On Tue, 4 Aug 2026 21:46:35 +0200
Martin Kaiser <[email protected]> wrote:
> The add/remove eprobe test installs an eprobe for the openat syscall and
> runs ls. It checks the filenames that were opened by ls against a
> whitelist and a blacklist.
>
> Commit 206b25c09080 ("tracing: eprobe: read the complete FILTER_PTR_STRING
> pointer") fixed access to some string fields in eprobes. This triggers
> test failures as the blacklist does not allow relative paths for the
> openat parameters.
>
> What makes this test unstable is the fact that the openat calls vary a
> lot between different systems.
>
> Refactor the test to make it more robust. "cd <directory>" will issue a
> chdir syscall with the target directory as parameter. Set an eprobe on
> the sys_enter_chdir event and filter for the exact directory name. Allow
> (fault) as fallback.
>
Looks good to me.
Fixes: 206b25c09080 ("tracing: eprobe: read the complete FILTER_PTR_STRING
pointer")
Since it is already merged to linus tree.
Let me pick it.
> Reported-by: kernel test robot <[email protected]>
> Closes: https://lore.kernel.org/oe-lkp/[email protected]
> Signed-off-by: Martin Kaiser <[email protected]>
Thanks!
> ---
> .../ftrace/test.d/dynevent/add_remove_eprobe.tc | 16 +++++-----------
> 1 file changed, 5 insertions(+), 11 deletions(-)
>
> diff --git
> a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
> b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
> index c300eb020262..e2322693d0c3 100644
> --- a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
> +++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
> @@ -1,16 +1,16 @@
> #!/bin/sh
> # SPDX-License-Identifier: GPL-2.0
> # description: Generic dynamic event - add/remove eprobe events
> -# requires: dynamic_events events/syscalls/sys_enter_openat
> "<attached-group>.<attached-event> [<args>]":README
> +# requires: dynamic_events events/syscalls/sys_enter_chdir
> "<attached-group>.<attached-event> [<args>]":README
>
> echo 0 > events/enable
>
> clear_dynamic_events
>
> SYSTEM="syscalls"
> -EVENT="sys_enter_openat"
> +EVENT="sys_enter_chdir"
> FIELD="filename"
> -EPROBE="eprobe_open"
> +EPROBE="eprobe_chdir"
> OPTIONS="file=+0(\$filename):ustring"
> echo "e:$EPROBE $SYSTEM/$EVENT $OPTIONS" >> dynamic_events
>
> @@ -18,20 +18,14 @@ grep -q "$EPROBE" dynamic_events
> test -d events/eprobes/$EPROBE
>
> echo 1 > events/eprobes/$EPROBE/enable
> -ls
> +cd /sys/kernel/tracing
> echo 0 > events/eprobes/$EPROBE/enable
>
> -content=`grep '^ *ls-' trace | grep 'file='`
> -nocontent=`grep '^ *ls-' trace | grep 'file=' | grep -v -e '"/' -e '"."' -e
> '(fault)' ` || true
> -
> +content=`grep -e 'file="/sys/kernel/tracing"\|(fault)' trace`
> if [ -z "$content" ]; then
> exit_fail
> fi
>
> -if [ ! -z "$nocontent" ]; then
> - exit_fail
> -fi
> -
> echo "-:$EPROBE" >> dynamic_events
>
> ! grep -q "$EPROBE" dynamic_events
> --
> 2.43.7
>
--
Masami Hiramatsu (Google) <[email protected]>
