteed to return (status & LEC_MASK) if the enabled bit in
mode is set. It's guaranteed to return 0 or !=0.
Remove the inline function and call unconditionally into the
berr_handling code and return early when the reporting is disabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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If the allocation of an error skb fails, the state change handling
returns w/o doing any work. That leaves the interface in a wreckaged
state as the internal status is wrong.
Split the interface handling and the skb handling.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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There is no guarantee that the skb is in the same state after calling
net_receive_skb(). 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.
The whole can subsystem is full of this. Copy and paste ....
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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The state change handler is called with device interrupts disabled
already. So no point in disabling them again when we enter bus off
state.
But what's worse is that we reenable the interrupts at the end of NAPI
poll unconditionally. So c_can_start() which is called from the
restart timer can trigger interrupts which confuse the hell out of the
half reinitialized driver/hw.
Remove the pointless device interrupt disable in the BUS_OFF handler
and prevent reenabling the device interrupts at the end of the poll
routine when the current state is BUS_OFF.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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c_can_start() enables interrupts way too early. The first enabling
happens when setting the control mode in c_can_chip_config() and then
again at the end of the function.
But that happens before napi_enable() and that means that an interrupt
which comes in will disable interrupts again and call napi_schedule,
which ignores the request and the later napi_enable() is not making
thinks work either. So the interface is up with all device interrupts
disabled.
Move the device interrupt after napi_enable() and add it to the other
callsites of c_can_start() in c_can_set_mode() and c_can_power_up()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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All type checks in c_can.c are != BOSCH_D_CAN so nobody noticed so far
that the pci code does not update the type information.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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The kernel oopses in phy_lookup() due to 'phy->init_data' being NULL if we
register PHYs from a device tree probing driver and then call phy_get() on a
device that has no representation in the device tree (e.g. a PCI device).
Checking the pointer before dereferening it and skipping an interation if
it's NULL prevents this kernel oops.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When OMAP_CONTROL_USB was renamed to OMAP_CONTROL_PHY (commit
14da699b), its dependencies were lost in the process. Nothing in the
commit message indicates that this removal was intentional, so I think
it was by accident and the dependencies should be restored.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Roger Quadros <rogerq@ti.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The top-level phy-samsung-usb2 driver may be configured as a
loadable module, which currently causes link errors because
of the dependency on the exynos{5250,4x12,4210}_usb2_phy_config
symbol. Solving this could be achieved by exporting these
symbols, but as the SoC-specific parts of the driver are not
currently built as modules, it seems better to just link
everything into one module and avoid the need for the export.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Fix driver new_id sysfs-attribute removal deadlock by making sure to
not hold any locks that the attribute operations grab when removing the
attribute.
Specifically, usb_serial_deregister holds the table mutex when
deregistering the driver, which includes removing the new_id attribute.
This can lead to a deadlock as writing to new_id increments the
attribute's active count before trying to grab the same mutex in
usb_serial_probe.
The deadlock can easily be triggered by inserting a sleep in
usb_serial_deregister and writing the id of an unbound device to new_id
during module unload.
As the table mutex (in this case) is used to prevent subdriver unload
during probe, it should be sufficient to only hold the lock while
manipulating the usb-serial driver list during deregister. A racing
probe will then either fail to find a matching subdriver or fail to get
the corresponding module reference.
Since v3.15-rc1 this also triggers the following lockdep warning:
======================================================
[ INFO: possible circular locking dependency detected ]
3.15.0-rc2 #123 Tainted: G W
-------------------------------------------------------
modprobe/190 is trying to acquire lock:
(s_active#4){++++.+}, at: [<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94
but task is already holding lock:
(table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (table_lock){+.+.+.}:
[<c0075f84>] __lock_acquire+0x1694/0x1ce4
[<c0076de8>] lock_acquire+0xb4/0x154
[<c03af3cc>] _raw_spin_lock+0x4c/0x5c
[<c02bbc24>] usb_store_new_id+0x14c/0x1ac
[<bf007eb4>] new_id_store+0x68/0x70 [usbserial]
[<c025f568>] drv_attr_store+0x30/0x3c
[<c01690e0>] sysfs_kf_write+0x5c/0x60
[<c01682c0>] kernfs_fop_write+0xd4/0x194
[<c010881c>] vfs_write+0xbc/0x198
[<c0108e4c>] SyS_write+0x4c/0xa0
[<c000f880>] ret_fast_syscall+0x0/0x48
-> #0 (s_active#4){++++.+}:
[<c03a7a28>] print_circular_bug+0x68/0x2f8
[<c0076218>] __lock_acquire+0x1928/0x1ce4
[<c0076de8>] lock_acquire+0xb4/0x154
[<c0166b70>] __kernfs_remove+0x254/0x310
[<c0167aa0>] kernfs_remove_by_name_ns+0x4c/0x94
[<c0169fb8>] remove_files.isra.1+0x48/0x84
[<c016a2fc>] sysfs_remove_group+0x58/0xac
[<c016a414>] sysfs_remove_groups+0x34/0x44
[<c02623b8>] driver_remove_groups+0x1c/0x20
[<c0260e9c>] bus_remove_driver+0x3c/0xe4
[<c026235c>] driver_unregister+0x38/0x58
[<bf007fb4>] usb_serial_bus_deregister+0x84/0x88 [usbserial]
[<bf004db4>] usb_serial_deregister+0x6c/0x78 [usbserial]
[<bf005330>] usb_serial_deregister_drivers+0x2c/0x4c [usbserial]
[<bf016618>] usb_serial_module_exit+0x14/0x1c [sierra]
[<c009d6cc>] SyS_delete_module+0x184/0x210
[<c000f880>] ret_fast_syscall+0x0/0x48
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(table_lock);
lock(s_active#4);
lock(table_lock);
lock(s_active#4);
*** DEADLOCK ***
1 lock held by modprobe/190:
#0: (table_lock){+.+.+.}, at: [<bf004d84>] usb_serial_deregister+0x3c/0x78 [usbserial]
stack backtrace:
CPU: 0 PID: 190 Comm: modprobe Tainted: G W 3.15.0-rc2 #123
[<c0015e10>] (unwind_backtrace) from [<c0013728>] (show_stack+0x20/0x24)
[<c0013728>] (show_stack) from [<c03a9a54>] (dump_stack+0x24/0x28)
[<c03a9a54>] (dump_stack) from [<c03a7cac>] (print_circular_bug+0x2ec/0x2f8)
[<c03a7cac>] (print_circular_bug) from [<c0076218>] (__lock_acquire+0x1928/0x1ce4)
[<c0076218>] (__lock_acquire) from [<c0076de8>] (lock_acquire+0xb4/0x154)
[<c0076de8>] (lock_acquire) from [<c0166b70>] (__kernfs_remove+0x254/0x310)
[<c0166b70>] (__kernfs_remove) from [<c0167aa0>] (kernfs_remove_by_name_ns+0x4c/0x94)
[<c0167aa0>] (kernfs_remove_by_name_ns) from [<c0169fb8>] (remove_files.isra.1+0x48/0x84)
[<c0169fb8>] (remove_files.isra.1) from [<c016a2fc>] (sysfs_remove_group+0x58/0xac)
[<c016a2fc>] (sysfs_remove_group) from [<c016a414>] (sysfs_remove_groups+0x34/0x44)
[<c016a414>] (sysfs_remove_groups) from [<c02623b8>] (driver_remove_groups+0x1c/0x20)
[<c02623b8>] (driver_remove_groups) from [<c0260e9c>] (bus_remove_driver+0x3c/0xe4)
[<c0260e9c>] (bus_remove_driver) from [<c026235c>] (driver_unregister+0x38/0x58)
[<c026235c>] (driver_unregister) from [<bf007fb4>] (usb_serial_bus_deregister+0x84/0x88 [usbserial])
[<bf007fb4>] (usb_serial_bus_deregister [usbserial]) from [<bf004db4>] (usb_serial_deregister+0x6c/0x78 [usbserial])
[<bf004db4>] (usb_serial_deregister [usbserial]) from [<bf005330>] (usb_serial_deregister_drivers+0x2c/0x4c [usbserial])
[<bf005330>] (usb_serial_deregister_drivers [usbserial]) from [<bf016618>] (usb_serial_module_exit+0x14/0x1c [sierra])
[<bf016618>] (usb_serial_module_exit [sierra]) from [<c009d6cc>] (SyS_delete_module+0x184/0x210)
[<c009d6cc>] (SyS_delete_module) from [<c000f880>] (ret_fast_syscall+0x0/0x48)
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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If no valid CHID value has previously been set on an HWA, writing a
value of all zeros will cause a kernel panic in uwb_radio_stop because
wusbhc->uwb_rc has not been set. This patch skips the call to
uwb_radio_stop if wusbhc->uwb_rc has not been initialized.
Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Nesting a spin_lock_irq/unlock_irq inside a lock that has already
disabled interrupts will enable interrupts before we are ready when
spin_unlock_irq is called. This patch converts the inner lock to use
spin_lock and spin_unlock instead.
Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This patch converts the use of spin_lock_irq/spin_unlock_irq to
spin_lock_irqsave/spin_unlock_irqrestore in uwb_rc_set_drp_cmd_done
which is called from a USB completion handler. There are also
whitespace cleanups to make checkpatch.pl happy.
Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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For internal PHY (like UTMI), the phy clock may from internal pll,
it is on/off on the fly, the access PORTSC.PTS will hang without
phy clock. So, the usb_phy_init which will open phy clock needs to
be called before hw_phymode_configure.
See: http://marc.info/?l=linux-arm-kernel&m=139350618732108&w=2
For external PHY (like ulpi), it needs to configure portsc.pts before
visit viewport, or the viewport can't be visited. so phy_phymode_configure
needs to be called before usb_phy_init.
See: cd0b42c2a6d2a74244f0053f8960f5dad5842278
It may not the best solution, but it can work for all situations.
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Cc: shc_work@mail.ru
Cc: denis@eukrea.com
Cc: festevam@gmail.com
Cc: stable <stable@vger.kernel.org> # 3.14
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-linus
Felipe writes:
usb: fixes for v3.15-rc3
Quite a few fixes this time since I lost v3.15-rc2
window.
Most fixes are MUSB which learned to remove its debugfs directories
properly, got a fix for PHY handling and now knows that it should
make sure its clocks aren't gated before trying to access registers.
ffs got a race fix between ffs_epfile_io() and ffs_func_eps_disable().
dwc3 got a fix for system suspend/resume and now only iterates over
valid endpoints when trying to resize TX fifos.
usb_get_phy() now will properly return an error if try_module_get() fails.
We also have a revert for a NAPI conversion on the ethernet gadget which
was causing a kernel BUG.
Signed-of-by: Felipe Balbi <balbi@ti.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fixes from Mark Brown:
"A couple of things here:
- Fixes for pbias that didn't make it in during the merge window due
to the driver coming in via MMC. The conversion to use helpers is
a fix as it implements list_voltage() which the main user (MMC)
relies on for correct functioning.
- Change the !REGULATOR stub for optional regulators to return an
error rather than a dummy; this is more in keeping with the
intended use of optional regulators and fixes some issues seen MMC
where it got confused by a dummy being provided"
* tag 'regulator-v3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: core: Return error in get optional stub
regulator: pbias: Convert to use regmap helper functions
regulator: pbias: Fix is_enabled callback implementation
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git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A few driver specific fixes here:
- SH HSPI was dealing with its clocks incorrectly which meant it
didn't work on some SoCs, fixing this also requires a small fix to
one of the SoC clock trees to avoid breaking existing users.
- The SiRF driver appears to have had several quality problems, it's
fairly new and not widely used so this isn't too worrying.
- A brute force fix for excessive locking in the Atmel driver, it
needs further investigation but this deals with the immediate
issue.
- A build fix for the Blackfin driver"
* tag 'spi-v3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: atmel: Fix scheduling while atomic bug
spi: sh-hspi: Do not specifically request shyway_clk clock
ARM: shmobile: r8a7778: Use clks as MSTP007 parent
spi: sirf: make GPIO chipselect function work well
spi: sirf: set SPI controller in RISC IO chipselect mode
spi: sirf: correct TXFIFO empty interrupt status bit
spi: bfin5xx: fix build error
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It is possible by passing a netlink socket to a more privileged
executable and then to fool that executable into writing to the socket
data that happens to be valid netlink message to do something that
privileged executable did not intend to do.
To keep this from happening replace bare capable and ns_capable calls
with netlink_capable, netlink_net_calls and netlink_ns_capable calls.
Which act the same as the previous calls except they verify that the
opener of the socket had the desired permissions as well.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This fixes a seg fault on 'ethtool -A' entry if the
interface is down. Obviously we need to have the
phy device initialized / "connected" (see of_phy_connect())
to be able to advertise pause frame capabilities.
Fixes: 23402bddf9e56eecb27bbd1e5467b3b79b3dbe58
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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o In case QLC_83XX_MBX_CMD_NO_WAIT command type the calling
function does not free the memory as it does not wait for
response. So free it when get a response from adapter after
sending the command.
Signed-off-by: Rajesh Borundia <rajesh.borundia@qlogic.com>
Signed-off-by: Shahed Shaikh <shahed.shaikh@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Some firmware versions fails to reset the lock during
initialization. Force reset firmware API lock during driver
probe to ensure lock availability.
Signed-off-by: Sony Chacko <sony.chacko@qlogic.com>
Signed-off-by: Shahed Shaikh <shahed.shaikh@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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