• Bug#1106185: intel-microcode: Kernel panic on boot: Dell T5600 with Int

    From Alban Browaeys@1:229/2 to [email protected] on Mon May 26 02:50:01 2025
    From: [email protected]

    On Tue, 20 May 2025 21:30:28 +0200 Ayke Halder
    <[email protected]> wrote:
    Package: intel-microcode
    Version: 3.20250512.1~deb11u1
    Severity: critical
    Justification: breaks the whole system
    X-Debbugs-Cc: [email protected]

    Dear Maintainer,

    after installation of intel-microcode 3.20250512.1~deb11u1 on a Dell
    T5600 with
    dual Intel Xeon E5-2660 the system becomes totally unbootable on
    kernel
    6.1.0-0.deb11.21-amd64:

    ``
    0.921425] Kernel panic - not syncing: UFS: Unable to mount root fs on
    unknown-
    block(0,0)


    https://askubuntu.com/questions/41930/kernel-panic-not-syncing-vfs-unable-to-mount-root-fs-on-unknown-block0-0
    and https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=906584 clues at a
    missing initramfs.
    Do you have enough free space in /boot (is /boot is a separate
    partition?)
    What is the outcome of update-initramfs with the offending microcode
    and kernel? (no need to boot).
    Also you could try to load the kernel and initramfs with qemu to test
    if they are correct after update-initramfs.

    Unable to mount root fs means that the / partition could not be
    mounted, likely because the drivers to do so are in the initramfs and
    either the initramfs failed to generate.

    to create a missing initramfs
    update-initramfs -c -k <kernel_version>

    to update an initramfs
    update-initramfs -u -k <kernel_version>

    though it seems unlikely to be a space issue as 3.20250211.1 is around
    9MB while 3.20250512.1~deb11u1is around 11MB it could be the old kernel initramfs plus the new one overflow the partition size.

    But it is also very unlikely that a CPU bug would always fails at the
    mount root fs step.

    Also have you tried 3.20250512.1~deb12u1? (note the deb12u1 instead of
    deb11u1 in your report)


    0.921462] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.1.0-0.deb11.21-
    amd64 #1
    Debian 6.1.90-1~bpo11+1
    0.921495] Hardware name: Dell Inc. Precision T5600/XXXXX, BIOS A19
    06/30/2019
    0.921521] Call Trace:
    0.921535] <TASK>
    0.921547] dump_stack_lvl+0x45/0x5e
    0.921573] panic+0x10c/0x2b6
    0.921593] mount_block_root+0x1c6/0x1d9
    0.921616] prepare_namespace+0x136/0x165
    0.921633] kernel_init_freeable+0x25d/0x287
    0.921651] ? rest_init+0xd0/0xd0
    0.921669] kernel_init+0x16/0x130
    0.921685] ret_from_fork+0x22/0x30
    0.921705] </TASK>
    0.921790] Kernel Offset: 0x4e00000 from Oxffffffff81000000
    (relocation range:
    0xffffffff80000000-0xfffffffffffffff)
    0.921827] ---[ end Kernel panic - not syncing: UFS: Unable to mount
    root fs on
    unknown-block(0,0) ]---
    ``

    On kernel 6.1.0-0.deb11.17-amd64 and intel-microcode
    3.20250512.1~deb11u1 the
    system is kind of bootable but shows severe errors.

    A roll back to intel-microcode 3.20250211.1~deb11u1 fixes the problem
    for
    kernel 6.1.0-0.deb11.17-amd64 and 6.1.0-0.deb11.21-amd64.


    -- System Information:
    Debian Release: 11.11
       APT prefers oldstable-updates
       APT policy: (500, 'oldstable-updates'), (500, 'oldstable-
    security'), (500,
    'oldstable')
    Architecture: amd64 (x86_64)

    Kernel: Linux 6.1.0-0.deb11.21-amd64 (SMP w/32 CPU threads; PREEMPT)
    Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
    Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8),
    LANGUAGE not
    set
    Shell: /bin/sh linked to /usr/bin/dash
    Init: systemd (via /run/systemd/system)
    LSM: AppArmor: enabled

    Versions of packages intel-microcode depends on:
    ii  iucode-tool  2.3.1-1


    Cheers,
    Alban

    --- SoupGate-Win32 v1.05
    * Origin: you cannot sedate... all the things you hate (1:229/2)