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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /tools/testing/selftests/ftrace/test.d/kprobe
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/ftrace/test.d/kprobe')
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/add_and_remove.tc13
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/busy_check.tc15
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args.tc18
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc48
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_syntax.tc107
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_type.tc38
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kprobe_eventname.tc37
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc56
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kprobe_module.tc29
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_args.tc17
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_maxactive.tc41
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc39
-rw-r--r--tools/testing/selftests/ftrace/test.d/kprobe/probepoint.tc43
13 files changed, 501 insertions, 0 deletions
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/add_and_remove.tc b/tools/testing/selftests/ftrace/test.d/kprobe/add_and_remove.tc
new file mode 100644
index 000000000..4604d2103
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/add_and_remove.tc
@@ -0,0 +1,13 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe dynamic event - adding and removing
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+echo 0 > events/enable
+echo > kprobe_events
+echo p:myevent _do_fork > kprobe_events
+grep myevent kprobe_events
+test -d events/kprobes/myevent
+echo > kprobe_events
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/busy_check.tc b/tools/testing/selftests/ftrace/test.d/kprobe/busy_check.tc
new file mode 100644
index 000000000..bbc443a91
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/busy_check.tc
@@ -0,0 +1,15 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe dynamic event - busy event check
+
+[ -f kprobe_events ] || exit_unsupported
+
+echo 0 > events/enable
+echo > kprobe_events
+echo p:myevent _do_fork > kprobe_events
+test -d events/kprobes/myevent
+echo 1 > events/kprobes/myevent/enable
+echo > kprobe_events && exit_fail # this must fail
+echo 0 > events/kprobes/myevent/enable
+echo > kprobe_events # this must succeed
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args.tc
new file mode 100644
index 000000000..8b43c6804
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args.tc
@@ -0,0 +1,18 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe dynamic event with arguments
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+echo 0 > events/enable
+echo > kprobe_events
+echo 'p:testprobe _do_fork $stack $stack0 +0($stack)' > kprobe_events
+grep testprobe kprobe_events
+test -d events/kprobes/testprobe
+echo 1 > events/kprobes/testprobe/enable
+( echo "forked")
+echo 0 > events/kprobes/testprobe/enable
+echo "-:testprobe" >> kprobe_events
+clear_trace
+test -d events/kprobes/testprobe && exit_fail || exit_pass
+
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc
new file mode 100644
index 000000000..1ad70cdaf
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc
@@ -0,0 +1,48 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe event string type argument
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+echo 0 > events/enable
+echo > kprobe_events
+
+case `uname -m` in
+x86_64)
+ ARG1=%di
+;;
+i[3456]86)
+ ARG1=%ax
+;;
+aarch64)
+ ARG1=%x0
+;;
+arm*)
+ ARG1=%r0
+;;
+ppc64*)
+ ARG1=%r3
+;;
+ppc*)
+ ARG1=%r3
+;;
+*)
+ echo "Please implement other architecture here"
+ exit_untested
+esac
+
+: "Test get argument (1)"
+echo "p:testprobe tracefs_create_dir arg1=+0(${ARG1}):string" > kprobe_events
+echo 1 > events/kprobes/testprobe/enable
+echo "p:test _do_fork" >> kprobe_events
+grep -qe "testprobe.* arg1=\"test\"" trace
+
+echo 0 > events/kprobes/testprobe/enable
+: "Test get argument (2)"
+echo "p:testprobe tracefs_create_dir arg1=+0(${ARG1}):string arg2=+0(${ARG1}):string" > kprobe_events
+echo 1 > events/kprobes/testprobe/enable
+echo "p:test _do_fork" >> kprobe_events
+grep -qe "testprobe.* arg1=\"test\" arg2=\"test\"" trace
+
+echo 0 > events/enable
+echo > kprobe_events
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_syntax.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_syntax.tc
new file mode 100644
index 000000000..92ffb3bd3
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_syntax.tc
@@ -0,0 +1,107 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe event argument syntax
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+grep "x8/16/32/64" README > /dev/null || exit_unsupported # version issue
+
+echo 0 > events/enable
+echo > kprobe_events
+
+PROBEFUNC="vfs_read"
+GOODREG=
+BADREG=
+GOODSYM="_sdata"
+if ! grep -qw ${GOODSYM} /proc/kallsyms ; then
+ GOODSYM=$PROBEFUNC
+fi
+BADSYM="deaqswdefr"
+SYMADDR=0x`grep -w ${GOODSYM} /proc/kallsyms | cut -f 1 -d " "`
+GOODTYPE="x16"
+BADTYPE="y16"
+
+case `uname -m` in
+x86_64|i[3456]86)
+ GOODREG=%ax
+ BADREG=%ex
+;;
+aarch64)
+ GOODREG=%x0
+ BADREG=%ax
+;;
+arm*)
+ GOODREG=%r0
+ BADREG=%ax
+;;
+ppc*)
+ GOODREG=%r3
+ BADREG=%msr
+;;
+*)
+ echo "Please implement other architecture here"
+ exit_untested
+esac
+
+test_goodarg() # Good-args
+{
+ while [ "$1" ]; do
+ echo "p ${PROBEFUNC} $1" > kprobe_events
+ shift 1
+ done;
+}
+
+test_badarg() # Bad-args
+{
+ while [ "$1" ]; do
+ ! echo "p ${PROBEFUNC} $1" > kprobe_events
+ shift 1
+ done;
+}
+
+echo > kprobe_events
+
+: "Register access"
+test_goodarg ${GOODREG}
+test_badarg ${BADREG}
+
+: "Symbol access"
+test_goodarg "@${GOODSYM}" "@${SYMADDR}" "@${GOODSYM}+10" "@${GOODSYM}-10"
+test_badarg "@" "@${BADSYM}" "@${GOODSYM}*10" "@${GOODSYM}/10" \
+ "@${GOODSYM}%10" "@${GOODSYM}&10" "@${GOODSYM}|10"
+
+: "Stack access"
+test_goodarg "\$stack" "\$stack0" "\$stack1"
+test_badarg "\$stackp" "\$stack0+10" "\$stack1-10"
+
+: "Retval access"
+echo "r ${PROBEFUNC} \$retval" > kprobe_events
+! echo "p ${PROBEFUNC} \$retval" > kprobe_events
+
+# $comm was introduced in 4.8, older kernels reject it.
+if grep -A1 "fetcharg:" README | grep -q '\$comm' ; then
+: "Comm access"
+test_goodarg "\$comm"
+fi
+
+: "Indirect memory access"
+test_goodarg "+0(${GOODREG})" "-0(${GOODREG})" "+10(\$stack)" \
+ "+0(\$stack1)" "+10(@${GOODSYM}-10)" "+0(+10(+20(\$stack)))"
+test_badarg "+(${GOODREG})" "(${GOODREG}+10)" "-(${GOODREG})" "(${GOODREG})" \
+ "+10(\$comm)" "+0(${GOODREG})+10"
+
+: "Name assignment"
+test_goodarg "varname=${GOODREG}"
+test_badarg "varname=varname2=${GOODREG}"
+
+: "Type syntax"
+test_goodarg "${GOODREG}:${GOODTYPE}"
+test_badarg "${GOODREG}::${GOODTYPE}" "${GOODREG}:${BADTYPE}" \
+ "${GOODTYPE}:${GOODREG}"
+
+: "Combination check"
+
+test_goodarg "\$comm:string" "+0(\$stack):string"
+test_badarg "\$comm:x64" "\$stack:string" "${GOODREG}:string"
+
+echo > kprobe_events
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_type.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_type.tc
new file mode 100644
index 000000000..2a1755bfc
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_type.tc
@@ -0,0 +1,38 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobes event arguments with types
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+grep "x8/16/32/64" README > /dev/null || exit_unsupported # version issue
+
+echo 0 > events/enable
+echo > kprobe_events
+enable_tracing
+
+echo 'p:testprobe _do_fork $stack0:s32 $stack0:u32 $stack0:x32 $stack0:b8@4/32' > kprobe_events
+grep testprobe kprobe_events
+test -d events/kprobes/testprobe
+
+echo 1 > events/kprobes/testprobe/enable
+( echo "forked")
+echo 0 > events/kprobes/testprobe/enable
+ARGS=`tail -n 1 trace | sed -e 's/.* arg1=\(.*\) arg2=\(.*\) arg3=\(.*\) arg4=\(.*\)/\1 \2 \3 \4/'`
+
+check_types() {
+ X1=`printf "%x" $1 | tail -c 8`
+ X2=`printf "%x" $2`
+ X3=`printf "%x" $3`
+ test $X1 = $X2
+ test $X2 = $X3
+ test 0x$X3 = $3
+
+ B4=`printf "%02x" $4`
+ B3=`echo -n $X3 | tail -c 3 | head -c 2`
+ test $B3 = $B4
+}
+check_types $ARGS
+
+echo "-:testprobe" >> kprobe_events
+clear_trace
+test -d events/kprobes/testprobe && exit_fail || exit_pass
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_eventname.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_eventname.tc
new file mode 100644
index 000000000..2724a1068
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_eventname.tc
@@ -0,0 +1,37 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe event auto/manual naming
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+disable_events
+echo > kprobe_events
+
+:;: "Add an event on function without name" ;:
+
+FUNC=`grep " [tT] .*vfs_read$" /proc/kallsyms | tail -n 1 | cut -f 3 -d " "`
+[ "x" != "x$FUNC" ] || exit_unresolved
+echo "p $FUNC" > kprobe_events
+PROBE_NAME=`echo $FUNC | tr ".:" "_"`
+test -d events/kprobes/p_${PROBE_NAME}_0 || exit_failure
+
+:;: "Add an event on function with new name" ;:
+
+echo "p:event1 $FUNC" > kprobe_events
+test -d events/kprobes/event1 || exit_failure
+
+:;: "Add an event on function with new name and group" ;:
+
+echo "p:kprobes2/event2 $FUNC" > kprobe_events
+test -d events/kprobes2/event2 || exit_failure
+
+:;: "Add an event on dot function without name" ;:
+
+FUNC=`grep -m 10 " [tT] .*\.isra\..*$" /proc/kallsyms | tail -n 1 | cut -f 3 -d " "`
+[ "x" != "x$FUNC" ] || exit_unresolved
+echo "p $FUNC" > kprobe_events
+EVENT=`grep $FUNC kprobe_events | cut -f 1 -d " " | cut -f 2 -d:`
+[ "x" != "x$EVENT" ] || exit_failure
+test -d events/$EVENT || exit_failure
+
+echo > kprobe_events
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc
new file mode 100644
index 000000000..cc4cac0e6
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_ftrace.tc
@@ -0,0 +1,56 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe dynamic event with function tracer
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+grep function available_tracers || exit_unsupported # this is configurable
+
+# prepare
+echo nop > current_tracer
+echo _do_fork > set_ftrace_filter
+echo 0 > events/enable
+echo > kprobe_events
+echo 'p:testprobe _do_fork' > kprobe_events
+
+# kprobe on / ftrace off
+echo 1 > events/kprobes/testprobe/enable
+echo > trace
+( echo "forked")
+grep testprobe trace
+! grep '_do_fork <-' trace
+
+# kprobe on / ftrace on
+echo function > current_tracer
+echo > trace
+( echo "forked")
+grep testprobe trace
+grep '_do_fork <-' trace
+
+# kprobe off / ftrace on
+echo 0 > events/kprobes/testprobe/enable
+echo > trace
+( echo "forked")
+! grep testprobe trace
+grep '_do_fork <-' trace
+
+# kprobe on / ftrace on
+echo 1 > events/kprobes/testprobe/enable
+echo function > current_tracer
+echo > trace
+( echo "forked")
+grep testprobe trace
+grep '_do_fork <-' trace
+
+# kprobe on / ftrace off
+echo nop > current_tracer
+echo > trace
+( echo "forked")
+grep testprobe trace
+! grep '_do_fork <-' trace
+
+# cleanup
+echo nop > current_tracer
+echo > set_ftrace_filter
+echo 0 > events/kprobes/testprobe/enable
+echo > kprobe_events
+echo > trace
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_module.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_module.tc
new file mode 100644
index 000000000..1e9f75f7a
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_module.tc
@@ -0,0 +1,29 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe dynamic event - probing module
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+disable_events
+echo > kprobe_events
+
+:;: "Add an event on a module function without specifying event name" ;:
+
+MOD=`lsmod | head -n 2 | tail -n 1 | cut -f1 -d" "`
+FUNC=`grep -m 1 ".* t .*\\[$MOD\\]" /proc/kallsyms | xargs | cut -f3 -d" "`
+[ "x" != "x$MOD" -a "y" != "y$FUNC" ] || exit_unresolved
+echo "p $MOD:$FUNC" > kprobe_events
+PROBE_NAME=`echo $MOD:$FUNC | tr ".:" "_"`
+test -d events/kprobes/p_${PROBE_NAME}_0 || exit_failure
+
+:;: "Add an event on a module function with new event name" ;:
+
+echo "p:event1 $MOD:$FUNC" > kprobe_events
+test -d events/kprobes/event1 || exit_failure
+
+:;: "Add an event on a module function with new event and group name" ;:
+
+echo "p:kprobes1/event1 $MOD:$FUNC" > kprobe_events
+test -d events/kprobes1/event1 || exit_failure
+
+echo > kprobe_events
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_args.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_args.tc
new file mode 100644
index 000000000..321954683
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_args.tc
@@ -0,0 +1,17 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kretprobe dynamic event with arguments
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+echo 0 > events/enable
+echo > kprobe_events
+echo 'r:testprobe2 _do_fork $retval' > kprobe_events
+grep testprobe2 kprobe_events
+test -d events/kprobes/testprobe2
+echo 1 > events/kprobes/testprobe2/enable
+( echo "forked")
+echo 0 > events/kprobes/testprobe2/enable
+echo '-:testprobe2' >> kprobe_events
+clear_trace
+test -d events/kprobes/testprobe2 && exit_fail || exit_pass
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_maxactive.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_maxactive.tc
new file mode 100644
index 000000000..7c0290684
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_maxactive.tc
@@ -0,0 +1,41 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kretprobe dynamic event with maxactive
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+grep -q 'r\[maxactive\]' README || exit_unsupported # this is older version
+
+echo > kprobe_events
+
+# Test if we successfully reject unknown messages
+if echo 'a:myprobeaccept inet_csk_accept' > kprobe_events; then false; else true; fi
+
+# Test if we successfully reject too big maxactive
+if echo 'r1000000:myprobeaccept inet_csk_accept' > kprobe_events; then false; else true; fi
+
+# Test if we successfully reject unparsable numbers for maxactive
+if echo 'r10fuzz:myprobeaccept inet_csk_accept' > kprobe_events; then false; else true; fi
+
+# Test for kretprobe with event name without maxactive
+echo 'r:myprobeaccept inet_csk_accept' > kprobe_events
+grep myprobeaccept kprobe_events
+test -d events/kprobes/myprobeaccept
+echo '-:myprobeaccept' >> kprobe_events
+
+# Test for kretprobe with event name with a small maxactive
+echo 'r10:myprobeaccept inet_csk_accept' > kprobe_events
+grep myprobeaccept kprobe_events
+test -d events/kprobes/myprobeaccept
+echo '-:myprobeaccept' >> kprobe_events
+
+# Test for kretprobe without event name without maxactive
+echo 'r inet_csk_accept' > kprobe_events
+grep inet_csk_accept kprobe_events
+echo > kprobe_events
+
+# Test for kretprobe without event name with a small maxactive
+echo 'r10 inet_csk_accept' > kprobe_events
+grep inet_csk_accept kprobe_events
+echo > kprobe_events
+
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
new file mode 100644
index 000000000..da298f191
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
@@ -0,0 +1,39 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Register/unregister many kprobe events
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+# ftrace fentry skip size depends on the machine architecture.
+# Currently HAVE_KPROBES_ON_FTRACE defined on x86 and powerpc64le
+case `uname -m` in
+ x86_64|i[3456]86) OFFS=5;;
+ ppc64le) OFFS=8;;
+ *) OFFS=0;;
+esac
+
+if [ -d events/kprobes ]; then
+ echo 0 > events/kprobes/enable
+ echo > kprobe_events
+fi
+
+N=0
+echo "Setup up kprobes on first available 256 text symbols"
+grep -i " t " /proc/kallsyms | cut -f3 -d" " | grep -v .*\\..* | \
+while read i; do
+ echo p ${i}+${OFFS} >> kprobe_events && N=$((N+1)) ||:
+ test $N -eq 256 && break
+done
+
+L=`cat kprobe_events | wc -l`
+if [ $L -ne 256 ]; then
+ echo "The number of kprobes events ($L) is not 256"
+ exit_fail
+fi
+
+echo 1 > events/kprobes/enable
+echo 0 > events/kprobes/enable
+echo > kprobe_events
+echo "Waiting for unoptimizing & freeing"
+sleep 5
+echo "Done"
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/probepoint.tc b/tools/testing/selftests/ftrace/test.d/kprobe/probepoint.tc
new file mode 100644
index 000000000..519d2763f
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/probepoint.tc
@@ -0,0 +1,43 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Kprobe events - probe points
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+TARGET_FUNC=tracefs_create_dir
+
+dec_addr() { # hexaddr
+ printf "%d" "0x"`echo $1 | tail -c 8`
+}
+
+set_offs() { # prev target next
+ A1=`dec_addr $1`
+ A2=`dec_addr $2`
+ A3=`dec_addr $3`
+ TARGET="0x$2" # an address
+ PREV=`expr $A1 - $A2` # offset to previous symbol
+ NEXT=+`expr $A3 - $A2` # offset to next symbol
+ OVERFLOW=+`printf "0x%x" ${PREV}` # overflow offset to previous symbol
+}
+
+# We have to decode symbol addresses to get correct offsets.
+# If the offset is not an instruction boundary, it cause -EILSEQ.
+set_offs `grep -A1 -B1 ${TARGET_FUNC} /proc/kallsyms | cut -f 1 -d " " | xargs`
+
+UINT_TEST=no
+# printf "%x" -1 returns (unsigned long)-1.
+if [ `printf "%x" -1 | wc -c` != 9 ]; then
+ UINT_TEST=yes
+fi
+
+echo 0 > events/enable
+echo > kprobe_events
+echo "p:testprobe ${TARGET_FUNC}" > kprobe_events
+echo "p:testprobe ${TARGET}" > kprobe_events
+echo "p:testprobe ${TARGET_FUNC}${NEXT}" > kprobe_events
+! echo "p:testprobe ${TARGET_FUNC}${PREV}" > kprobe_events
+if [ "${UINT_TEST}" = yes ]; then
+! echo "p:testprobe ${TARGET_FUNC}${OVERFLOW}" > kprobe_events
+fi
+echo > kprobe_events
+clear_trace