From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- Documentation/ABI/testing/sysfs-timecard | 293 +++++++++++++++++++++++++++++++ 1 file changed, 293 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-timecard (limited to 'Documentation/ABI/testing/sysfs-timecard') diff --git a/Documentation/ABI/testing/sysfs-timecard b/Documentation/ABI/testing/sysfs-timecard new file mode 100644 index 000000000..3ae41b763 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-timecard @@ -0,0 +1,293 @@ +What: /sys/class/timecard/ +Date: September 2021 +Contact: Jonathan Lemon +Description: This directory contains files and directories + providing a standardized interface to the ancillary + features of the OpenCompute timecard. + +What: /sys/class/timecard/ocpN/ +Date: September 2021 +Contact: Jonathan Lemon +Description: This directory contains the attributes of the Nth timecard + registered. + +What: /sys/class/timecard/ocpN/available_clock_sources +Date: September 2021 +Contact: Jonathan Lemon +Description: (RO) The list of available time sources that the PHC + uses for clock adjustments. + + ==== ================================================= + NONE no adjustments + PPS adjustments come from the PPS1 selector (default) + TOD adjustments from the GNSS/TOD module + IRIG adjustments from external IRIG-B signal + DCF adjustments from external DCF signal + ==== ================================================= + +What: /sys/class/timecard/ocpN/available_sma_inputs +Date: September 2021 +Contact: Jonathan Lemon +Description: (RO) Set of available destinations (sinks) for a SMA + input signal. + + ===== ================================================ + 10Mhz signal is used as the 10Mhz reference clock + PPS1 signal is sent to the PPS1 selector + PPS2 signal is sent to the PPS2 selector + TS1 signal is sent to timestamper 1 + TS2 signal is sent to timestamper 2 + TS3 signal is sent to timestamper 3 + TS4 signal is sent to timestamper 4 + IRIG signal is sent to the IRIG-B module + DCF signal is sent to the DCF module + FREQ1 signal is sent to frequency counter 1 + FREQ2 signal is sent to frequency counter 2 + FREQ3 signal is sent to frequency counter 3 + FREQ4 signal is sent to frequency counter 4 + None signal input is disabled + ===== ================================================ + +What: /sys/class/timecard/ocpN/available_sma_outputs +Date: May 2021 +Contact: Jonathan Lemon +Description: (RO) Set of available sources for a SMA output signal. + + ===== ================================================ + 10Mhz output is from the 10Mhz reference clock + PHC output PPS is from the PHC clock + MAC output PPS is from the Miniature Atomic Clock + GNSS1 output PPS is from the first GNSS module + GNSS2 output PPS is from the second GNSS module + IRIG output is from the PHC, in IRIG-B format + DCF output is from the PHC, in DCF format + GEN1 output is from frequency generator 1 + GEN2 output is from frequency generator 2 + GEN3 output is from frequency generator 3 + GEN4 output is from frequency generator 4 + GND output is GND + VCC output is VCC + ===== ================================================ + +What: /sys/class/timecard/ocpN/clock_source +Date: September 2021 +Contact: Jonathan Lemon +Description: (RW) Contains the current synchronization source used by + the PHC. May be changed by writing one of the listed + values from the available_clock_sources attribute set. + +What: /sys/class/timecard/ocpN/clock_status_drift +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Contains the current drift value used by the firmware + for internal disciplining of the atomic clock. + +What: /sys/class/timecard/ocpN/clock_status_offset +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Contains the current offset value used by the firmware + for internal disciplining of the atomic clock. + +What: /sys/class/timecard/ocpN/freqX +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Optional directory containing the sysfs nodes for + frequency counter . + +What: /sys/class/timecard/ocpN/freqX/frequency +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Contains the measured frequency over the specified + measurement period. + +What: /sys/class/timecard/ocpN/freqX/seconds +Date: March 2022 +Contact: Jonathan Lemon +Description: (RW) Specifies the number of seconds from 0-255 that the + frequency should be measured over. Write 0 to disable. + +What: /sys/class/timecard/ocpN/genX +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Optional directory containing the sysfs nodes for + frequency generator . + +What: /sys/class/timecard/ocpN/genX/duty +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Specifies the signal duty cycle as a percentage from 1-99. + +What: /sys/class/timecard/ocpN/genX/period +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Specifies the signal period in nanoseconds. + +What: /sys/class/timecard/ocpN/genX/phase +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Specifies the signal phase offset in nanoseconds. + +What: /sys/class/timecard/ocpN/genX/polarity +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Specifies the signal polarity, either 1 or 0. + +What: /sys/class/timecard/ocpN/genX/running +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Either 0 or 1, showing if the signal generator is running. + +What: /sys/class/timecard/ocpN/genX/start +Date: March 2022 +Contact: Jonathan Lemon +Description: (RO) Shows the time in . that the signal generator + started running. + +What: /sys/class/timecard/ocpN/genX/signal +Date: March 2022 +Contact: Jonathan Lemon +Description: (RW) Used to start the signal generator, and summarize + the current status. + + The signal generator may be started by writing the signal + period, followed by the optional signal values. If the + optional values are not provided, they default to the current + settings, which may be obtained from the other sysfs nodes. + + period [duty [phase [polarity]]] + + echo 500000000 > signal # 1/2 second period + echo 1000000 40 100 > signal + echo 0 > signal # turn off generator + + Period and phase are specified in nanoseconds. Duty cycle is + a percentage from 1-99. Polarity is 1 or 0. + + Reading this node will return: + + period duty phase polarity start_time + +What: /sys/class/timecard/ocpN/gnss_sync +Date: September 2021 +Contact: Jonathan Lemon +Description: (RO) Indicates whether a valid GNSS signal is received, + or when the signal was lost. + +What: /sys/class/timecard/ocpN/i2c +Date: September 2021 +Contact: Jonathan Lemon +Description: This optional attribute links to the associated i2c device. + +What: /sys/class/timecard/ocpN/irig_b_mode +Date: September 2021 +Contact: Jonathan Lemon +Description: (RW) An integer from 0-7 indicating the timecode format + of the IRIG-B output signal: B00 + +What: /sys/class/timecard/ocpN/pps +Date: September 2021 +Contact: Jonathan Lemon +Description: This optional attribute links to the associated PPS device. + +What: /sys/class/timecard/ocpN/ptp +Date: September 2021 +Contact: Jonathan Lemon +Description: This attribute links to the associated PTP device. + +What: /sys/class/timecard/ocpN/serialnum +Date: September 2021 +Contact: Jonathan Lemon +Description: (RO) Provides the serial number of the timecard. + +What: /sys/class/timecard/ocpN/sma1 +What: /sys/class/timecard/ocpN/sma2 +What: /sys/class/timecard/ocpN/sma3 +What: /sys/class/timecard/ocpN/sma4 +Date: September 2021 +Contact: Jonathan Lemon +Description: (RW) These attributes specify the direction of the signal + on the associated SMA connectors, and also the signal sink + or source. + + The display format of the attribute is a space separated + list of signals, prefixed by the input/output direction. + + The signal direction may be changed (if supported) by + prefixing the signal list with either "in:" or "out:". + If neither prefix is present, then the direction is unchanged. + + The output signal may be changed by writing one of the listed + values from the available_sma_outputs attribute set. + + The input destinations may be changed by writing multiple + values from the available_sma_inputs attribute set, + separated by spaces. If there are duplicated input + destinations between connectors, the lowest numbered SMA + connector is given priority. + + Note that not all input combinations may make sense. + + The 10Mhz reference clock input is currently only valid + on SMA1 and may not be combined with other destination sinks. + +What: /sys/class/timecard/ocpN/tod_correction +Date: March 2022 +Contact: Jonathan Lemon +Description: (RW) The incoming GNSS signal is in UTC time, and the NMEA + format messages do not provide a TAI offset. This sets the + correction value for the incoming time. + + If UBX_LS is enabled, this should be 0, and the offset is + taken from the UBX-NAV-TIMELS message. + +What: /sys/class/timecard/ocpN/ts_window_adjust +Date: September 2021 +Contact: Jonathan Lemon +Description: (RW) When retrieving the PHC with the PTP SYS_OFFSET_EXTENDED + ioctl, a system timestamp is made before and after the PHC + time is retrieved. The midpoint between the two system + timestamps is usually taken to be the SYS time associated + with the PHC time. This estimate may be wrong, as it depends + on PCI latencies, and when the PHC time was latched + + The attribute value reduces the end timestamp by the given + number of nanoseconds, so the computed midpoint matches the + retrieved PHC time. + + The initial value is set based on measured PCI latency and + the estimated point where the FPGA latches the PHC time. This + value may be changed by writing an unsigned integer. + +What: /sys/class/timecard/ocpN/tty +Date: August 2024 +Contact: Vadim Fedorenko +Description: (RO) Directory containing the sysfs nodes for TTY attributes + +What: /sys/class/timecard/ocpN/tty/ttyGNSS +What: /sys/class/timecard/ocpN/tty/ttyGNSS2 +Date: August 2024 +Contact: Jonathan Lemon +Description: (RO) These optional attributes contain names of the TTY serial + ports associated with the GNSS devices. + +What: /sys/class/timecard/ocpN/tty/ttyMAC +Date: August 2024 +Contact: Jonathan Lemon +Description: (RO) This optional attribute contains name of the TTY serial + port associated with the Miniature Atomic Clock. + +What: /sys/class/timecard/ocpN/tty/ttyNMEA +Date: August 2024 +Contact: Jonathan Lemon +Description: (RO) This optional attribute contains name of the TTY serial + port which outputs the PHC time in NMEA ZDA format. + +What: /sys/class/timecard/ocpN/utc_tai_offset +Date: September 2021 +Contact: Jonathan Lemon +Description: (RW) The DCF and IRIG output signals are in UTC, while the + TimeCard operates on TAI. This attribute allows setting the + offset in seconds, which is added to the TAI timebase for + these formats. + + The offset may be changed by writing an unsigned integer. -- cgit v1.3.1