On Fri, 11 Apr 2025 15:26:10 -0400 Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > > Replying to my email as it appears gmail blocked it. Probably due to all > the escape characters my output had. Resending with that cut out. > > Masami, I was sent a message from gmail that it blocked this from you. Hi, I could find it. Let me reply! > > If you want to see the original email: > > https://lore.kernel.org/all/20250411151358.1d4fd8c7@xxxxxxxxxxxxxxxxxx/ > > -- Steve > > On Fri, 11 Apr 2025 15:13:58 -0400 > Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > > > On Fri, 11 Apr 2025 14:31:32 -0400 > > Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > > > > > Hmm, I just tested this, and it fails on my box too (I test on a debian VM). > > > > > > It fails with and without setting it to bash. I'll take a look too. > > > > Hmm, maybe it is a bashism. > > > > The test has this: > > > > # Max arguments limitation > > MAX_ARGS=128 > > EXCEED_ARGS=$((MAX_ARGS + 1)) > > > > check_max_args() { # event_header > > TEST_STRING=$1 > > # Acceptable > > for i in `seq 1 $MAX_ARGS`; do > > TEST_STRING="$TEST_STRING \\$i" > > done > > echo "$TEST_STRING" >> dynamic_events > > echo > dynamic_events > > # Error > > TEST_STRING="$TEST_STRING \\$EXCEED_ARGS" > > ! echo "$TEST_STRING" >> dynamic_events > > return 0 > > } > > > > # Kprobe max args limitation > > if grep -q "kprobe_events" README; then > > check_max_args "p vfs_read" > > fi > > > > So I tried manually executing this in bash: > > > > --------------------------8<-------------------------- > > # TEST_STRING='p vfs_read' > > # for i in `seq 1 128`; do TEST_STRING="$TEST_STRING \\$i" ; done > > # echo $TEST_STRING > > p vfs_read \1 \2 > > [ This is cut out to see if it doesn't trigger gmail blocking it again! ] > > > # echo "$TEST_STRING" >> /sys/kernel/tracing/dynamic_events > > # echo $? > > 0 > > # cat /sys/kernel/tracing/dynamic_events > > p:kprobes/p_vfs_read_0 vfs_read arg1=\1 > > [ This is cut out to see if it doesn't trigger gmail blocking it again! ] > > > -------------------------->8-------------------------- > > > > Doing the same in dash: > > > > --------------------------8<-------------------------- > > # dash > > # TEST_STRING='p vfs_read' > > # for i in `seq 1 128`; do TEST_STRING="$TEST_STRING \\$i" ; done > > # echo $TEST_STRING > > p vfs_read \8 \9 > > [ This is cut out to see if it doesn't trigger gmail blocking it again! ] > > > # echo "$TEST_STRING" >> /sys/kernel/tracing/dynamic_events > > dash: 8: echo: echo: I/O error > > -------------------------->8-------------------------- > > > > Looks like dash will translate those "\#" into the ASCII equivalent, > > whereas bash does not. > > > > This patch seems to fix it: > > > > diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc b/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc > > index 6b94b678741a..ebe2a34cbf92 100644 > > --- a/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc > > +++ b/tools/testing/selftests/ftrace/test.d/dynevent/dynevent_limitations.tc > > @@ -11,7 +11,7 @@ check_max_args() { # event_header > > TEST_STRING=$1 > > # Acceptable > > for i in `seq 1 $MAX_ARGS`; do > > - TEST_STRING="$TEST_STRING \\$i" > > + TEST_STRING="$TEST_STRING \\\\$i" > > done > > echo "$TEST_STRING" >> dynamic_events > > echo > dynamic_events > > > > > > Masami, you just recently added this test (it's dated March 27th 2025), did > > you mean to write in the ASCII characters? Why the backslash? > > > > -- Steve > -- Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
