Guilherme, I tried to use your kernel, and it works!
Now I send you outputs you requested: $ uname -a Linux bntutest97 4.15.0-97-generic #98+TEST0000000v20200423b3-Ubuntu SMP Thu Apr 23 22:20:18 UTC 20 x86_64 x86_64 x86_64 GNU/Linux $ sudo kdump-config show udo kdump-config show DUMP_MODE: kdump USE_KDUMP: 1 KDUMP_SYSCTL: kernel.panic_on_oops=1 KDUMP_COREDIR: /var/crash crashkernel addr: 0x2c000000 /var/lib/kdump/vmlinuz: symbolic link to /boot/vmlinuz-4.15.0-97-generic kdump initrd: /var/lib/kdump/initrd.img: symbolic link to /var/lib/kdump/initrd.img-4.15.0-97-generic current state: ready to kdump kexec command: /sbin/kexec -p -s --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-97-generic root=UUID=cddaa45a-b277-465f-9410-3633976f020c ro reset_devices systemd.unit=kdump-tools-dump.service nr_cpus=1 irqpoll nousb ata_piix.prefer_ms_hyperv=0" --initrd=/var/lib/kdump/initrd.img /var/lib/kdump/vmlinuz -- 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: In Progress Status in linux source package in Bionic: In Progress 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 : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
