On Wed, Nov 12, 2025 at 9:11 PM Yanjun.Zhu <[email protected]> wrote: > > > On 11/12/25 5:41 PM, Yanjun.Zhu wrote: > > > > On 11/11/25 7:26 AM, Pasha Tatashin wrote: > >> On Mon, Nov 10, 2025 at 11:11 PM Zhu Yanjun <[email protected]> > >> wrote: > >>> In FC42, when I run "./luo_multi_session" > >>> > >>> # ./luo_multi_session > >>> # [STAGE 1] Starting pre-kexec setup for multi-session test... > >>> # [STAGE 1] Creating state file for next stage (2)... > >>> # [STAGE 1] Creating empty sessions 'multi-test-empty-1' and > >>> 'multi-test-empty-2'... > >>> # [STAGE 1] Creating session 'multi-test-files-1' with one memfd... > >>> # [STAGE 1] Creating session 'multi-test-files-2' with two memfds... > >>> # [STAGE 1] Executing kexec... > >>> > >>> Then the system hang. And via virt-viewer, a calltrace will appear. > >> Looks like mountroot fails, are you passing the same kernel parameters > >> as the during cold boot? > >> i.e. kexec -l -s --reuse-cmdline --initrd=[initramfs] [kernel] > > > > > > Thanks a lot. It can work now. The logs are as below: > > > > " > > > > # [STAGE 2] Starting post-kexec verification... > > # [STAGE 2] Retrieving all sessions... > > # [STAGE 2] Verifying contents of session 'multi-test-files-1'... > > # [STAGE 2] Verifying contents of session 'multi-test-files-2'... > > # [STAGE 2] Test data verified successfully. > > # [STAGE 2] Finalizing all test sessions... > > # [STAGE 2] Finalizing state session... > > # > > --- MULTI-SESSION KEXEC TEST PASSED --- > > " > > > > Yanjun.Zhu > > > Hi, Pasha > > In my tests, I found that luo_kexec_simple and luo_multi_session > currently depend on the glibc-static library. > If this library is not installed, build errors occur. > By making the following changes, luo_kexec_simple and luo_multi_session > would no longer depend on glibc-static, reducing external library > dependencies. > I am not sure whether you agree with these proposed changes. > > diff --git a/tools/testing/selftests/liveupdate/Makefile > b/tools/testing/selftests/liveupdate/Makefile > index 6ee6efeec62d..b226b9976150 100644 > --- a/tools/testing/selftests/liveupdate/Makefile > +++ b/tools/testing/selftests/liveupdate/Makefile > @@ -3,7 +3,6 @@ > KHDR_INCLUDES ?= -I../../../../usr/include > CFLAGS += -Wall -O2 -Wno-unused-function > CFLAGS += $(KHDR_INCLUDES) > -LDFLAGS += -static
Hi Yanjun, Thank you for testing. I prefer to keep the '-static' flag because these self-test files are not executed in the same environment where they are compiled but in a VM which might have a different userspace. Thank you, Pasha > OUTPUT ?= . > > # --- Test Configuration (Edit this section when adding new tests) --- > > Yanjun.Zhu > > > > > > >> > >> Pasha > >> > >>> The call trace is in the attachment. > >>> > >>> Yanjun.Zhu > >>> > >>> 在 2025/11/10 7:26, Pasha Tatashin 写道: > >>>> On Mon, Nov 10, 2025 at 8:16 AM Pratyush Yadav > >>>> <[email protected]> wrote: > >>>>> On Sun, Nov 09 2025, Zhu Yanjun wrote: > >>>>> > >>>>>> 在 2025/11/8 10:13, Pasha Tatashin 写道: > >>>>>>> On Fri, Nov 7, 2025 at 6:36 PM Yanjun.Zhu <[email protected]> > >>>>>>> wrote: > >>>>>>>> On 11/7/25 4:02 AM, Pasha Tatashin wrote: > >>>>>>>>> On Fri, Nov 7, 2025 at 7:00 AM Pasha Tatashin > >>>>>>>>> <[email protected]> wrote: > >>>>>>>>>>> Hi, Pasha > >>>>>>>>>>> > >>>>>>>>>>> In our previous discussion, we talked about counting the > >>>>>>>>>>> number of times > >>>>>>>>>>> the kernel is rebooted via kexec. At that time, you > >>>>>>>>>>> suggested adding a > >>>>>>>>>>> variable in debugfs to keep track of this count. > >>>>>>>>>>> However, since debugfs is now optional, where would be an > >>>>>>>>>>> appropriate > >>>>>>>>>>> place to store this variable? > >>>>>>>>>> It is an optional config and can still be enabled if the live > >>>>>>>>>> update > >>>>>>>>>> reboot number value needs to be accessed through debugfs. > >>>>>>>>>> However, > >>>>>>>>>> given that debugfs does not guarantee a stable interface, > >>>>>>>>>> tooling > >>>>>>>>>> should not be built to require these interfaces. > >>>>>>>>>> > >>>>>>>>>> In the WIP LUO [1] I have, I pr_info() the live update number > >>>>>>>>>> during > >>>>>>>>>> boot and also store it in the incoming LUO FDT tree, which > >>>>>>>>>> can also be > >>>>>>>>>> accessed through this optional debugfs interface. > >>>>>>>>>> > >>>>>>>>>> The pr_info message appears like this during boot: > >>>>>>>>>> [ 0.000000] luo: Retrieved live update data, liveupdate > >>>>>>>>>> number: 17 > >>>>>>>>>> > >>>>>>>>>> Pasha > >>>>>>>>> Forgot to add link to WIP LUOv5: > >>>>>>>>> [1] https://github.com/soleen/linux/tree/luo/v5rc04 > >>>>>>>> Thanks a lot. I’ve carefully read this commit: > >>>>>>>> https://github.com/soleen/linux/commit/60205b9a95c319dc9965f119303a1d83f0ff08fa. > >>>>>>>> > >>>>>>>> > >>>>>>>> To be honest, I’d like to run some tests with who/luo, > >>>>>>>> including the > >>>>>>>> selftest for kho/luo. Could you please share the steps with me? > >>>>>>>> > >>>>>>>> If the testing steps have already been documented somewhere, > >>>>>>>> could you > >>>>>>>> please share the link? > >>>>>>> Currently the test performs in-kernel tests for FLB data, it > >>>>>>> creates a > >>>>>>> number of FLB for every registered LUO file-handler, which at the > >>>>>>> moment is only memfd. > >>>>>>> > >>>>>>> It works together with any of the kexec based live update tests. In > >>>>>>> v5, I introduce two tests: > >>>>>>> luo_kexec_simple > >>>>>>> luo_multi_session > >>>>>>> > >>>>>>> For example, with luo_multi_session: > >>>>>> Hi, Pasha > >>>>>> > >>>>>> I enabled "CONFIG_LIVEUPDATE=y" > >>>>>> > >>>>>> # ./luo_multi_session > >>>>>> 1..0 # SKIP Failed to open /dev/liveupdate. Is the luo module > >>>>>> loaded? > >>>>>> > >>>>>> # ls /dev/liveupdate > >>>>>> ls: cannot access '/dev/liveupdate': No such file or directory > >>>>>> > >>>>>> # grep "LIVEUPDATE" -inrHI /boot/config-`uname -r` > >>>>>> /boot/config-next-20251107-luo+:349:CONFIG_LIVEUPDATE=y > >>>>>> /boot/config-next-20251107-luo+:11985:CONFIG_LIVEUPDATE_TEST=y > >>>>>> > >>>>>> I made tests on FC42. But /dev/liveupdate is missing. > >>>>> You need to add liveupdate=1 to your kernel cmdline to enable LUO and > >>>>> get /dev/liveupdate. > >>>> +1, kernel parameters require: kho=1 liveupdate=1 > >>>> > >>>>> Pasha, your LUO series doesn't add the liveupdate parameter to > >>>>> kernel-parameters.txt. I think it should be done in the next > >>>>> version to > >>>>> this parameter is discoverable. > >>>> Yeah, that is missing, I will update that in a standalone patch, or in > >>>> a next version. > >>>> > >>>> Thanks, > >>>> Pasha > >>> -- > >>> Best Regards, > >>> Yanjun.Zhu
