Peter Hurley [Thu, 22 Jan 2015 17:24:31 +0000 (12:24 -0500)]
serial: 8250: Prevent concurrent updates to shadow registers
The port shadow registers, ->fcr and ->mcr, must be protected from
concurrent updates. Relocate the shadow register updates in
serial8250_do_set_termios() to the port lock critical section.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Thu, 22 Jan 2015 17:24:30 +0000 (12:24 -0500)]
serial: 8250: Use canary to restart console after suspend
When using no_console_suspend, the serial console may be powered off
anyway during system sleep. Upon resume, the port may be in its default
power-on state, but is expected to continue console i/o before the device
has received its pm callback. The resultant garbage i/o can cause all
kinds of havoc on the remote end.
Use the scratch register as a canary to discover if the console
has been powered-off. Write a non-zero value to the scratch register
at port suspend and reprogram the port before any console i/o if the
scratch register != canary before port resume.
This workaround is disabled for omap_8250 (which uses different divisor
programming).
Credit to Doug Anderson <dianders@chromium.org> for the idea of using
the scratch register canary to discover port power-down.
Cc: Doug Anderson <dianders@chromium.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Exar XR17V35X PCIe uarts support a 4-bit fractional divisor register.
Refactor the divisor calculation from the divisor programming.
Allow a fractional result from serial8250_get_divisor() and pass this
result to serial8250_dl_write().
Simplify the calculation for quot and quot_frac. This was verified
to be identical to the results of the original calculation with a test
jig.
NB: The results were also compared with the divisor value chart
on pg 33 of the Exar XR17V352 datasheet, rev 1.0.3, here:
http://www.exar.com/common/content/document.ashx?id=1585
which differs from the calculated values by 1 in the fractional result.
This is because the calculated values are still rounded in the
fractional result, whereas the table values are truncated. Note
that the data error rate % values in the datasheet are for
rounded fractional results, as the truncated fractional results
have more error.
Cc: Joe Schultz <jschultz@xes-inc.com> Cc: Aaron Sierra <asierra@xes-inc.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Thu, 22 Jan 2015 17:24:28 +0000 (12:24 -0500)]
serial: 8250: Refactor divisor programming
Refactor divisor register programming into a new function,
serial8250_set_divisor; this allows serial console to reinitialize
early after resume from suspend.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Thu, 22 Jan 2015 17:24:26 +0000 (12:24 -0500)]
serial: 8250: Move UART_BUG_QUOT workaround
The UART_BUG_QUOT workaround adjusts the divisor computed from the
baud rate by serial8250_get_divisor(). Move the workaround into
serial8250_get_divisor(), so that divisor-from-baud computation
is encapsulated.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: men_z135_uart: Fix driver for changes in hardware
16z135 IP Core has changed so the driver needs to be updated to respect
these changes. The following changes have been made:
* Don't invert the 16z135 modem status register when reading.
* Add module parameter to configure the (baud rate dependent) RX timeout.
Character timeout in seconds = (timeout_reg * baud_reg * 4)/freq_reg.
* Enable the handling of UART core's automatic flow control feature.
When AFE is active disable generation of modem status IRQs.
* Rework the handling of IRQs to be conform with newer FPGA versions and
take precautions not to miss an interrupt because of the destructive read
of the IIR register.
* Correct men_z135_handle_modem_status(), MSR is stat_reg[15:8] not
stat_reg[7:0]
* Correct calling of uart_handle_{dcd,cts}_change()
* Reset CLOCAL when CRTSCTS is set
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@men.de> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Thu, 22 Jan 2015 17:24:25 +0000 (12:24 -0500)]
serial: core: Simplify console suspend logic in uart_suspend_port()
When the uart port being suspended is a console and consoles are
not suspending (kernel command line contains no_console_suspend),
then no action is performed for that port, and the function can
return early.
If the function has not returned early, then one of the conditions
is not true, so the expression
(console_suspend_enabled || !uart_console(uport))
must be true and can be eliminated.
Similarly, the expression
(console_suspend_enabled && uart_console(uport))
simplifies to just uart_console(uport).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for specifying PCI based UARTs for earlyprintk
using a syntax like "earlyprintk=pciserial,00:18.1,115200",
where 00:18.1 is the BDF of a UART device.
[Slightly tidied from Stuart's original patch] Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Sat, 17 Jan 2015 20:42:06 +0000 (15:42 -0500)]
n_tty: Fix signal handling flushes
BRKINT and ISIG requires input and output flush when a signal char
is received. However, the order of operations is significant since
parallel i/o may be ongoing.
Merge the signal handling for BRKINT with ISIG handling.
Process the signal first. This ensures any ongoing i/o is aborted;
without this, a waiting writer may continue writing after the flush
occurs and after the signal char has been echoed.
Write lock the termios_rwsem, which excludes parallel writers from
pushing new i/o until after the output buffers are flushed; claiming
the write lock is necessary anyway to exclude parallel readers while
the read buffer is flushed.
Subclass the termios_rwsem for ptys since the slave pty performing
the flush may appear to reorder the termios_rwsem->tty buffer lock
lock order; adding annotation clarifies that
slave tty_buffer lock-> slave termios_rwsem -> master tty_buffer lock
is a valid lock order.
Flush the echo buffer. In this context, the echo buffer is 'output'.
Otherwise, the output will appear discontinuous because the output buffer
was cleared which contains older output than the echo buffer.
Open-code the read buffer flush since the input worker does not need
kicking (this is the input worker).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Sat, 17 Jan 2015 20:42:05 +0000 (15:42 -0500)]
pty: Fix buffer flush deadlock
The pty driver does not clear its write buffer when commanded.
This is to avoid an apparent deadlock between parallel flushes from
both pty ends; specifically when handling either BRK or INTR input.
However, parallel flushes from this source is not possible since
the pty master can never be set to BRKINT or ISIG. Parallel flushes
from other sources are possible but these do not threaten deadlocks.
Annotate the tty buffer mutex for lockdep to represent the nested
tty_buffer locking which occurs when the pty slave is processing input
(its buffer mutex held) and receives INTR or BRK and acquires the
linked tty buffer mutex via tty_buffer_flush().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Fri, 16 Jan 2015 20:05:39 +0000 (15:05 -0500)]
n_tty: Fix read buffer overwrite when no newline
In canon mode, the read buffer head will advance over the buffer tail
if the input > 4095 bytes without receiving a line termination char.
Discard additional input until a line termination is received.
Before evaluating for overflow, the 'room' value is normalized for
I_PARMRK and 1 byte is reserved for line termination (even in !icanon
mode, in case the mode is switched). The following table shows the
transform:
actual buffer | 'room' value before overflow calc
space avail | !I_PARMRK | I_PARMRK
--------------------------------------------------
0 | -1 | -1
1 | 0 | 0
2 | 1 | 0
3 | 2 | 0
4+ | 3 | 1
When !icanon or when icanon and the read buffer contains newlines,
normalized 'room' values of -1 and 0 are clamped to 0, and
'overflow' is 0, so read_head is not adjusted and the input i/o loop
exits (setting no_room if called from flush_to_ldisc()). No input
is discarded since the reader does have input available to read
which ensures forward progress.
When icanon and the read buffer does not contain newlines and the
normalized 'room' value is 0, then overflow and room are reset to 1,
so that the i/o loop will process the next input char normally
(except for parity errors which are ignored). Thus, erasures, signalling
chars, 7-bit mode, etc. will continue to be handled properly.
If the input char processed was not a line termination char, then
the canon_head index will not have advanced, so the normalized 'room'
value will now be -1 and 'overflow' will be set, which indicates the
read_head can safely be reset, effectively erasing the last char
processed.
If the input char processed was a line termination, then the
canon_head index will have advanced, so 'overflow' is cleared to 0,
the read_head is not reset, and 'room' is cleared to 0, which exits
the i/o loop (because the reader now have input available to read
which ensures forward progress).
Note that it is possible for a line termination to be received, and
for the reader to copy the line to the user buffer before the
input i/o loop is ready to process the next input char. This is
why the i/o loop recomputes the room/overflow state with every
input char while handling overflow.
Finally, if the input data was processed without receiving
a line termination (so that overflow is still set), the pty
driver must receive a write wakeup. A pty writer may be waiting
to write more data in n_tty_write() but without unthrottling
here that wakeup will not arrive, and forward progress will halt.
(Normally, the pty writer is woken when the reader reads data out
of the buffer and more space become available).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Fri, 16 Jan 2015 20:05:38 +0000 (15:05 -0500)]
n_tty: Fix PARMRK over-throttling
If PARMRK is enabled, the available read buffer space computation is
overly-pessimistic, which results in severely throttled i/o, even
in the absence of parity errors. For example, if the 4k read buffer
contains 1k processed data, the input worker will compute available
space of 333 bytes, despite 3k being available. At 1365 chars of
processed data, 0 space available is computed.
*Divide remaining space* by 3, truncating down (if left == 2, left = 0).
Reported-by: Christian Riesch <christian.riesch@omicron.at>
Conflicts:
drivers/tty/n_tty.c
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Fri, 16 Jan 2015 20:05:37 +0000 (15:05 -0500)]
n_tty: Fix unordered accesses to lockless read buffer
Add commit_head buffer index, which the producer-side publishes
after input processing in non-canon mode. This ensures the consumer-side
observes correctly-ordered writes in non-canonical mode (ie., the buffer
data is written before the buffer index is advanced). Fix consumer-side
uses of read_cnt() to use commit_head instead.
Add required memory barriers to the tail index to guarantee
the consumer-side has completed the loads before the producer-side
begins writing new data. Open-code the producer-side receive_room()
into the i/o loop.
Remove no-longer-referenced receive_room().
Based on work by Christian Riesch <christian.riesch@omicron.at>
Cc: Christian Riesch <christian.riesch@omicron.at> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Fri, 16 Jan 2015 20:05:36 +0000 (15:05 -0500)]
n_tty: Simplify throttle threshold calculation
The adjustments performed by receive_room() are to ensure a line
termination can always be written to the read buffer. However,
these adjustments are irrelevant to the throttle threshold (because
the threshold < buffer limit).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Fri, 16 Jan 2015 20:05:35 +0000 (15:05 -0500)]
n_tty: Fix throttle for canon lines > 3967 chars
The tty driver will be mistakenly throttled if a line termination
has not been received, and the line exceeds 3967 chars. Thus, it is
possible for the driver to stop sending when it has not yet sent
the newline. This does not apply to the pty driver.
Don't throttle until at least one line termination has been
received.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Fri, 16 Jan 2015 20:05:34 +0000 (15:05 -0500)]
n_tty: Eliminate receive_room() from consumer/exclusive paths
The input worker never reschedules itself; it only processes input until
either there is no more input or the read buffer is full. So the reader
is responsible for restarting the input worker only if the read buffer
was previously full (no_room == 1) _and_ space is now available to process
more input because the reader has consumed data from the read buffer.
However, computing the actual space available is not required to determine
if the reader has consumed data from the read buffer. This condition is
evaluated in 5 situations, each of which the space avail is already known:
1. n_tty_flush_buffer() - the read buffer is empty; kick the worker
2. n_tty_set_termios() - no data has been consumed; do not kick the worker
(although it may have kicked the reader so data _will be_ consumed)
3. n_tty_check_unthrottle - avail space > 3968; kick the worker
4. n_tty_read, before leaving - only kick the worker if the reader has
moved the tail. This prevents unnecessarily kicking the worker
when timeout-style reading is used.
5. n_tty_read, before sleeping - although it is possible for the read
buffer to be full and input_available_p() to be false, this can
only happen when the input worker is racing the reader, in which
case the reader will have been woken and won't sleep.
Rename n_tty_set_room() to n_tty_kick_worker() to reflect what the
function actually does.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tomasz Figa [Fri, 23 Jan 2015 13:47:42 +0000 (14:47 +0100)]
ARM: dts: exynos4: Add stdout-path properties
This patch adds stdout-path property to chosen nodes of Exynos4 boards
to enable use of earlycon feature without the need to hardcode port
number in kernel itself.
Signed-off-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tomasz Figa [Fri, 23 Jan 2015 13:47:41 +0000 (14:47 +0100)]
serial: samsung: Add support for early console
This patch adds support for early console initialized from device tree
and kernel command line to all variants of Samsung serial driver.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
[mszyprow: added support for command line based initialization,
fixed comments, added documentation] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com> Tested-by: Alim Akhtar <alim.akhtar@samsung.com> Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Hisashi Nakamura [Mon, 26 Jan 2015 12:25:48 +0000 (21:25 +0900)]
serial: sh-sci: Fix R-Car SCIF and HSCIF overrun handling
When fifo overrun happened, the interrupt status refers to
SCLSR register in R-Car SCIF and HSCIF.
Thus, overrun handling takes SCLSR register into account.
Yoshihiro Kaneko [Mon, 26 Jan 2015 11:53:29 +0000 (20:53 +0900)]
serial: sh-sci: Use dev_dbg() to log an error message
Since the driver cannot return from overrun error if characters
are output during overrun process, use dev_dbg() instead of
dev_notice() to log the error message of overrun in syslog.
Sergei Shtylyov [Fri, 16 Jan 2015 21:56:02 +0000 (13:56 -0800)]
sh-sci: extend PM methods
In order to make it possible to restore from hibernation not only in Linux but
also in e.g. U-Boot, we have to use sci_{suspend|remove}() for the PM {freeze|
thaw|restore}() methods. It's handy to achieve this by using SIMPLE_DEV_PM_OPS()
macro, however we have to annotate sci_{suspend|remove}() with '__maybe_unused'
in order to avoid compilation warnings when CONFIG_PM_SLEEP is undefined.
Based on orignal patch by Mikhail Ulyanov <mikhail.ulyanov@cogentembedded.com>.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nathan Rossi [Fri, 16 Jan 2015 12:49:25 +0000 (13:49 +0100)]
tty: xuartps: Fix RX hang, and TX corruption in termios call
The implementation of flushing the RX FIFO breaks in a number of cases,
it is impossible to ensure an complete flush of the RX FIFO due to the
hardware not allowing the use of the FIFOs when the receiver is disabled
(Reading from the FIFO register does not remove it from the FIFO when
the RX_EN=0 or RX_DIS=1). Additionally during an initial set_termios
call where RX_DIS=1 causes a hang waiting forever for the RX FIFO to
empty. On top of this the FIFO will be cleared by the use of the RXRST
bits on the Control Register, making the RX flush pointless (as it does
not preserve the data read anyway).
Due to the TXRST the TX FIFO and transmitter can be interrupted during
frame trasmission, causing corruption and additionally data lost in the
FIFO. Most other serial drivers do not flush or clear the FIFOs during
a termios configuration change and as such do not have issues with
corruption. For this UART controller is it required that the TXRST/RXRST
bit be flagged during the change, this means that the data in the FIFO
will be dropped when changing configuration. In order to prevent data
loss and corruption of the transmitted data, wait until the TX FIFO is
empty before changing the configuration. The performance of this may
cause the set_termios call to take a longer amount of time especially
on lower baud rates, however it is comparable to the same performance
hit that a console_write call costs.
Arnd Bergmann [Tue, 13 Jan 2015 21:59:47 +0000 (22:59 +0100)]
tty/isicom: fix big-endian compile warning
Building an arm allmodconfig kernel triggers a lengthy but harmless
warning in the isicom driver:
drvers/tty/isicom.c: In function 'isicom_send_break':
uapi/linux/swab.h:13:15: warning: integer overflow in expression [-Woverflow]
(((__u16)(x) & (__u16)0x00ffU) << 8) | \
^
uapi/linux/swab.h:107:2: note: in expansion of macro '___constant_swab16'
___constant_swab16(x) : \
^
uapi/linux/byteorder/big_endian.h:34:43: note: in expansion of macro '__swab16'
#define __cpu_to_le16(x) ((__force __le16)__swab16((x)))
^
linux/byteorder/generic.h:89:21: note: in expansion of macro '__cpu_to_le16'
#define cpu_to_le16 __cpu_to_le16
^
include/asm/io.h:270:6: note: in expansion of macro 'cpu_to_le16'
cpu_to_le16(v),__io(p)); })
^
drivers/tty/isicom.c:1058:2: note: in expansion of macro 'outw'
outw((length & 0xff00), base);
^
Apparently, the problem is related to the fact that the value 0xff00,
when used as a 16-bit number, is negative and passed into bitwise
operands of the generic byte swapping code.
Marking the input argument as unsigned in both technically correct
and avoids the warning.
Baruch Siach [Wed, 14 Jan 2015 06:04:21 +0000 (08:04 +0200)]
tty/serial: digicolor: remove sysrq reference
The Digicolor USART hardware does not support detecting the BREAK condition.
This means that we can't support sysrq on this hardware. Remove all reference
to sysrq from the code.
This also fixes build when sysrq is disabled:
drivers/tty/serial/digicolor-usart.c: In function 'digicolor_uart_console_write':
drivers/tty/serial/digicolor-usart.c:407:33: error: 'struct uart_port' has no member named 'sysrq'
Peter Hurley [Thu, 22 Jan 2015 16:50:25 +0000 (11:50 -0500)]
serial: 8250_pnp: Enable PNP_CONSOLE for console ports
When the kernel command line parameter, no_console_suspend, is used,
the console should continue to output console messages during and
after system suspend. For a serial console, the serial core ensures
that the device is not shutdown when no_console_suspend is specified.
However, the default operation of the pnp bus will disable and suspend
the device and no further output occurs.
When registering the 8250 port, if the serial device is a console
set the PNP_CONSOLE capability, which prevents device power-off
if consoles are not suspending.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley [Thu, 22 Jan 2015 16:50:24 +0000 (11:50 -0500)]
PNP: Allow console to override ACPI device sleep
If the serial console is an ACPI PNP device, the PNP bus always powers
down the device at system suspend, even though the no_console_suspend
command line parameter is specified (eg., when debugging suspend/resume).
Add PNP_CONSOLE capability, which when set, prevents calling both the
->disable() and ->suspend() PNP protocol methods if console suspend
is disabled.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pramod Gurav [Mon, 12 Jan 2015 13:45:32 +0000 (19:15 +0530)]
tty: serial: msm_serial: code cleanup in msm_console_setup
The change does following:
- baud, flow, bits, parity were being overwritten as they were
being reinitialized after parsing. Initialize them when they are
declared so that user provided setting are not overwritten.
- msm_set_baud_rate() is anyway called in uart_set_options when it calls
msm_set_termios(). msm_reset() is called when we change the baud rate.
Hence doing away with both of these calls.
- CR_CMD_PROTECTION_EN and CR_TX_ENABLE settings are done in msm_set_baud_rate.
So do away with this here.
Andy Shevchenko [Mon, 12 Jan 2015 13:17:22 +0000 (15:17 +0200)]
x86, mrst: remove Moorestown specific serial drivers
Intel Moorestown platform support was removed few years ago. This is a follow
up which removes Moorestown specific code for the serial devices. It includes
mrst_max3110 and earlyprintk bits.
This was used on SFI (Medfield, Clovertrail) based platforms as well, though
new ones use normal serial interface for the console service.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: David Cohen <david.a.cohen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stefan Agner [Mon, 26 Jan 2015 00:10:16 +0000 (01:10 +0100)]
tty: serial: fsl_lpuart: terminate DMA on buffer flush
On uart buffer flush, serial core resets the circular buffer.
If a DMA transfer is in progress at that time, the callback
lpuart_dma_tx_complete will move buffer's tail unconditionally,
hence tail moves beyond head. Use the flush_buffer hook to
terminate the DMA imeaditely and avoid lpuart_dma_tx_complete
being called in this situation.
This bug often showed up while shutdown and lead to duplicate
serial console output.
Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stefan Agner [Sat, 10 Jan 2015 08:33:46 +0000 (09:33 +0100)]
serial: fsl_lpuart: update RX timer on successful DMA transfer
To end a DMA transfer which did not consume a whole buffer (e.g. one
character only), a RX timer is used. When lots of data are received
the DMA transfer will complete and setup another DMA transfer, which
in turn might complete again. In this cases, it is not necessary to
abort the DMA transfers using the RX timer. This change pushes the
RX timer timeout into the future each time a DMA transfer completed.
Aborting the DMA was not very harmful, since the next received
character lead to setup of another RX DMA.
Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stefan Agner [Sat, 10 Jan 2015 08:33:45 +0000 (09:33 +0100)]
serial: fsl_lpuart: move DMA channel request to probe
Move the DMA channel request to probe to avoid requesting the DMA
channel on each opening of the ttyLPx device. This also fixes a
potential issue that TX channel is not freed when only RX channel
allocation fails. The DMA channels are now handled independently,
so one could use UART with DMA only in TX direction for instance.
Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stefan Agner [Sat, 10 Jan 2015 00:08:59 +0000 (01:08 +0100)]
serial: fsl_lpuart: avoid new transfer while DMA is running
When the UART is in DMA receive mode (RDMAS set) and one character
just arrived while another interrupt is handled (e.g. TX), the RDRF
(receiver data register full flag) is set due to the water level of
1. But since the DMA will take care of this character, there is no
need to handle it by calling lpuart_prepare_rx. Handling it leads to
adding the RX timeout timer twice:
[ 74.336698] Kernel BUG at 80053070 [verbose debug info unavailable]
[ 74.342999] Internal error: Oops - BUG: 0 [#1] ARM0:00.00 khungtaskd
[ 74.347817] Modules linked in: 0 S 0.0 0.0 0:00.00 writeback
[ 74.350926] CPU: 0 PID: 0 Comm: swapper Not tainted 3.19.0-rc3-00001-g39d78e2 #1788
[ 74.358617] Hardware name: Freescale Vybrid VF610 (Device Tree)t
[ 74.364563] task: 807a7678 ti: 8079c000 task.ti: 8079c000 kblockd
[ 74.370002] PC is at add_timer+0x24/0x28.0 0.0 0:00.09 kworker/u2:1
[ 74.373960] LR is at lpuart_int+0x15c/0x3d8
[ 74.378171] pc : [<80053070>] lr : [<802e0d88>] psr: a0010193
[ 74.378171] sp : 8079de10 ip : 8079de20 fp : 8079de1c
[ 74.389694] r10: 807d44c0 r9 : 8688c300 r8 : 00000013
[ 74.394943] r7 : 20010193 r6 : 00000000 r5 : 000000a0 r4 : 86997210
[ 74.401498] r3 : ffffa7da r2 : 80817868 r1 : 86997210 r0 : 86997344
[ 74.408052] Flags: NzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel
[ 74.415489] Control: 10c5387d Table: 8611c059 DAC: 00000015
[ 74.421265] Process swapper (pid: 0, stack limit = 0x8079c230)
...
Solve this by only execute the receiver path (lpuart_prepare_rx) if
the DMA receive mode (RDMAS) is not set. Also, make sure the flag is
cleared on initialization, in case it has been left set.
This can be best reproduced using UART as a serial console, then
running top while dd'ing data into the terminal.
Stefan Agner [Sat, 10 Jan 2015 00:08:58 +0000 (01:08 +0100)]
serial: fsl_lpuart: delete timer on shutdown
If the serial port gets closed while a RX transfer is in progress,
the timer might fire after the serial port shutdown finished. This
leads in a NULL pointer dereference:
[ 7.508324] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[ 7.516590] pgd = 86348000
[ 7.519445] [00000000] *pgd=86179831, *pte=00000000, *ppte=00000000
[ 7.526145] Internal error: Oops: 17 [#1] ARM
[ 7.530611] Modules linked in:
[ 7.533876] CPU: 0 PID: 123 Comm: systemd Not tainted 3.19.0-rc3-00004-g5b11ea7 #1778
[ 7.541827] Hardware name: Freescale Vybrid VF610 (Device Tree)
[ 7.547862] task: 861c3400 ti: 86ac8000 task.ti: 86ac8000
[ 7.553392] PC is at lpuart_timer_func+0x24/0xf8
[ 7.558127] LR is at lpuart_timer_func+0x20/0xf8
[ 7.562857] pc : [<802df99c>] lr : [<802df998>] psr: 600b0113
[ 7.562857] sp : 86ac9b90 ip : 86ac9b90 fp : 86ac9bbc
[ 7.574467] r10: 80817180 r9 : 80817b98 r8 : 80817998
[ 7.579803] r7 : 807acee0 r6 : 86989000 r5 : 00000100 r4 : 86997210
[ 7.586444] r3 : 86ac8000 r2 : 86ac9bc0 r1 : 86997210 r0 : 00000000
[ 7.593085] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
[ 7.600341] Control: 10c5387d Table: 86348059 DAC: 00000015
[ 7.606203] Process systemd (pid: 123, stack limit = 0x86ac8230)
Setup the timer on UART startup which allows to delete the timer
unconditionally on shutdown. This also saves the initialization
on each transfer.
Peter Hurley [Mon, 19 Jan 2015 18:05:03 +0000 (13:05 -0500)]
tty: Prevent untrappable signals from malicious program
Commit 26df6d13406d1a5 ("tty: Add EXTPROC support for LINEMODE")
allows a process which has opened a pty master to send _any_ signal
to the process group of the pty slave. Although potentially
exploitable by a malicious program running a setuid program on
a pty slave, it's unknown if this exploit currently exists.
Limit to signals actually used.
Cc: Theodore Ts'o <tytso@mit.edu> Cc: Howard Chu <hyc@symas.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Cc: <stable@vger.kernel.org> # 2.6.36+ Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nicolas Pitre [Fri, 23 Jan 2015 22:07:21 +0000 (17:07 -0500)]
vt: provide notifications on selection changes
The vcs device's poll/fasync support relies on the vt notifier to signal
changes to the screen content. Notifier invocations were missing for
changes that comes through the selection interface though. Fix that.
Tested with BRLTTY 5.2.
Signed-off-by: Nicolas Pitre <nico@linaro.org> Cc: Dave Mielke <dave@mielke.cc> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linus Torvalds [Sun, 18 Jan 2015 06:00:40 +0000 (18:00 +1200)]
Merge tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"We've been sitting on our fixes branch for a while, so this batch is
unfortunately on the large side.
A lot of these are tweaks and fixes to device trees, fixing various
bugs around clocks, reg ranges, etc. There's also a few defconfig
updates (which are on the late side, no more of those).
All in all the diffstat is bigger than ideal at this time, but nothing
in here seems particularly risky"
* tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (31 commits)
reset: sunxi: fix spinlock initialization
ARM: dts: disable CCI on exynos5420 based arndale-octa
drivers: bus: check cci device tree node status
ARM: rockchip: disable jtag/sdmmc autoswitching on rk3288
ARM: nomadik: fix up leftover device tree pins
ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree
ARM: at91/dt: sam9263: Add missing clocks to lcdc node
ARM: at91: sama5d3: dt: correct the sound route
ARM: at91/dt: sama5d4: fix the timer reg length
ARM: exynos_defconfig: Enable LM90 driver
ARM: exynos_defconfig: Enable options for display panel support
arm: dts: Use pmu_system_controller phandle for dp phy
ARM: shmobile: sh73a0 legacy: Set .control_parent for all irqpin instances
ARM: dts: berlin: correct BG2Q's SM GPIO location.
ARM: dts: berlin: add broken-cd and set bus width for eMMC in Marvell DMP DT
ARM: dts: berlin: fix io clk and add missing core clk for BG2Q sdhci2 host
ARM: dts: Revert disabling of smc91x for n900
ARM: dts: imx51-babbage: Fix ULPI PHY reset modelling
ARM: dts: dra7-evm: fix qspi device tree partition size
ARM: omap2plus_defconfig: use CONFIG_CPUFREQ_DT
...
Linus Torvalds [Sun, 18 Jan 2015 03:29:11 +0000 (15:29 +1200)]
Merge tag 'clk-fixes-for-linus' of git://git.linaro.org/people/mike.turquette/linux
Pull clock driver fixes from Mike Turquette:
"Small number of fixes for clock drivers and a single null pointer
dereference fix in the framework core code.
The driver fixes vary from fixing section mismatch warnings to
preventing machines from hanging (and preventing developers from
crying)"
* tag 'clk-fixes-for-linus' of git://git.linaro.org/people/mike.turquette/linux:
clk: fix possible null pointer dereference
Revert "clk: ppc-corenet: Fix Section mismatch warning"
clk: rockchip: fix deadlock possibility in cpuclk
clk: berlin: bg2q: remove non-exist "smemc" gate clock
clk: at91: keep slow clk enabled to prevent system hang
clk: rockchip: fix rk3288 cpuclk core dividers
clk: rockchip: fix rk3066 pll lock bit location
clk: rockchip: Fix clock gate for rk3188 hclk_emem_peri
clk: rockchip: add CLK_IGNORE_UNUSED flag to fix rk3066/rk3188 USB Host
Linus Torvalds [Sun, 18 Jan 2015 03:26:52 +0000 (15:26 +1200)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"This is one fix for a Multiqueue sleeping in invalid context problem
and a MAINTAINER file update for Qlogic"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ->queue_rq can't sleep
MAINTAINERS: Update maintainer list for qla4xxx
The commit 646cafc6 (clk: Change clk_ops->determine_rate to
return a clk_hw as the best parent) opens a possibility for
null pointer dereference, fix this.
Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
That commit tried to fix the section mismatch warning by moving the
ppc_corenet_clk_driver struct to init section. This is definitely wrong
because the kernel would free the memories occupied by this struct
after boot while this driver is still registered in the driver core.
The kernel would panic when accessing this driver struct.
Cc: stable@vger.kernel.org # 3.17 Signed-off-by: Kevin Hao <haokexin@gmail.com> Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Michael Turquette <mturquette@linaro.org>
Linus Torvalds [Sat, 17 Jan 2015 18:26:24 +0000 (06:26 +1200)]
Merge branch 'fixes' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fixes from Vinod Koul:
"Two patches, the first by Andy to fix dw dmac runtime pm and second
one by me to fix the dmaengine headers in MAINTAINERS"
* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: dw: balance PM runtime calls
MAINTAINERS: dmaengine: fix the header file for dmaengine
Linus Torvalds [Sat, 17 Jan 2015 18:24:30 +0000 (06:24 +1200)]
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, but also two PMU driver fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf tools powerpc: Use dwfl_report_elf() instead of offline.
perf tools: Fix segfault for symbol annotation on TUI
perf test: Fix dwarf unwind using libunwind.
perf tools: Avoid build splat for syscall numbers with uclibc
perf tools: Elide strlcpy warning with uclibc
perf tools: Fix statfs.f_type data type mismatch build error with uclibc
tools: Remove bitops/hweight usage of bits in tools/perf
perf machine: Fix __machine__findnew_thread() error path
perf tools: Fix building error in x86_64 when dwarf unwind is on
perf probe: Propagate error code when write(2) failed
perf/x86/intel: Fix bug for "cycles:p" and "cycles:pp" on SLM
perf/rapl: Fix sysfs_show() initialization for RAPL PMU
Olof Johansson [Thu, 15 Jan 2015 23:45:18 +0000 (15:45 -0800)]
Merge tag 'samsung-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into fixes
Merge "Samsung fixes for v3.19" from Kukjin Kim:
Samsung fixes for v3.19
- exynos_defconfig: enable LM90 driver and display panel support
- HWMON
- SENSORS_LM90
- Direct Rendering Manager (DRM)
- DRM bridge registration and lookup framework
- Parade ps8622/ps8625 eDP/LVDS bridge
- NXP ptn3460 eDP/LVDS bridge
- Exynos Fully Interactive Mobile Display controller (FIMD)
- Panel registration and lookup framework
- Simple panels
- Backlight & LCD device support
- use pmu_system_controller phandle for dp phy
: DP PHY requires pmu_system_controller to handle PMU reg. now
* tag 'samsung-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
ARM: exynos_defconfig: Enable LM90 driver
ARM: exynos_defconfig: Enable options for display panel support
arm: dts: Use pmu_system_controller phandle for dp phy
Tyler Baker [Mon, 12 Jan 2015 15:54:46 +0000 (07:54 -0800)]
reset: sunxi: fix spinlock initialization
Call spin_lock_init() before the spinlocks are used, both in early init
and probe functions preventing a lockdep splat.
I have been observing lockdep complaining [1] during boot on my a80 optimus [2]
when CONFIG_PROVE_LOCKING has been enabled. This patch resolves the splat,
and has been tested on a few other sunxi platforms without issue.
Olof Johansson [Tue, 13 Jan 2015 23:32:43 +0000 (15:32 -0800)]
Merge tag 'renesas-soc-fixes-for-v3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas into fixes
Merge "Renesas ARM Based SoC Fixes for v3.19" from Simon Horman:
Renesas ARM Based SoC Fixes for v3.19
This pull request is based on the last round of SoC updates for v3.19,
Fourth Round of Renesas ARM Based SoC Updates for v3.19, tagged as
renesas-soc3-for-v3.19, merged into your next/soc branch and included in
v3.19-rc1.
- ARM: shmobile: r8a7740: Instantiate GIC from C board code in legacy builds
Set .control_parent for all irqpin instances for sh73a0 SoC when booting
using legacy C.
- ARM: shmobile: r8a7740: Instantiate GIC from C board code in legacy builds
This fixes a long standing problem which has been present since
the sh73a0 SoC started using the INTC External IRQ pin driver.
The patch that introduced the problem is 341eb5465f67437a ("ARM:
shmobile: INTC External IRQ pin driver on sh73a0") which was included
in v3.10.
* tag 'renesas-soc-fixes-for-v3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
ARM: shmobile: sh73a0 legacy: Set .control_parent for all irqpin instances
ARM: shmobile: r8a7740: Instantiate GIC from C board code in legacy builds
Abhilash Kesavan [Sat, 10 Jan 2015 03:11:36 +0000 (08:41 +0530)]
ARM: dts: disable CCI on exynos5420 based arndale-octa
The arndale-octa board was giving "imprecise external aborts" during
boot-up with MCPM enabled. CCI enablement of the boot cluster was found
to be the cause of these aborts (possibly because the secure f/w was not
allowing it). Hence, disable CCI for the arndale-octa board.
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com> Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Tested-by: Kevin Hilman <khilman@linaro.org> Tested-by: Tyler Baker <tyler.baker@linaro.org> Signed-off-by: Olof Johansson <olof@lixom.net>
Abhilash Kesavan [Sat, 10 Jan 2015 03:11:35 +0000 (08:41 +0530)]
drivers: bus: check cci device tree node status
The arm-cci driver completes the probe sequence even if the cci node is
marked as disabled. Add a check in the driver to honour the cci status
in the device tree.
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Olof Johansson <olof@lixom.net>
Heiko Stübner [Sun, 11 Jan 2015 22:09:23 +0000 (23:09 +0100)]
ARM: rockchip: disable jtag/sdmmc autoswitching on rk3288
rk3288 SoCs have a function to automatically switch between jtag/sdmmc pinmux
settings depending on the card state. This collides with a lot of assumptions.
It only works when using the internal card-detect mechanism and breaks
horribly when using either the normal card-detect via the slot-gpio function
or via any other pin. Also there is of course no link between the mmc and jtag
on the software-side, so the jtag clocks may very well be disabled when the
card is ejected and the soc switches back to the jtag pinmux.
Leaving the switching function enabled did result in mmc timeouts and rcu
stalls thus hanging the system on 3.19-rc1. Therefore disable it in all cases,
as we expect the devicetree to explicitly select either mmc or jtag pinmuxes
anyway.
Signed-off-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Olof Johansson <olof@lixom.net>
Olof Johansson [Sun, 11 Jan 2015 21:07:05 +0000 (13:07 -0800)]
Merge tag 'berlin-fixes-for-3.19-1' of git://git.infradead.org/users/hesselba/linux-berlin into fixes
Merge "ARM: berlin: Fixes for v3.19 (round 1)" from Sebastian Hesselbarth:
Marvell Berlin fixes for v3.19 round 1:
- SDHCI DT fixes for BG2Q and BG2Q reference board
- BG2Q SM GPIO DT node relocation
* tag 'berlin-fixes-for-3.19-1' of git://git.infradead.org/users/hesselba/linux-berlin:
ARM: dts: berlin: correct BG2Q's SM GPIO location.
ARM: dts: berlin: add broken-cd and set bus width for eMMC in Marvell DMP DT
ARM: dts: berlin: fix io clk and add missing core clk for BG2Q sdhci2 host
Linus Walleij [Fri, 9 Jan 2015 19:11:20 +0000 (20:11 +0100)]
ARM: nomadik: fix up leftover device tree pins
We altered the device tree bindings for the Nomadik family of
pin controllers to be standard, this file was merged out-of-order
so we missed fixing this. Fix it up.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Olof Johansson <olof@lixom.net>
Olof Johansson [Thu, 8 Jan 2015 22:43:00 +0000 (14:43 -0800)]
Merge tag 'omap-for-v3.19/fixes-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes
Merge "omap fixes against v3.19-rc1" from Tony Lindgren:
Fixes for omaps mostly to deal with dra7 timer issues
and hypervisor mode. The other fixes are minor fixes for
various boards. The summary of the fixes is:
- Fix real-time counter rate typos for some frequencies
- Fix counter frequency drift for am572x
- Fix booting of secondary CPU in HYP mode
- Fix n900 board name for legacy user space
- Fix cpufreq in omap2plus_defconfig after Kconfig change
- Fix dra7 qspi partitions
And also, let's re-enable smc91x on some n900 boards that
we have sitting in a few test boot systems after the boot
loader dependencies got fixed.
* tag 'omap-for-v3.19/fixes-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: dts: Revert disabling of smc91x for n900
ARM: dts: dra7-evm: fix qspi device tree partition size
ARM: omap2plus_defconfig: use CONFIG_CPUFREQ_DT
ARM: OMAP2+: Fix n900 board name for legacy user space
ARM: omap5/dra7xx: Enable booting secondary CPU in HYP mode
ARM: dra7xx: Fix counter frequency drift for AM572x errata i856
ARM: omap5/dra7xx: Fix frequency typos
Olof Johansson [Thu, 8 Jan 2015 22:42:11 +0000 (14:42 -0800)]
Merge tag 'imx-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into fixes
Merge "ARM: imx: fixes for 3.19" from Shawn Guo:
The i.MX fixes for 3.19:
- One fix for incorrect i.MX25 SPI1 clock assignment in device tree,
which causes system hang when accessing SPI1.
- Correct i.MX6SX QSPI parent clock configuration to fix a kernel Oops.
- Fix ULPI PHY reset modelling on imx51-babbage board to remove the
dependency on bootloader for USB3317 ULPI PHY reset.
- Correct video divider setting on i.MX6Q rev T0 1.0 to fix the issue
that HDMI is not working at high resolution on T0 1.0.
- One incremental fix for CODA960 VPU enabling in device tree to
correct interrupt order.
- LS1021A SCFG block works in BE mode, add device tree property
big-endian to make it right.
* tag 'imx-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
ARM: dts: imx51-babbage: Fix ULPI PHY reset modelling
ARM: imx6sx: Set PLL2 as parent of QSPI clocks
ARM: dts: imx25: Fix the SPI1 clocks
ARM: clk-imx6q: fix video divider for rev T0 1.0
ARM: dts: imx6qdl: Fix CODA960 interrupt order
ARM: ls1021a: dtsi: add 'big-endian' property for scfg node
Olof Johansson [Thu, 8 Jan 2015 22:38:36 +0000 (14:38 -0800)]
Merge tag 'v3.19-rockchip-dtsfixes1' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip into fixes
Merge "ARM: rockchip: dts fix for 3.19" from Heiko Stübner:
Increase drive-strength to sdmmc pins on rk3288-evb to fix
an issue with the fixed highspeed card detection.
* tag 'v3.19-rockchip-dtsfixes1' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip:
ARM: dts: rockchip: bump sd card pin drive strength up on rk3288-evb
Louis Langholtz [Fri, 16 Jan 2015 05:04:46 +0000 (22:04 -0700)]
kernel: avoid overflow in cmp_range
Avoid overflow possibility.
[ The overflow is purely theoretical, since this is used for memory
ranges that aren't even close to using the full 64 bits, but this is
the right thing to do regardless. - Linus ]
Signed-off-by: Louis Langholtz <lou_langholtz@me.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Peter Anvin <hpa@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Namhyung Kim [Wed, 14 Jan 2015 11:18:05 +0000 (20:18 +0900)]
perf tools: Fix segfault for symbol annotation on TUI
Currently the symbol structure is allocated with symbol_conf.priv_size
to carry sideband information like annotation, map browser on TUI and
sort-by-name tree node. So retrieving these information from symbol
needs to care about the details of such placement.
However the annotation code just assumes that the symbol is placed after
the struct annotation. But actually there's other info between them.
So accessing those struct will lead to an undefined behavior (usually a
crash) after they write their info to the same location.
To reproduce the problem, please follow the steps below:
1. run perf report (TUI of course) with -v option
2. open map browser (by pressing right arrow key for any entry)
3. search any function (by pressing '/' key and input whatever..)
4. return to the hist browser (by pressing 'q' or left arrow key)
5. open annotation window for the same entry (by pressing 'a' key)
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1421234288-22758-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Wed, 14 Jan 2015 02:36:47 +0000 (10:36 +0800)]
perf test: Fix dwarf unwind using libunwind.
Perf tool fails to unwind user stack if the event raises in a shared
object. This patch improves tests/dwarf-unwind.c to demonstrate the
problem by utilizing commonly used glibc function "bsearch". If perf is
not statically linked, the testcase will try to unwind a mixed call
trace.
By debugging libunwind I found that there is a bug in unwind-libunwind:
it always passes 0 as segbase to libunwind, cause libunwind unable to
locate debug_frame entry fir first level ip address (I add some more
debugging output into libunwind to make things clear):
This patch passes map->start as segbase to dwarf_find_debug_frame(), so
di will be initialized correctly.
In addition, dso and executable are different when setting segbase. This
patch first check whether the elf is executable, and pass segbase only
for shared object.
Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1421203007-75799-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Vineet Gupta [Tue, 13 Jan 2015 13:43:22 +0000 (19:13 +0530)]
perf tools: Avoid build splat for syscall numbers with uclibc
This is due to duplicated unistd inclusion (via uClibc headers + kernel headers)
Also seen on ARM uClibc based tools
------- ARC build ---------->8-------------
CC util/evlist.o
In file included from
~/arc/k.org/arch/arc/include/uapi/asm/unistd.h:25:0,
from util/../perf-sys.h:10,
from util/../perf.h:15,
from util/event.h:7,
from util/event.c:3:
~/arc/k.org/include/uapi/asm-generic/unistd.h:906:0:
warning: "__NR_fcntl64" redefined [enabled by default]
#define __NR_fcntl64 __NR3264_fcntl
^
In file included from
~/arc/gnu/INSTALL_1412-arc-2014.12-rc1/arc-snps-linux-uclibc/sysroot/usr/include/sys/syscall.h:24:0,
from util/../perf-sys.h:6,
----------------->8-------------------
------- ARM build ---------->8-------------
CC FPIC plugin_scsi.o
In file included from util/../perf-sys.h:9:0,
from util/../perf.h:15,
from util/cache.h:7,
from perf.c:12:
~/arc/k.org/arch/arm/include/uapi/asm/unistd.h:28:0:
warning: "__NR_restart_syscall" redefined [enabled by default]
In file included from
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/sys/syscall.h:25:0,
from util/../perf-sys.h:6,
from util/../perf.h:15,
from util/cache.h:7,
from perf.c:12:
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/bits/sysnum.h:17:0:
note: this is the location of the previous definition
----------------->8-------------------
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1421156604-30603-4-git-send-email-vgupta@synopsys.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Vineet Gupta [Tue, 13 Jan 2015 13:43:21 +0000 (19:13 +0530)]
perf tools: Elide strlcpy warning with uclibc
----------------->8------------------
CC bench/sched-pipe.o
In file included from builtin-annotate.c:13:0:
util/cache.h:76:15: warning: redundant redeclaration of 'strlcpy'
[-Wredundant-decls]
extern size_t strlcpy(char *dest, const char *src, size_t size);
^
In file included from util/util.h:55:0,
from builtin.h:4,
from builtin-annotate.c:8:
~/vineetg/arc/gnu/INSTALL_1412-arc-2014.12-rc1/arc-snps-linux-uclibc/sysroot/usr/include/string.h:396:15:
note: previous declaration of 'strlcpy' was here
extern size_t strlcpy(char *__restrict dst, const char *__restrict src,
----------------->8------------------
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1421156604-30603-3-git-send-email-vgupta@synopsys.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
----------->8---------------
CC fs/fs.o
fs/fs.c: In function 'fs__valid_mount':
fs/fs.c:82:24: error: comparison between signed and unsigned integer
expressions [-Werror=sign-compare]
else if (st_fs.f_type != magic)
^
cc1: all warnings being treated as errors
----------->8---------------
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Cody P Schafer <dev@codyps.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com> Link: http://lkml.kernel.org/r/1420888254-17504-2-git-send-email-vgupta@synopsys.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools: Remove bitops/hweight usage of bits in tools/perf
We need to use lib/hweight.c for that, just like we do for lib/rbtree.c,
so tools need to link hweight.o. For now do it directly, but we need to
have a tools/lib/lk.a or .so that collects these goodies...
Reported-by: Jan Beulich <JBeulich@suse.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-a1e91dx3apzqw5kbdt7ut21s@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When thread__init_map_groups() fails, a new thread should be removed
from the rbtree since it's gonna be freed. Also update last match cache
only if the function succeeded.
Reported-by: David Ahern <dsahern@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1420763892-15535-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Mon, 12 Jan 2015 02:20:55 +0000 (10:20 +0800)]
perf tools: Fix building error in x86_64 when dwarf unwind is on
When build with 'make ARCH=x86' and dwarf unwind is on, there is a
compiling error:
CC /home/wn/perf/arch/x86/util/unwind-libdw.o
CC /home/wn/perf/arch/x86/tests/regs_load.o
arch/x86/tests/regs_load.S: Assembler messages:
arch/x86/tests/regs_load.S:65: Error: operand type mismatch for `push'
arch/x86/tests/regs_load.S:72: Error: operand type mismatch for `pop'
make[1]: *** [/home/wn/perf/arch/x86/tests/regs_load.o] Error 1
make[1]: INTERNAL: Exiting with 25 jobserver tokens available; should be 24!
make: *** [all] Error 2
...
Which is caused by incorrectly undefine macro HAVE_ARCH_X86_64_SUPPORT.
'config/Makefile.arch' tests __x86_64__ only when 'ARCH=x86_64'.
However, when building x86_64 kernel, ARCH=x86 is valid and commonly
used. Build systems, such as yocto, uses x86_64 compiler with 'ARCH=x86'
to build x86_64 perf, which causes mismatching.
As __LP64__ is defined for x86_64 as well, we can consolidate the
__x86_64__ check to the __LP64__ check and get rid of the IS_X86_64
IMHO.
(This patch is made by Namhyung Kim when replying my v1 patch:
https://lkml.org/lkml/2015/1/7/17
I modified the code to remove dependency on RAW_ARCH:
https://lkml.org/lkml/2015/1/7/865
Namhyung Kim didn't provide his SOB in his original email. I add
mine only for my modification.)
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1421029255-23039-1-git-send-email-wangnan0@huawei.com
[ Namhyung provided his S-o-B on a followup to this patch thread on lkml ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Sat, 10 Jan 2015 10:33:48 +0000 (19:33 +0900)]
perf probe: Propagate error code when write(2) failed
When it failed to write probe commands to the probe_event file in
debugfs, it needs to propagate the error code properly. Current code
blindly uses the return value of the write(2) so it always uses
-1 (-EPERM) and it might confuse users.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1420886028-15135-4-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linus Torvalds [Fri, 16 Jan 2015 19:18:08 +0000 (08:18 +1300)]
Merge tag 'char-misc-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are three small driver fixes for reported issues for 3.19-rc5.
All of these have been in linux-next for a while with no reported
problems"
* tag 'char-misc-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
mcb: mcb-pci: Only remap the 1st 0x200 bytes of BAR 0
mei: add ABI documentation for fw_status exported through sysfs
mei: clean reset bit before reset
Linus Torvalds [Fri, 16 Jan 2015 19:15:49 +0000 (08:15 +1300)]
Merge tag 'tty-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver fixes from Greg KH:
"Here are some tty and serial driver fixes for 3.19-rc5 that resolve
some reported issues, and add a new device id to the 8250 serial port
driver.
All have been in linux-next with no reported problems"
* tag 'tty-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: samsung: Add the support for Exynos5433 SoC
Revert "tty: Fix pty master poll() after slave closes v2"
tty: Prevent hw state corruption in exclusive mode reopen
tty: Add support for the WCH384 4S multi-IO card
serial: fix parisc boot hang
Linus Torvalds [Fri, 16 Jan 2015 19:02:44 +0000 (08:02 +1300)]
Merge tag 'usb-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here is a bunch of USB fixes for 3.19-rc5.
Most of these are gadget driver fixes, along with the xhci driver fix
that we both reported having problems with, as well as some new device
ids and other tiny fixes.
All have been in linux-next with no problems"
* tag 'usb-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (43 commits)
usb: dwc3: gadget: Stop TRB preparation after limit is reached
usb: dwc3: gadget: Fix TRB preparation during SG
usb: phy: mv-usb: fix usb_phy build errors
usb: serial: handle -ENODEV quietly in generic_submit_read_urb
usb: serial: silence all non-critical read errors
USB: console: fix potential use after free
USB: console: fix uninitialised ldisc semaphore
usb: gadget: udc: atmel: fix possible oops when unloading module
usb: gadget: gadgetfs: fix an oops in ep_write()
usb: phy: Fix deferred probing
OHCI: add a quirk for ULi M5237 blocking on reset
uas: Add US_FL_NO_ATA_1X for 2 more Seagate disk enclosures
uas: Do not blacklist ASM1153 disk enclosures
usb: gadget: udc: avoid dereference before NULL check in ep_queue
usb: host: ehci-tegra: request deferred probe when failing to get phy
uas: disable UAS on Apricorn SATA dongles
uas: Add US_FL_NO_REPORT_OPCODES for JMicron JMS566 with usb-id 0bc2:a013
uas: Add US_FL_NO_ATA_1X for Seagate devices with usb-id 0bc2:a013
xhci: Add broken-streams quirk for Fresco Logic FL1000G xhci controllers
USB: EHCI: adjust error return code
...
Linus Torvalds [Fri, 16 Jan 2015 19:01:21 +0000 (08:01 +1300)]
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
- Wire up compat_sys_execveat for compat (AArch32) tasks
- Revert 421520ba9829, as this breaks our side of the boot protocol
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: partially revert "ARM: 8167/1: extend the reserved memory for initrd to be page aligned"
arm64: compat: wire up compat_sys_execveat
Linus Torvalds [Fri, 16 Jan 2015 18:59:06 +0000 (07:59 +1300)]
Merge tag 'nfs-for-3.19-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Stable fix for a NFSv3/lockd race
- Fixes for several NFSv4.1 client id trunking bugs
- Remove an incorrect test when checking for delegated opens"
* tag 'nfs-for-3.19-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Remove incorrect check in can_open_delegated()
NFS: Ignore transport protocol when detecting server trunking
NFSv4/v4.1: Verify the client owner id during trunking detection
NFSv4: Cache the NFSv4/v4.1 client owner_id in the struct nfs_client
NFSv4.1: Fix client id trunking on Linux
LOCKD: Fix a race when initialising nlmsvc_timeout
Linus Torvalds [Fri, 16 Jan 2015 18:55:52 +0000 (07:55 +1300)]
Merge tag 'trace-fixes-v3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fixes from Steven Rostedt:
"This holds a few fixes to the ftrace infrastructure as well as the
mixture of function graph tracing and kprobes.
When jprobes and function graph tracing is enabled at the same time it
will crash the system:
After the first fork (jprobe_example probes it), the system will
crash.
This is due to the way jprobes copies the stack frame and does not do
a normal function return. This messes up with the function graph
tracing accounting which hijacks the return address from the stack and
replaces it with a hook function. It saves the return addresses in a
separate stack to put back the correct return address when done. But
because the jprobe functions do not do a normal return, their stack
addresses are not put back until the function they probe is called,
which means that the probed function will get the return address of
the jprobe handler instead of its own.
The simple fix here was to disable function graph tracing while the
jprobe handler is being called.
While debugging this I found two minor bugs with the function graph
tracing.
The first was about the function graph tracer sharing its function
hash with the function tracer (they both get filtered by the same
input). The changing of the set_ftrace_filter would not sync the
function recording records after a change if the function tracer was
disabled but the function graph tracer was enabled. This was due to
the update only checking one of the ops instead of the shared ops to
see if they were enabled and should perform the sync. This caused the
ftrace accounting to break and a ftrace_bug() would be triggered,
disabling ftrace until a reboot.
The second was that the check to update records only checked one of
the filter hashes. It needs to test both the "filter" and "notrace"
hashes. The "filter" hash determines what functions to trace where as
the "notrace" hash determines what functions not to trace (trace all
but these). Both hashes need to be passed to the update code to find
out what change is being done during the update. This also broke the
ftrace record accounting and triggered a ftrace_bug().
This patch set also include two more fixes that were reported
separately from the kprobe issue.
One was that init_ftrace_syscalls() was called twice at boot up. This
is not a major bug, but that call performed a rather large kmalloc
(NR_syscalls * sizeof(*syscalls_metadata)). The second call made the
first one a memory leak, and wastes memory.
The other fix is a regression caused by an update in the v3.19 merge
window. The moving to enable events early, moved the enabling before
PID 1 was created. The syscall events require setting the
TIF_SYSCALL_TRACEPOINT for all tasks. But for_each_process_thread()
does not include the swapper task (PID 0), and ended up being a nop.
A suggested fix was to add the init_task() to have its flag set, but I
didn't really want to mess with PID 0 for this minor bug. Instead I
disable and re-enable events again at early_initcall() where it use to
be enabled. This also handles any other event that might have its own
reg function that could break at early boot up"
* tag 'trace-fixes-v3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix enabling of syscall events on the command line
tracing: Remove extra call to init_ftrace_syscalls()
ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracing
ftrace: Check both notrace and filter for old hash
ftrace: Fix updating of filters for shared global_ops filters
Catalin Marinas [Fri, 16 Jan 2015 13:56:38 +0000 (13:56 +0000)]
arm64: partially revert "ARM: 8167/1: extend the reserved memory for initrd to be page aligned"
This patch partially reverts commit 421520ba98290a73b35b7644e877a48f18e06004
(only the arm64 part). There is no guarantee that the boot-loader places other
images like dtb in a different page than initrd start/end, especially when the
kernel is built with 64KB pages. When this happens, such pages must not be
freed. The free_reserved_area() already takes care of rounding up "start" and
rounding down "end" to avoid freeing partially used pages.
Cc: <stable@vger.kernel.org> # 3.17+ Reported-by: Peter Maydell <Peter.Maydell@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
UOPS_RETIRED.ALL is not a PEBS capable event, so it should not be used
to count cycle number.
Actually SLM calls intel_pebs_aliases_core2() which uses INST_RETIRED.ANY_P
to count the number of cycles. It's a PEBS capable event. But inv and
cmask must be set to count cycles.
Considering SLM allows all events as PEBS with no flags, only
INST_RETIRED.ANY_P, inv=1, cmask=16 needs to handled specially.
Signed-off-by: Kan Liang <kan.liang@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/1421084541-31639-1-git-send-email-kan.liang@intel.com Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
Stephane Eranian [Tue, 13 Jan 2015 22:59:53 +0000 (23:59 +0100)]
perf/rapl: Fix sysfs_show() initialization for RAPL PMU
This patch fixes a problem with the initialization of the
sysfs_show() routine for the RAPL PMU.
The current code was wrongly relying on the EVENT_ATTR_STR()
macro which uses the events_sysfs_show() function in the x86
PMU code. That function itself was relying on the x86_pmu data
structure. Yet RAPL and the core PMU (x86_pmu) have nothing to
do with each other. They should therefore not interact with
each other.
The x86_pmu structure is initialized at boot time based on
the host CPU model. When the host CPU is not supported, the
x86_pmu remains uninitialized and some of the callbacks it
contains are NULL.
The false dependency with x86_pmu could potentially cause crashes
in case the x86_pmu is not initialized while the RAPL PMU is. This
may, for instance, be the case in virtualized environments.
This patch fixes the problem by using a private sysfs_show()
routine for exporting the RAPL PMU events.
Linus Torvalds [Fri, 16 Jan 2015 01:55:47 +0000 (14:55 +1300)]
Merge tag 'fbdev-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux
Pull fbdev fixes from Tomi Valkeinen:
- broadsheetfb: fix memory leak
- simplefb: fix build failure on sparc
* tag 'fbdev-fixes-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux:
fbdev/broadsheetfb: fix memory leak
simplefb: Fix build failure on Sparc
Linus Torvalds [Fri, 16 Jan 2015 01:28:01 +0000 (14:28 +1300)]
Merge tag 'powerpc-3.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc fixes from Michael Ellerman:
"A few powerpc fixes"
* tag 'powerpc-3.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
powerpc: Work around gcc bug in current_thread_info()
cxl: Fix issues when unmapping contexts
powernv: Fix OPAL tracepoint code
tracing: Fix enabling of syscall events on the command line
Commit 5f893b2639b2 "tracing: Move enabling tracepoints to just after
rcu_init()" broke the enabling of system call events from the command
line. The reason was that the enabling of command line trace events
was moved before PID 1 started, and the syscall tracepoints require
that all tasks have the TIF_SYSCALL_TRACEPOINT flag set. But the
swapper task (pid 0) is not part of that. Since the swapper task is the
only task that is running at this early in boot, no task gets the
flag set, and the tracepoint never gets reached.
Instead of setting the swapper task flag (there should be no reason to
do that), re-enabled trace events again after the init thread (PID 1)
has been started. It requires disabling all command line events and
re-enabling them, as just enabling them again will not reset the logic
to set the TIF_SYSCALL_TRACEPOINT flag, as the syscall tracepoint will
be fooled into thinking that it was already set, and wont try setting
it again. For this reason, we must first disable it and re-enable it.
projects / linux-beck.git / log