Guilherme, I've confirmed the kdump works correctly!
yam@ubuntu18:~$ 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 Thu 2020-05-28 01:10:15 UTC; 5min ago Process: 540 ExecStart=/etc/init.d/kdump-tools start (code=exited, status=0/SUCCESS) Main PID: 540 (code=exited, status=0/SUCCESS) May 28 01:10:12 ubuntu18 systemd[1]: Starting Kernel crash dump capture service... May 28 01:10:13 ubuntu18 kdump-tools[540]: Starting kdump-tools: * Creating symlink /var/lib/kdump/vmlinuz May 28 01:10:13 ubuntu18 kdump-tools[540]: * Creating symlink /var/lib/kdump/initrd.img May 28 01:10:15 ubuntu18 kdump-tools[540]: * loaded kdump kernel May 28 01:10:15 ubuntu18 kdump-tools[764]: loaded kdump kernel May 28 01:10:15 ubuntu18 systemd[1]: Started Kernel crash dump capture service. yam@ubuntu18:~$ uname -a Linux ubuntu18 4.15.0-102-generic #103-Ubuntu SMP Fri May 15 15:22:18 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux yam@ubuntu18:~$ sudo lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 18.04.4 LTS Release: 18.04 Codename: bionic -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1869672 Title: Kdump broken since 4.15.0-65 on secureboot - purgatory cannot load Status in linux package in Ubuntu: Fix Committed Status in linux source package in Bionic: Fix Committed Bug description: [Impact] * Kdump kernel can't be loaded using Linux kernel 4.15.0-65 and newer on Bionic; kexec fails to load using the "new" kexec_file_load() syscall, showing the following messages in dmesg: kexec: Undefined symbol: __stack_chk_fail kexec-bzImage64: Loading purgatory failed * Reason for this was that backport from upstream commit b059f801a937 ("x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS") makes use of a config option guard that wasn't backported to Ubuntu 4.15.x series. * Also, we found another related issue, an undefined memcpy() symbol, that was related to the above patch too. We propose here a specific fix for Bionic, in the form of the patch attached in comment #18. [Test case] * Basically the test consists in booting a signed kernel in a secure boot environment (this is required given Ubuntu kernel is built with CONFIG_KEXEC_VERIFY_SIG so to use kexec_file_load() we must be in a proper signed/secure booted system). It works until 4.15.0-64, and starts to fail after this release, until the current proposed version 4.15.0-97. We can also check kdump-tools service in the failing case, which shows: systemctl status kdump-tools [...] kdump-tools[895]: Starting kdump-tools: * Creating symlink /var/lib/kdump/vmlinuz kdump-tools[895]: * Creating symlink /var/lib/kdump/initrd.img kdump-tools[895]: kexec_file_load failed: Exec format error kdump-tools[895]: * failed to load kdump kernel [...] * With the patch attached in the LP, it works normally again and I was able to collect a kdump. [Regression potential] * Given the patch is quite simple and fixes the build of purgatory, I think the regression potential is low. One potential regression in future would be on backports to purgatory Makefile, making them more difficult/prone to errors; given purgatory is a pretty untouchable code, I consider the regression potential here to be really low. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1869672/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
