[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi yamato, thank you! Good news, this time the fix is working and I was able to kdump in my secureboot system. So, I'll move on and change title/component/description of this LP to proceed with the SRU - I hope next kernel (after 4.15.0-97) will have the fix =) In order to test the kernel, you must follow the below procedures (as root user): [I assume you don't have the proposed pocket enabled in your system, if so please disable it before testing] add-apt-repository ppa:gpiccoli/test1869672-2 apt-get update apt-get install linux-image-4.15.0-97-generic linux-modules-4.15.0-97-generic linux-modules-extra-4.15.0-97-generic Then, get the file: http://ppa.launchpad.net/gpiccoli/test1869672-2/ubuntu/dists/bionic/main/signed /linux-amd64/4.15.0-97.98+TEST000v20200423b3/signed.tar.gz Extract it and you'll see a file uefi.crt in "control/" folder. You can use the following command to extract its .DER key: openssl x509 -in uefi.crt -outform der -out cert.der Finally, I'm running "mokutil --import cert.der" to enroll the certificate on shim. After that, you must reboot and you firmware should present you a MOK utility to enroll the key (OVMF does, I need to access through serial console when booting). With all these steps, I was able to test successfully the kernel, and produced a kernel dump. Cheers, Guilherme ** Summary changed: - kdump kernel can't be loaded using kernel 4.15.0-76 + Kdump broken since 4.15.0-65 on secureboot - purgatory cannot load ** Also affects: linux (Ubuntu) Importance: Undecided Status: New ** No longer affects: makedumpfile (Ubuntu) ** Changed in: linux (Ubuntu) Status: New => In Progress ** Changed in: linux (Ubuntu Bionic) Status: New => In Progress ** Changed in: linux (Ubuntu) Importance: Undecided => High ** Changed in: linux (Ubuntu Bionic) Importance: Undecided => High ** Changed in: linux (Ubuntu) Assignee: (unassigned) => Guilherme G. Piccoli (gpiccoli) ** Changed in: linux (Ubuntu Bionic) Assignee: (unassigned) => Guilherme G. Piccoli (gpiccoli) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: Kdump broken since 4.15.0-65 on secureboot - purgatory cannot load To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Excellent! Of course I'll try your kernel. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi yamato, I'm sorry but I found yet another issue that I need to take care in my fix, hopefully by tomorrow I'll have a new test kernel. Also, I've noticed that in order to test PPA kernels on secure boot systems, you'll need to enroll the PPA sign key on shim, to make the kernel bootable - I'll present the details when kernel is ready. Thanks, Guilherme -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi yamato, thank you for the great report! I think I found the problem - can you test my fix proposal? It's just a matter of adding the following PPA to your system and installing the kernel: launchpad.net/~gpiccoli/+archive/ubuntu/test1869672 You can run the following commands in order to achieve that: sudo add-apt-repository ppa:gpiccoli/test1869672 sudo apt-get update sudo apt-get install linux-image-4.15.0-97-generic linux-modules-4.15.0-97-generic linux-modules-extra-4.15.0-97-generic After that, reboot into this new kernel, and test kdump load if possible. Also, please send me the output of the commands "uname -a" and "kdump-config show" when running the PPA kernel. Thanks again, Guilherme -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
** Changed in: makedumpfile (Ubuntu) Status: New => Confirmed ** Also affects: makedumpfile (Ubuntu Bionic) Importance: Undecided Status: New ** Changed in: makedumpfile (Ubuntu Bionic) Status: New => Confirmed ** Changed in: makedumpfile (Ubuntu Bionic) Status: Confirmed => In Progress ** Changed in: makedumpfile (Ubuntu) Status: Confirmed => In Progress ** Changed in: makedumpfile (Ubuntu Bionic) Importance: Undecided => High ** Changed in: makedumpfile (Ubuntu Bionic) Assignee: (unassigned) => Guilherme G. Piccoli (gpiccoli) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Guilherme, I'm so glad to hear it. Thanks a lot for your effort! -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi yamato, I have good news! Managed to reproduce this in a secure boot guest (after fighting with the keys hehe). There is an hypothesis of what's going on: one patch that was merged in -65 changed the way flags are set on purgatory, a piece of code used on kexec process. If we use kexec in a secure system, it must use the kexec_file_load syscall, which will rely in kernel purgatory. In no-secure-boot systems, the regular/old kexec_load flag is used, which loads the purgatory from kexec-tools. If the hypothesis is right, we need to figure why kernel 5.3-hwe works - there is a potential fix there based on my analysis, could be that one...but more tests are required. In sosreport dmesg, you can see the following messages, which are related: kexec: Undefined symbol: __stack_chk_fail kexec-bzImage64: Loading purgatory failed Work is ongoing, thanks again for the report and tests! Cheers, Guilherme -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Guilherme, Thank you for your support. Please feel free to tell me what I can do. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi yamato, thanks a lot for your thorough testing and for the sosreport. I'll try to reproduce here and analyze the sosreport. As soon as I have news, I'll get back to you. Cheers, Guilherme -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
First, I'll send sosreport on kernel 4.15.0-64. ** Attachment added: "sosreport on kernel 4.15.0-64." https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+attachment/5348454/+files/sosreport-advanced-kdumpon64-2020-04-07-mhgdfqe.tar.xz -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
I'll send the sosreport on kernel 4.15.0-76. ** Attachment added: "sosreport on kernel 4.15.0-76" https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+attachment/5348455/+files/sosreport-advanced-kdumpon76-2020-04-07-jyfwofm.tar.xz -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi Guilherme, Sure. I'll send my sosreport later. However, I believe this problem is not related with my hardware because this problem also occurs 3 different machines. * Advantec EPC-U2117 * Virtual Machine on VMware ESXi * UPS-APLX7-A20-0464 I write the procedure to find this problem. 1. Install 'Ubuntu server 18.04'. 2. Install 'kdump-tools' $ sudo apt install kdump-tools 3. create key and import after rebooting, the kdump kernel will enable when the secureboot is disabled. However, the kdump kernel will blocked regardless of the version of kernel. So I need to run these commands according to this. https://bugs.launchpad.net/ubuntu/+source/shim-signed/+bug/1840941 $ sudo openssl x509 -outform der -in /etc/ssl/certs/ca-certificates.crt -out new-ca.der $ sudo mokutil --import new-ca.der Inputing password will be required. 4. Reboot After rebooting, MOK management interface will be shown. Type Enter and select Enroll MOK > Yes, then input the password, then reboot 5. Check whether kdump-tools works or not. $ sudo systemctl status kdump-tools Using kernel 4.15.0-64: ● kdump-tools.service - Kernel crash dump capture service Loaded: loaded (/lib/systemd/system/kdump-tools.service; enabled; vendor preset: enabled) Active: active (exited) since Tue 2020-04-07 17:38:53 UTC; 41s ago Process: 878 ExecStart=/etc/init.d/kdump-tools start (code=exited, status=0/SUCCESS) Main PID: 878 (code=exited, status=0/SUCCESS) Apr 07 17:38:51 advanced systemd[1]: Starting Kernel crash dump capture service... Apr 07 17:38:52 advanced kdump-tools[878]: Starting kdump-tools: * Creating symlink /var/lib/kdump/vmlinuz Apr 07 17:38:52 advanced kdump-tools[878]: * Creating symlink /var/lib/kdump/initrd.img Apr 07 17:38:52 advanced kdump-tools[878]: * loaded kdump kernel Apr 07 17:38:52 advanced kdump-tools[1029]: loaded kdump kernel Apr 07 17:38:53 advanced systemd[1]: Started Kernel crash dump capture service. Using kernel 4.15.0-76: ● kdump-tools.service - Kernel crash dump capture service Loaded: loaded (/lib/systemd/system/kdump-tools.service; enabled; vendor preset: enabled) Active: active (exited) since Tue 2020-04-07 16:59:01 UTC; 25min ago Main PID: 889 (code=exited, status=0/SUCCESS) Tasks: 0 (limit: 4915) CGroup: /system.slice/kdump-tools.service Apr 07 16:58:42 advanced systemd[1]: Starting Kernel crash dump capture service... Apr 07 16:58:43 advanced kdump-tools[889]: Starting kdump-tools: * Creating symlink /var/lib/kdump/vmlinuz Apr 07 16:58:43 advanced kdump-tools[889]: kdump-tools: Generating /var/lib/kdump/initrd.img-4.15.0-76-lowlatency Apr 07 16:59:01 advanced kdump-tools[889]: * Creating symlink /var/lib/kdump/initrd.img Apr 07 16:59:01 advanced kdump-tools[889]: kexec_file_load failed: Exec format error Apr 07 16:59:01 advanced kdump-tools[889]: * failed to load kdump kernel Apr 07 16:59:01 advanced systemd[1]: Started Kernel crash dump capture service. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
By the way, I found the new kernel 4.15.0-96 is available. I also tried, but the problem won't be fixed 4.15.0-45 -> OK 4.15.0-64 -> OK * 4.15.0-65 -> NG * 4.15.0-66 -> NG * 4.15.0-69 -> NG * 4.15.0-70 -> NG * 4.15.0-72 -> NG * 4.15.0-74 -> NG 4.15.0-76 -> NG 4.15.0-88 -> NG 4.15.0-91 -> NG ** 4.15.0-96 -> NG 4.18.0-15 -> OK -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi yamato, thanks a lot for your help! This greatly reduced the search scope. There's one more thing I need from you - can you collect a sosreport from your system? This way I can try to mimic your system here the best I can. Thanks in advance, Guilherme -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Guilherme, > can you test the in-between kernel versions, so we can narrow down when the problem was introduced? Of course! I have tesed each kernels. Please check the result. It seems that the problem occurs from 4.15.0-65. 4.15.0-45 -> OK 4.15.0-64 -> OK * 4.15.0-65 -> NG * 4.15.0-66 -> NG * 4.15.0-69 -> NG * 4.15.0-70 -> NG * 4.15.0-72 -> NG * 4.15.0-74 -> NG 4.15.0-76 -> NG 4.15.0-88 -> NG 4.15.0-91 -> NG 4.18.0-15 -> OK -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi yamato, thank you for the report and prompt test! So, I need to setup a guest with secureboot, I don't have it at hand. Meanwhile, can you test the in-between kernel versions, so we can narrow down when the problem was introduced? The versions we had released in Bionic between -64 and -76 are: 4.15.0-65-generic, 4.15.0-66-generic, 4.15.0-69-generic, 4.15.0-70-generic and 4.15.0-72-generic. If you could test with them all, certainly that would speed-up the resolution, while I work a VM with secureboot support. Thanks again, Guilherme ** Changed in: makedumpfile (Ubuntu) Assignee: (unassigned) => Guilherme G. Piccoli (gpiccoli) ** Changed in: makedumpfile (Ubuntu) Importance: Undecided => High -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Guilherme,, Thank you for your reply! > Does your system have secureboot enabled? Yes. I confirmed kdump works without secureboot, but we need it. > Also, can you test in a recent kernel, like 4.15.0-91? Yes, I also tried to use 4.15.0-91 and the other. The results: 4.15.0-45 -> OK 4.15.0-64 -> OK 4.15.0-76 -> NG 4.15.0-88 -> NG 4.15.0-91 -> NG 4.18.0-15 -> OK -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
Hi yamato, thanks for the bug report! Does your system have secureboot enabled? Also, can you test in a recent kernel, like 4.15.0-91? Thanks in advance, Guilherme -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1869672] Re: kdump kernel can't be loaded using kernel 4.15.0-76
** Description changed: Thank you for reading this report. This may caused by bugs in kernel, not in kdump. If so, I will report this to kernel team. I need your comment to solve this. [Impact] * Kdump kernel can't be loaded using linux kernel 4.15.0-76. [Environment] Description:Ubuntu 18.04.4 LTS Release:18.04 uname: Linux ubuntu 4.15.0-76-generic #86-Ubuntu SMP Fri Jan 17 17:24:28 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux Secure boot is enabled. - Versions: * kexec-tools/bionic-updates,now 1:2.0.16-1ubuntu1.1 * kdump-tools/bionic-updates,now 1:1.6.5-1ubuntu1~18.04.4 [Test case] 1)After OS booted, run systemctl status kdump-tools shows these messages below: ● kdump-tools.service - Kernel crash dump capture service Loaded: loaded (/lib/systemd/system/kdump-tools.service; enabled; vendor preset: enabled) Active: active (exited) since Fri 2020-03-27 16:40:31 JST; 5min ago Process: 895 ExecStart=/etc/init.d/kdump-tools start (code=exited, status=0/SUCCESS) Main PID: 895 (code=exited, status=0/SUCCESS) Mar 27 16:40:31 ubuntu systemd[1]: Starting Kernel crash dump capture service... Mar 27 16:40:31 ubuntu kdump-tools[895]: Starting kdump-tools: * Creating symlink /var/lib/kdump/vmlinuz Mar 27 16:40:31 ubuntu kdump-tools[895]: * Creating symlink /var/lib/kdump/initrd.img Mar 27 16:40:31 ubuntu kdump-tools[895]: kexec_file_load failed: Exec format error Mar 27 16:40:31 ubuntu kdump-tools[895]: * failed to load kdump kernel Mar 27 16:40:31 ubuntu systemd[1]: Started Kernel crash dump capture service. 2)Run kexec directly: $ sudo /sbin/kexec -p --command-line="/boot/vmlinuz-4.15.0-76-generic root=UUID=29a89ad8-8923-435e-a88c-aaf5cb379568 ro mce=ignore_ce reset_devices systemd.unit=kdump-tools-dump.service nr_cpus=1 irqpoll nousb ata_piix.prefer_ms_hyperv=0" --initrd=/boot/initrd.img-4.15.0-76-generic /boot/vmlinuz-4.15.0-64-generic Then,these messages are shown: Cannot open /proc/kcore: Operation not permitted Cannot read /proc/kcore: Operation not permitted Cannot load /boot/vmlinuz-4.15.0-76-generic On dmesg, these messages are shown: [ 538.524718] Lockdown: /proc/kcore is restricted; see man kernel_lockdown.7 3) Changing OS kernel to older one(I used 4.15.0-64), kdump kernel can be loaded. $ sudo systemctl status kdump-tools ● kdump-tools.service - Kernel crash dump capture service Loaded: loaded (/lib/systemd/system/kdump-tools.service; enabled; vendor preset: enabled) Active: active (exited) since Wed 2020-03-25 13:39:03 JST; 5 days ago Main PID: 832 (code=exited, status=0/SUCCESS) Tasks: 0 (limit: 4915) CGroup: /system.slice/kdump-tools.service - Mar 25 13:39:02 ctrl-edgen systemd[1]: Starting Kernel crash dump capture service... - Mar 25 13:39:02 ctrl-edgen kdump-tools[832]: Starting kdump-tools: * Creating symlink /var/lib/kdump/vmlinuz - Mar 25 13:39:02 ctrl-edgen kdump-tools[832]: * Creating symlink /var/lib/kdump/initrd.img - Mar 25 13:39:03 ctrl-edgen kdump-tools[832]: * loaded kdump kernel - Mar 25 13:39:03 ctrl-edgen kdump-tools[938]: loaded kdump kernel - Mar 25 13:39:03 ctrl-edgen systemd[1]: Started Kernel crash dump capture service. + Mar 25 13:39:02 ubuntu systemd[1]: Starting Kernel crash dump capture service... + Mar 25 13:39:02 ubuntu kdump-tools[832]: Starting kdump-tools: * Creating symlink /var/lib/kdump/vmlinuz + Mar 25 13:39:02 ubuntu kdump-tools[832]: * Creating symlink /var/lib/kdump/initrd.img + Mar 25 13:39:03 ubuntu kdump-tools[832]: * loaded kdump kernel + Mar 25 13:39:03 ubuntu kdump-tools[938]: loaded kdump kernel + Mar 25 13:39:03 ubuntu systemd[1]: Started Kernel crash dump capture service. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: kdump kernel can't be loaded using kernel 4.15.0-76 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1869672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
