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 --- tools/scripts/utilities.mak | 199 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 199 insertions(+) create mode 100644 tools/scripts/utilities.mak (limited to 'tools/scripts/utilities.mak') diff --git a/tools/scripts/utilities.mak b/tools/scripts/utilities.mak new file mode 100644 index 000000000..d69d0345c --- /dev/null +++ b/tools/scripts/utilities.mak @@ -0,0 +1,199 @@ +# This allows us to work with the newline character: +define newline + + +endef +newline := $(newline) + +# nl-escape +# +# Usage: escape = $(call nl-escape[,escape]) +# +# This is used as the common way to specify +# what should replace a newline when escaping +# newlines; the default is a bizarre string. +# +nl-escape = $(if $(1),$(1),m822df3020w6a44id34bt574ctac44eb9f4n) + +# escape-nl +# +# Usage: escaped-text = $(call escape-nl,text[,escape]) +# +# GNU make's $(shell ...) function converts to a +# single space each newline character in the output +# produced during the expansion; this may not be +# desirable. +# +# The only solution is to change each newline into +# something that won't be converted, so that the +# information can be recovered later with +# $(call unescape-nl...) +# +escape-nl = $(subst $(newline),$(call nl-escape,$(2)),$(1)) + +# unescape-nl +# +# Usage: text = $(call unescape-nl,escaped-text[,escape]) +# +# See escape-nl. +# +unescape-nl = $(subst $(call nl-escape,$(2)),$(newline),$(1)) + +# shell-escape-nl +# +# Usage: $(shell some-command | $(call shell-escape-nl[,escape])) +# +# Use this to escape newlines from within a shell call; +# the default escape is a bizarre string. +# +# NOTE: The escape is used directly as a string constant +# in an `awk' program that is delimited by shell +# single-quotes, so be wary of the characters +# that are chosen. +# +define shell-escape-nl +awk 'NR==1 {t=$$0} NR>1 {t=t "$(nl-escape)" $$0} END {printf t}' +endef + +# shell-unescape-nl +# +# Usage: $(shell some-command | $(call shell-unescape-nl[,escape])) +# +# Use this to unescape newlines from within a shell call; +# the default escape is a bizarre string. +# +# NOTE: The escape is used directly as an extended regular +# expression constant in an `awk' program that is +# delimited by shell single-quotes, so be wary +# of the characters that are chosen. +# +# (The bash shell has a bug where `{gsub(...),...}' is +# misinterpreted as a brace expansion; this can be +# overcome by putting a space between `{' and `gsub'). +# +define shell-unescape-nl +awk 'NR==1 {t=$$0} NR>1 {t=t "\n" $$0} END { gsub(/$(nl-escape)/,"\n",t); printf t }' +endef + +# escape-for-shell-sq +# +# Usage: embeddable-text = $(call escape-for-shell-sq,text) +# +# This function produces text that is suitable for +# embedding in a shell string that is delimited by +# single-quotes. +# +escape-for-shell-sq = $(subst ','\'',$(1)) + +# shell-sq +# +# Usage: single-quoted-and-escaped-text = $(call shell-sq,text) +# +shell-sq = '$(escape-for-shell-sq)' + +# shell-wordify +# +# Usage: wordified-text = $(call shell-wordify,text) +# +# For instance: +# +# |define text +# |hello +# |world +# |endef +# | +# |target: +# | echo $(call shell-wordify,$(text)) +# +# At least GNU make gets confused by expanding a newline +# within the context of a command line of a makefile rule +# (this is in constrast to a `$(shell ...)' function call, +# which can handle it just fine). +# +# This function avoids the problem by producing a string +# that works as a shell word, regardless of whether or +# not it contains a newline. +# +# If the text to be wordified contains a newline, then +# an intrictate shell command substitution is constructed +# to render the text as a single line; when the shell +# processes the resulting escaped text, it transforms +# it into the original unescaped text. +# +# If the text does not contain a newline, then this function +# produces the same results as the `$(shell-sq)' function. +# +shell-wordify = $(if $(findstring $(newline),$(1)),$(_sw-esc-nl),$(shell-sq)) +define _sw-esc-nl +"$$(echo $(call escape-nl,$(shell-sq),$(2)) | $(call shell-unescape-nl,$(2)))" +endef + +# is-absolute +# +# Usage: bool-value = $(call is-absolute,path) +# +is-absolute = $(shell echo $(shell-sq) | grep -q ^/ && echo y) + +# lookup +# +# Usage: absolute-executable-path-or-empty = $(call lookup,path) +# +# (It's necessary to use `sh -c' because GNU make messes up by +# trying too hard and getting things wrong). +# +lookup = $(call unescape-nl,$(shell sh -c $(_l-sh))) +_l-sh = $(call shell-sq,command -v $(shell-sq) | $(call shell-escape-nl,)) + +# is-executable +# +# Usage: bool-value = $(call is-executable,path) +# +# (It's necessary to use `sh -c' because GNU make messes up by +# trying too hard and getting things wrong). +# +is-executable = $(call _is-executable-helper,$(shell-sq)) +_is-executable-helper = $(shell sh -c $(_is-executable-sh)) +_is-executable-sh = $(call shell-sq,test -f $(1) -a -x $(1) && echo y) + +# get-executable +# +# Usage: absolute-executable-path-or-empty = $(call get-executable,path) +# +# The goal is to get an absolute path for an executable; +# the `command -v' is defined by POSIX, but it's not +# necessarily very portable, so it's only used if +# relative path resolution is requested, as determined +# by the presence of a leading `/'. +# +get-executable = $(if $(1),$(if $(is-absolute),$(_ge-abspath),$(lookup))) +_ge-abspath = $(if $(is-executable),$(1)) + +# get-supplied-or-default-executable +# +# Usage: absolute-executable-path-or-empty = $(call get-executable-or-default,variable,default) +# +define get-executable-or-default +$(if $($(1)),$(call _ge_attempt,$($(1)),$(1)),$(call _ge_attempt,$(2))) +endef +_ge_attempt = $(or $(get-executable),$(call _gea_err,$(2))) +_gea_err = $(if $(1),$(error Please set '$(1)' appropriately)) + +# version-ge3 +# +# Usage $(call version-ge3,2.6.4,$(FLEX_VERSION)) +# +# To compare if a 3 component version is greater or equal to another, first use +# was to check the flex version to see if we can use compiler warnings as +# errors for one of the cases flex generates code C compilers complains about. + +version-ge3 = $(shell echo "$(1).$(2)" | awk -F'.' '{ printf("%d\n", (10000000 * $$1 + 10000 * $$2 + $$3) >= (10000000 * $$4 + 10000 * $$5 + $$6)) }') + +# version-lt3 +# +# Usage $(call version-lt3,2.6.2,$(FLEX_VERSION)) +# +# To compare if a 3 component version is less thjan another, first use was to +# check the flex version to see if we can use compiler warnings as errors for +# one of the cases flex generates code C compilers complains about. + +version-lt3 = $(shell echo "$(1).$(2)" | awk -F'.' '{ printf("%d\n", (10000000 * $$1 + 10000 * $$2 + $$3) < (10000000 * $$4 + 10000 * $$5 + $$6)) }') -- cgit v1.3.1