On 06. 01. 2023. 22:18, Mirsad Goran Todorovac wrote:
Hi all,
In the same environment as the previous bug report (Lenovo Ideapad 3 15ITL6 laptop
running Ubuntu 22.10 kinetic kudu and 6.2-rc2 vanilla Torvalds tree kernel), the
next test in the ...selftest/proc/* sequence spuriously fails in assert (i1 <= i0).
Please note that the compiler is the novelty GCC 12.2.0-3ubuntu1.
This was previously hidden by premature hang in the `make kselftest` run due to
proc-empty-vm an proc-pid-vm problems that are now fixed.
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
It happens about half of the times the program is called.
The source seems OK, I can't tell why the idle counter doesn't look monotonic to
the program.
Hope this helps.
BTW, good news: this time I have checked independently, and this is the last test from the .../selftest/proc
group that doesn't have clean exit code 0.
UPDATE:
The same behavior independently occurred with GCC 10.4.0, 9.5.0, 8.5.0 and 6.5.0.
Apparently this happens in 30% to 50% of attempts. Perhaps that's why it wasn't discovered yet:
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# make CC=gcc-10
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread fd-001-lookup.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/fd-001-lookup
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread fd-002-posix-eq.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/fd-002-posix-eq
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread fd-003-kthread.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/fd-003-kthread
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-loadavg-001.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-loadavg-001
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-empty-vm.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-empty-vm
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-pid-vm.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-pid-vm
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-self-map-files-001.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-self-map-files-001
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-self-map-files-002.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-self-map-files-002
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-self-syscall.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-self-syscall
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-self-wchan.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-self-wchan
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-subset-pid.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-subset-pid
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-tid0.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-tid0
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-uptime-001.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-uptime-001
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-uptime-002.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-uptime-002
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread read.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/read
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread self.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/self
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread setns-dcache.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/setns-dcache
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread setns-sysvipc.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/setns-sysvipc
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread thread-self.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/thread-self
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-multiple-procfs.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-multiple-procfs
gcc-10 -Wall -O2 -Wno-unused-function -D_GNU_SOURCE -pthread proc-fsconfig-hidepid.c -o
/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc/proc-fsconfig-hidepid
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# for exe in `ls -l | grep -e -x |
awk '{ print $9 }'`; do echo -n ${exe}':'; ./$exe ; echo "exit=$?" ; done
fd-001-lookup:exit=0
fd-002-posix-eq:exit=0
fd-003-kthread:exit=0
proc-empty-vm:exit=0
proc-fsconfig-hidepid:exit=0
proc-loadavg-001:exit=0
proc-multiple-procfs:exit=0
proc-pid-vm:exit=0
proc-self-map-files-001:exit=0
proc-self-map-files-002:exit=0
proc-self-syscall:exit=0
proc-self-wchan:exit=0
proc-subset-pid:exit=0
proc-tid0:exit=0
proc-uptime-001:exit=0
proc-uptime-002:exit=0
read:exit=0
self:exit=0
setns-dcache:exit=0
setns-sysvipc:exit=0
thread-self:exit=0
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
proc-uptime-001: proc-uptime-001.c:39: main: Assertion `i1 >= i0' failed.
Aborted (core dumped)
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
root@marvin-IdeaPad-3-15ITL6:/home/marvin/linux/kernel/linux_torvalds/tools/testing/selftests/proc# ./proc-uptime-001
The conclusion (to state the obvious) is that the GCC 12.2.0 optimisations are
not the culprit this time :-/
Thanks,
Mirsad
--
Mirsad Goran Todorovac
Sistem inženjer
Grafički fakultet | Akademija likovnih umjetnosti
Sveučilište u Zagrebu
--
System engineer
Faculty of Graphic Arts | Academy of Fine Arts
University of Zagreb, Republic of Croatia
The European Union
