Uploaded image for project: 'RHEL'
  1. RHEL
  2. RHEL-131910

[kdump][CVM][Azure] reboot takes long time after vmcore saving finishes on Intel TDX

Linking RHIVOS CVEs to...Migration: Automation ...RHELPRIO AssignedTeam ...SWIFT: POC ConversionSync from "Extern...XMLWordPrintable

    • Icon: Bug Bug
    • Resolution: Unresolved
    • Icon: Undefined Undefined
    • None
    • rhel-10.2
    • kdump-utils
    • None
    • None
    • rhel-kernel-debug
    • 0
    • False
    • False
    • Hide

      None

      Show
      None
    • None
    • None
    • None
    • None
    • Unspecified
    • Unspecified
    • Unspecified
    • None

      What were you trying to do that didn't work?

      On Azure Intel TDX CVM, after vmcore saving finishes, the system is stuck at reboot for over 20min. The last serial console is like this:

               Starting Kdump Vmcore Save Service...
      [    1.838152] systemd[1]: Starting Kdump Vmcore Save Service...
      [    1.870561] kdump[385]: Kdump is using the default log level(3).
      [    1.969652] kdump[429]: saving to /sysroot/var/crash/127.0.0.1-2025-11-28-06:03:43/
      [    2.071275] kdump[434]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2025-11-28-06:03:43/
      [    2.101940] kdump[440]: saving vmcore-dmesg.txt complete
      [    2.107740] kdump[442]: saving vmcore
      [    5.632350] rngd[276]: [jitter]: Unable to obtain AES key, disabling JITTER source
      [    5.636489] rngd[276]: [jitter]: Initialization Failed
      [    5.638621] rngd[276]: [namedpipe]: Initialization Failed
      Copying data                                      : [100.0 %] \           eta: 0s
      [    6.394962] kdump.sh[443]: The dumpfile is saved to /sysroot/var/crash/127.0.0.1-2025-11-28-06:03:43//vmcore-incomplete.
      [    6.400487] kdump.sh[443]: makedumpfile Completed.
      [    6.437292] kdump[447]: saving vmcore complete
      [    6.442230] kdump[449]: saving the /run/initramfs/kexec-dmesg.log to /sysroot/var/crash/127.0.0.1-2025-11-28-06:03:43//
      [    6.462150] kdump[455]: Executing final action systemctl reboot -f
      [    6.470902] systemd[1]: Shutting down.
      [    6.507308] rngd[276]: [hwrng ]: Shutting down
      [    6.509572] rngd[276]: [rdrand]: Shutting down
      [    6.579070] systemd-shutdown[1]: Could not detach loopback /dev/loop0: Device or resource busy
      [    6.585209] systemd-shutdown[1]: Failed to finalize loop devices, ignoring.
      [    6.603951] reboot: Restarting system 

      This only happens to Intel TDX CVM but not to AMD SNP.

      The system is fine after it finally reboots.

      This does not happen at ordinary reboots.

       

      What is the impact of this issue to you?

      No functional impact found so far.

      Please provide the package NVR for which the bug is seen:

       kernel-6.12.0-164.el10

      How reproducible is this bug?:

      Always

      Steps to reproduce

      1.  # echo c > /proc/sysrq-trigger
      2.  
      3.  

      Expected results

      Reboot happens in less than a minute on SNP CVM.

      Actual results

              kdump-bugs@redhat.com kdump team
              litian@redhat.com Li Tian
              kdump team kdump team
              kdump team kdump team
              Votes:
              0 Vote for this issue
              Watchers:
              7 Start watching this issue

                Created:
                Updated: