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-class-rc | 137 +++++++++++++++++++++++++++++++ 1 file changed, 137 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-rc (limited to 'Documentation/ABI/testing/sysfs-class-rc') diff --git a/Documentation/ABI/testing/sysfs-class-rc b/Documentation/ABI/testing/sysfs-class-rc new file mode 100644 index 000000000..84e46d70d --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-rc @@ -0,0 +1,137 @@ +What: /sys/class/rc/ +Date: Apr 2010 +KernelVersion: 2.6.35 +Contact: Mauro Carvalho Chehab +Description: + The rc/ class sub-directory belongs to the Remote Controller + core and provides a sysfs interface for configuring infrared + remote controller receivers. + +What: /sys/class/rc/rc/ +Date: Apr 2010 +KernelVersion: 2.6.35 +Contact: Mauro Carvalho Chehab +Description: + A /sys/class/rc/rcN directory is created for each remote + control receiver device where N is the number of the receiver. + +What: /sys/class/rc/rc/protocols +Date: Jun 2010 +KernelVersion: 2.6.36 +Contact: Mauro Carvalho Chehab +Description: + Reading this file returns a list of available protocols, + something like:: + + "rc5 [rc6] nec jvc [sony]" + + Enabled protocols are shown in [] brackets. + + Writing "+proto" will add a protocol to the list of enabled + protocols. + + Writing "-proto" will remove a protocol from the list of enabled + protocols. + + Writing "proto" will enable only "proto". + + Writing "none" will disable all protocols. + + Write fails with EINVAL if an invalid protocol combination or + unknown protocol name is used. + +What: /sys/class/rc/rc/filter +Date: Jan 2014 +KernelVersion: 3.15 +Contact: Mauro Carvalho Chehab +Description: + Sets the scancode filter expected value. + + Use in combination with /sys/class/rc/rcN/filter_mask to set the + expected value of the bits set in the filter mask. + If the hardware supports it then scancodes which do not match + the filter will be ignored. Otherwise the write will fail with + an error. + + This value may be reset to 0 if the current protocol is altered. + +What: /sys/class/rc/rc/filter_mask +Date: Jan 2014 +KernelVersion: 3.15 +Contact: Mauro Carvalho Chehab +Description: + Sets the scancode filter mask of bits to compare. + Use in combination with /sys/class/rc/rcN/filter to set the bits + of the scancode which should be compared against the expected + value. A value of 0 disables the filter to allow all valid + scancodes to be processed. + + If the hardware supports it then scancodes which do not match + the filter will be ignored. Otherwise the write will fail with + an error. + + This value may be reset to 0 if the current protocol is altered. + +What: /sys/class/rc/rc/wakeup_protocols +Date: Feb 2017 +KernelVersion: 4.11 +Contact: Mauro Carvalho Chehab +Description: + Reading this file returns a list of available protocols to use + for the wakeup filter, something like:: + + "rc-5 nec nec-x rc-6-0 rc-6-6a-24 [rc-6-6a-32] rc-6-mce" + + Note that protocol variants are listed, so "nec", "sony", + "rc-5", "rc-6" have their different bit length encodings + listed if available. + + The enabled wakeup protocol is shown in [] brackets. + + Only one protocol can be selected at a time. + + Writing "proto" will use "proto" for wakeup events. + + Writing "none" will disable wakeup. + + Write fails with EINVAL if an invalid protocol combination or + unknown protocol name is used, or if wakeup is not supported by + the hardware. + +What: /sys/class/rc/rc/wakeup_filter +Date: Jan 2014 +KernelVersion: 3.15 +Contact: Mauro Carvalho Chehab +Description: + Sets the scancode wakeup filter expected value. + + Use in combination with /sys/class/rc/rcN/wakeup_filter_mask to + set the expected value of the bits set in the wakeup filter mask + to trigger a system wake event. + + If the hardware supports it and wakeup_filter_mask is not 0 then + scancodes which match the filter will wake the system from e.g. + suspend to RAM or power off. + + Otherwise the write will fail with an error. + + This value may be reset to 0 if the wakeup protocol is altered. + +What: /sys/class/rc/rc/wakeup_filter_mask +Date: Jan 2014 +KernelVersion: 3.15 +Contact: Mauro Carvalho Chehab +Description: + Sets the scancode wakeup filter mask of bits to compare. + + Use in combination with /sys/class/rc/rcN/wakeup_filter to set + the bits of the scancode which should be compared against the + expected value to trigger a system wake event. + + If the hardware supports it and wakeup_filter_mask is not 0 then + scancodes which match the filter will wake the system from e.g. + suspend to RAM or power off. + + Otherwise the write will fail with an error. + + This value may be reset to 0 if the wakeup protocol is altered. -- cgit v1.3.1