CentOS - Jul 2020 - After update to 8 (2004) ... system is unbootable - UEFI Secure boot

Am 16.06.20 um 22:04 schrieb Fabian Arrotin:
> On 16/06/2020 15:06, Leon Fauster via CentOS wrote:
>> Hi all,
>>
>> I updated a Dell XPS laptop from CentOS 8.1 (1911) to 8.2 (2004).
>>
>> Installed kernels are
>> kernel-4.18.0-147.5.1.el8_1.x86_64
>> kernel-4.18.0-147.8.1.el8_1.x86_64
>> kernel-4.18.0-193.6.3.el8_2.x86_64
>>
>> Unfortunately I can not boot into the latest
>> kernel-4.18.0-193.6.3.el8_2.x86_64.
>>
>> After grub2 screen I only see following line:
>>
>> EFI stub: UEFI Secure Boot is enabled
>>
>> Booting into the older kernel is still possible. The
>> above line appears and after that the normal kernel
>> output scrolls over the screen (rhgb quiet disabled).
>>
>> Is the new kernel correctly signed?
>>
>> What can I do?
>>
>> -- 
>> Thanks
>> Leon
> 
> Hi Leon,
> 
> Don't think that it's due to secureboot, as on my work laptop
(thinkpad
> t490s), I have secureboot on, and kernel working fine.
> 
> OTOH, on my family laptop (also in secureboot mode), when I updated from
> 8.1.1011 to 8.2.2004, laptop became unresponsive during the
> microcode_ctl update (in scriptlet) and after that it auto-reset itself
> , so in the middle of the whole rpm transaction.
> I tried to recover it but it was to a point where it was faster to just
> reinstall from scratch with 8.2.2004, which I did ... and in gnome,
> everything was fine, etc (adding repo, pkgs) but then on the *same*
> kernel it was installed with, just tried a reboot, and nothing  : grub
> shows menu, you select kernel and on upper left there is only cursor
> (fixed) and nothing happens ..
> 
> I'll try to diagnose what's the issue as actually that means
troubles
> with family using that laptop :)

Did you got managed to boot kernel-4.18.0-193.14.2.el8_2 or a newer one?
I must still boot into kernel-4.18.0-147.8.1.el8_1.x86_64 ... and with 
the upcoming new kernel that depends on a new shim and grub2 package I 
wonder about the implications for my XPS hardware ...

--
Thanks,
Leon

On 29/07/2020 19:43, Leon Fauster via CentOS wrote:
> 
> Did you got managed to boot kernel-4.18.0-193.14.2.el8_2 or a newer one?
> I must still boot into kernel-4.18.0-147.8.1.el8_1.x86_64 ... and with 
> the upcoming new kernel that depends on a new shim and grub2 package I 
> wonder about the implications for my XPS hardware ...
> 
The following article discusses a way to add a hash for older kernels to 
the Allow List that should allow older kernels to continue to boot:

https://access.redhat.com/security/vulnerabilities/grub2bootloader

Quoting...

Red Hat Enterprise Linux 8

Due to hardening within the kernel, which is released as part of these 
updates, previous Red Hat Enterprise Linux 8 kernel versions have not 
been added to shim?s allow list. If you are running with Secure Boot 
enabled, and the user needs to boot to an older kernel version, its hash 
must be manually enrolled into the trust list. This is achieved by 
executing the following commands:

# pesign -P -h -i /boot/vmlinuz-<version>

# mokutil --import-hash <hash value returned from pesign>

# reboot

Am 29.07.20 um 20:54 schrieb Phil Perry:
> On 29/07/2020 19:43, Leon Fauster via CentOS wrote:
>>
>> Did you got managed to boot kernel-4.18.0-193.14.2.el8_2 or a newer
one?
>> I must still boot into kernel-4.18.0-147.8.1.el8_1.x86_64 ... and with 
>> the upcoming new kernel that depends on a new shim and grub2 package I 
>> wonder about the implications for my XPS hardware ...
>>
> 
> The following article discusses a way to add a hash for older kernels to 
> the Allow List that should allow older kernels to continue to boot:
> 
> https://access.redhat.com/security/vulnerabilities/grub2bootloader
> 
> Quoting...
> 
> Red Hat Enterprise Linux 8
> 
> Due to hardening within the kernel, which is released as part of these 
> updates, previous Red Hat Enterprise Linux 8 kernel versions have not 
> been added to shim?s allow list. If you are running with Secure Boot 
> enabled, and the user needs to boot to an older kernel version, its hash 
> must be manually enrolled into the trust list. This is achieved by 
> executing the following commands:
> 
> # pesign -P -h -i /boot/vmlinuz-<version>
> 
> # mokutil --import-hash <hash value returned from pesign>
> 
> # reboot
> 
Thank you very much, Phil! This helps to boot the old kernel.

Also the newer kernel-4.18.0-193.14.2.el8_2.x86_64 can not boot on
this notebook (Intel i7-8750H (06-9e-0a) / DELL XPS 15 9570).

I had open a bug report already (not public as usual for kernels)

https://bugzilla.redhat.com/show_bug.cgi?id=1848743

Does someone else has this problem?

--
Leon

Am 29.07.20 um 20:43 schrieb Leon Fauster:
> Am 16.06.20 um 22:04 schrieb Fabian Arrotin:
>> On 16/06/2020 15:06, Leon Fauster via CentOS wrote:
>>> Hi all,
>>>
>>> I updated a Dell XPS laptop from CentOS 8.1 (1911) to 8.2 (2004).
>>>
>>> Installed kernels are
>>> kernel-4.18.0-147.5.1.el8_1.x86_64
>>> kernel-4.18.0-147.8.1.el8_1.x86_64
>>> kernel-4.18.0-193.6.3.el8_2.x86_64
>>>
>>> Unfortunately I can not boot into the latest
>>> kernel-4.18.0-193.6.3.el8_2.x86_64.
>>>
>>> After grub2 screen I only see following line:
>>>
>>> EFI stub: UEFI Secure Boot is enabled
>>>
>>> Booting into the older kernel is still possible. The
>>> above line appears and after that the normal kernel
>>> output scrolls over the screen (rhgb quiet disabled).
>>>
>>> Is the new kernel correctly signed?
>>>
>>> What can I do?
>>>
>>> -- 
>>> Thanks
>>> Leon
>>
>> Hi Leon,
>>
>> Don't think that it's due to secureboot, as on my work laptop
(thinkpad
>> t490s), I have secureboot on, and kernel working fine.
>>
>> OTOH, on my family laptop (also in secureboot mode), when I updated
from
>> 8.1.1011 to 8.2.2004, laptop became unresponsive during the
>> microcode_ctl update (in scriptlet) and after that it auto-reset itself
>> , so in the middle of the whole rpm transaction.
>> I tried to recover it but it was to a point where it was faster to just
>> reinstall from scratch with 8.2.2004, which I did ... and in gnome,
>> everything was fine, etc (adding repo, pkgs) but then on the *same*
>> kernel it was installed with, just tried a reboot, and nothing? : grub
>> shows menu, you select kernel and on upper left there is only cursor
>> (fixed) and nothing happens ..
>>
>> I'll try to diagnose what's the issue as actually that means
troubles
>> with family using that laptop :)
> 
> 
> Did you got managed to boot kernel-4.18.0-193.14.2.el8_2 or a newer one?
> I must still boot into kernel-4.18.0-147.8.1.el8_1.x86_64 ... and with 
> the upcoming new kernel that depends on a new shim and grub2 package I 
> wonder about the implications for my XPS hardware ...
> 

JFYI: latest (kernel-4.18.0-227.el8.x86_64) 8-stream kernel is
bootable on this machine ... (full updated (C8.2.2004) with latest
shim, grub2 stuff. Just the kernel is from 8-stream) ...

--
Leon