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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-23 08:07:02 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-23 08:07:02 +0200 |
| commit | 67bfce0e01927859618b76ff5a36a7f23b412cef (patch) | |
| tree | 0608ca6cc9c35059acd10454704346edcfdfbd7e /kernel | |
| parent | 473aec0e1f84be97c7ea52c4266b7ef13ce36af3 (diff) | |
| parent | 6b9b6413700e104934734b72a3be622a76923b98 (diff) | |
| download | lwn-67bfce0e01927859618b76ff5a36a7f23b412cef.tar.gz lwn-67bfce0e01927859618b76ff5a36a7f23b412cef.zip | |
Merge tag 'trace-v5.17-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fix from Steven Rostedt:
"Fix s390 breakage from sorting mcount tables.
The latest merge of the tracing tree sorts the mcount table at build
time. But s390 appears to do things differently (like always) and
replaces the sorted table back to the original unsorted one. As the
ftrace algorithm depends on it being sorted, bad things happen when it
is not, and s390 experienced those bad things.
Add a new config to tell the boot if the mcount table is sorted or
not, and allow s390 to opt out of it"
* tag 'trace-v5.17-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Fix assuming build time sort works for s390
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/Kconfig | 9 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 4 |
2 files changed, 10 insertions, 3 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index f468767bc287..752ed89a293b 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -70,6 +70,13 @@ config HAVE_C_RECORDMCOUNT help C version of recordmcount available? +config BUILDTIME_MCOUNT_SORT + bool + default y + depends on BUILDTIME_TABLE_SORT && !S390 + help + Sort the mcount_loc section at build time. + config TRACER_MAX_TRACE bool @@ -918,7 +925,7 @@ config EVENT_TRACE_TEST_SYSCALLS config FTRACE_SORT_STARTUP_TEST bool "Verify compile time sorting of ftrace functions" depends on DYNAMIC_FTRACE - depends on BUILDTIME_TABLE_SORT + depends on BUILDTIME_MCOUNT_SORT help Sorting of the mcount_loc sections that is used to find the where the ftrace knows where to patch functions for tracing diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 6163b6f762f7..f9feb197b2da 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6435,10 +6435,10 @@ static int ftrace_process_locs(struct module *mod, /* * Sorting mcount in vmlinux at build time depend on - * CONFIG_BUILDTIME_TABLE_SORT, while mcount loc in + * CONFIG_BUILDTIME_MCOUNT_SORT, while mcount loc in * modules can not be sorted at build time. */ - if (!IS_ENABLED(CONFIG_BUILDTIME_TABLE_SORT) || mod) { + if (!IS_ENABLED(CONFIG_BUILDTIME_MCOUNT_SORT) || mod) { sort(start, count, sizeof(*start), ftrace_cmp_ips, NULL); } else { |