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/debugfs-dwc-pcie | 157 +++++++++++++++++++++++++++++ 1 file changed, 157 insertions(+) create mode 100644 Documentation/ABI/testing/debugfs-dwc-pcie (limited to 'Documentation/ABI/testing/debugfs-dwc-pcie') diff --git a/Documentation/ABI/testing/debugfs-dwc-pcie b/Documentation/ABI/testing/debugfs-dwc-pcie new file mode 100644 index 000000000..92b76f52a --- /dev/null +++ b/Documentation/ABI/testing/debugfs-dwc-pcie @@ -0,0 +1,157 @@ +What: /sys/kernel/debug/dwc_pcie_/rasdes_debug/lane_detect +Date: February 2025 +Contact: Shradha Todi +Description: (RW) Write the lane number to be checked for detection. Read + will return whether PHY indicates receiver detection on the + selected lane. The default selected lane is Lane0. + +What: /sys/kernel/debug/dwc_pcie_/rasdes_debug/rx_valid +Date: February 2025 +Contact: Shradha Todi +Description: (RW) Write the lane number to be checked as valid or invalid. + Read will return the status of PIPE RXVALID signal of the + selected lane. The default selected lane is Lane0. + +What: /sys/kernel/debug/dwc_pcie_/rasdes_err_inj/ +Date: February 2025 +Contact: Shradha Todi +Description: The "rasdes_err_inj" is a directory which can be used to inject + errors into the system. The possible errors that can be injected + are: + + 1) tx_lcrc - TLP LCRC error injection TX Path + 2) b16_crc_dllp - 16b CRC error injection of ACK/NAK DLLP + 3) b16_crc_upd_fc - 16b CRC error injection of Update-FC DLLP + 4) tx_ecrc - TLP ECRC error injection TX Path + 5) fcrc_tlp - TLP's FCRC error injection TX Path + 6) parity_tsos - Parity error of TSOS + 7) parity_skpos - Parity error on SKPOS + 8) rx_lcrc - LCRC error injection RX Path + 9) rx_ecrc - ECRC error injection RX Path + 10) tlp_err_seq - TLPs SEQ# error + 11) ack_nak_dllp_seq - DLLPS ACK/NAK SEQ# error + 12) ack_nak_dllp - ACK/NAK DLLPs transmission block + 13) upd_fc_dllp - UpdateFC DLLPs transmission block + 14) nak_dllp - Always transmission for NAK DLLP + 15) inv_sync_hdr_sym - Invert SYNC header + 16) com_pad_ts1 - COM/PAD TS1 order set + 17) com_pad_ts2 - COM/PAD TS2 order set + 18) com_fts - COM/FTS FTS order set + 19) com_idl - COM/IDL E-idle order set + 20) end_edb - END/EDB symbol + 21) stp_sdp - STP/SDP symbol + 22) com_skp - COM/SKP SKP order set + 23) posted_tlp_hdr - Posted TLP Header credit value control + 24) non_post_tlp_hdr - Non-Posted TLP Header credit value control + 25) cmpl_tlp_hdr - Completion TLP Header credit value control + 26) posted_tlp_data - Posted TLP Data credit value control + 27) non_post_tlp_data - Non-Posted TLP Data credit value control + 28) cmpl_tlp_data - Completion TLP Data credit value control + 29) duplicate_tlp - Generates duplicate TLPs + 30) nullified_tlp - Generates Nullified TLPs + + (WO) Write to the attribute will prepare controller to inject + the respective error in the next transmission of data. + + Parameter required to write will change in the following ways: + + - Errors 9 and 10 are sequence errors. The write command: + + echo > /sys/kernel/debug/dwc_pcie_/rasdes_err_inj/ + + + Number of errors to be injected + + The difference to add or subtract from natural + sequence number to generate sequence error. + Allowed range from -4095 to 4095 + + - Errors 23 to 28 are credit value error insertions. The write + command: + + echo > /sys/kernel/debug/dwc_pcie_/rasdes_err_inj/ + + + Number of errors to be injected + + The difference to add or subtract from UpdateFC + credit value. Allowed range from -4095 to 4095 + + Target VC number + + - All other errors. The write command: + + echo > /sys/kernel/debug/dwc_pcie_/rasdes_err_inj/ + + + Number of errors to be injected + +What: /sys/kernel/debug/dwc_pcie_/rasdes_event_counters//counter_enable +Date: February 2025 +Contact: Shradha Todi +Description: The "rasdes_event_counters" is the directory which can be used + to collect statistical data about the number of times a certain + event has occurred in the controller. The list of possible + events are: + + 1) EBUF Overflow + 2) EBUF Underrun + 3) Decode Error + 4) Running Disparity Error + 5) SKP OS Parity Error + 6) SYNC Header Error + 7) Rx Valid De-assertion + 8) CTL SKP OS Parity Error + 9) 1st Retimer Parity Error + 10) 2nd Retimer Parity Error + 11) Margin CRC and Parity Error + 12) Detect EI Infer + 13) Receiver Error + 14) RX Recovery Req + 15) N_FTS Timeout + 16) Framing Error + 17) Deskew Error + 18) Framing Error In L0 + 19) Deskew Uncompleted Error + 20) Bad TLP + 21) LCRC Error + 22) Bad DLLP + 23) Replay Number Rollover + 24) Replay Timeout + 25) Rx Nak DLLP + 26) Tx Nak DLLP + 27) Retry TLP + 28) FC Timeout + 29) Poisoned TLP + 30) ECRC Error + 31) Unsupported Request + 32) Completer Abort + 33) Completion Timeout + 34) EBUF SKP Add + 35) EBUF SKP Del + + (RW) Write 1 to enable the event counter and write 0 to disable + the event counter. Read will return whether the counter is + currently enabled or disabled. Counter is disabled by default. + +What: /sys/kernel/debug/dwc_pcie_/rasdes_event_counters//counter_value +Date: February 2025 +Contact: Shradha Todi +Description: (RO) Read will return the current value of the event counter. + To reset the counter, counter should be disabled first and then + enabled back using the "counter_enable" attribute. + +What: /sys/kernel/debug/dwc_pcie_/rasdes_event_counters//lane_select +Date: February 2025 +Contact: Shradha Todi +Description: (RW) Some lanes in the event list are lane specific events. + These include events from 1 to 11, as well as, 34 and 35. Write + the lane number for which you wish the counter to be enabled, + disabled, or value dumped. Read will return the current + selected lane number. Lane0 is selected by default. + +What: /sys/kernel/debug/dwc_pcie_/ltssm_status +Date: February 2025 +Contact: Hans Zhang <18255117159@163.com> +Description: (RO) Read will return the current PCIe LTSSM state in both + string and raw value. -- cgit v1.3.1