MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
Summary:
MXBO settings can make system unusable, booting in a memtest-boot-loop only.
Symptom:
When the user changes the default boot-entry to „Memory Test“ the next and the future boots are set to boot into the „Memory Test“ boot-menu entry. To change the default entry back the user needs to choose another boot-menu entry within the grub-menu, open MXBO again and select another boot-entry to generate a new grub.cfg boot-menu. When the user selects “Menu timeout” as ‚0‘ and „Memory test“ as default „Boot to“ option, he will not presented with grub-menu but will always boot straight into „Memory Test“. By this he is presented with a „Memory Test“ boot-loop. By pressing “Esc” to cancel the memory test the system boots immediately into “Memory test” again. Mitigation:
- Instruct the user not to choose ‚0‘ menu-timeout, to avoid having the “unbreakable” boot-loop.
- Disable “Menu timeout” ‘0’ to avoid stuck within a boot-loop.
- Provide information how to access hidden grub-menu during boot-loop, if available.
- change the technical implementation of MXBO design by introducing one-time next-boot feature for memory test.
- Take out “Memory Test” boot-option from MXBO
Recommandation:
As grub does already provide the technical infrastructure for one-time boot options we recommend to utilize existing next one-time feature of grub.
Technical Hint:
Instead of using grub→GRUB_DEFAULT to set a fixed default boot entry, implement the GRUB-Environment feature to set default and next-ontime boot-entries.
→ grub→GRUB_DEFAULT=saved within /etc/default/grub
grub-set-default → to save default boot within grubenv as „saved_entry“
grub-reboot → to set next-ontime boot within grubenv as „next_entry“
grub-editenv /boot/grub/grubenv unset next_entry → remove next-ontime boot-entry
grub-editenv /boot/grub/grubenv list → to query grubenv for default and next-onetime boot-entries
WARNING:
Don’t try it out!
If you want to try out the magic memtest-boot-loop, you may end up within an unusable system.
Summary:
MXBO settings can make system unusable, booting in a memtest-boot-loop only.
Symptom:
When the user changes the default boot-entry to „Memory Test“ the next and the future boots are set to boot into the „Memory Test“ boot-menu entry. To change the default entry back the user needs to choose another boot-menu entry within the grub-menu, open MXBO again and select another boot-entry to generate a new grub.cfg boot-menu. When the user selects “Menu timeout” as ‚0‘ and „Memory test“ as default „Boot to“ option, he will not presented with grub-menu but will always boot straight into „Memory Test“. By this he is presented with a „Memory Test“ boot-loop. By pressing “Esc” to cancel the memory test the system boots immediately into “Memory test” again. Mitigation:
- Instruct the user not to choose ‚0‘ menu-timeout, to avoid having the “unbreakable” boot-loop.
- Disable “Menu timeout” ‘0’ to avoid stuck within a boot-loop.
- Provide information how to access hidden grub-menu during boot-loop, if available.
- change the technical implementation of MXBO design by introducing one-time next-boot feature for memory test.
- Take out “Memory Test” boot-option from MXBO
Recommandation:
As grub does already provide the technical infrastructure for one-time boot options we recommend to utilize existing next one-time feature of grub.
Technical Hint:
Instead of using grub→GRUB_DEFAULT to set a fixed default boot entry, implement the GRUB-Environment feature to set default and next-ontime boot-entries.
→ grub→GRUB_DEFAULT=saved within /etc/default/grub
grub-set-default → to save default boot within grubenv as „saved_entry“
grub-reboot → to set next-ontime boot within grubenv as „next_entry“
grub-editenv /boot/grub/grubenv unset next_entry → remove next-ontime boot-entry
grub-editenv /boot/grub/grubenv list → to query grubenv for default and next-onetime boot-entries
WARNING:
Don’t try it out!
If you want to try out the magic memtest-boot-loop, you may end up within an unusable system.
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Gigabyte Z77M-D3H, Intel Xeon E3-1240 V2 (Quad core), 32GB RAM,
GeForce GTX 770, Samsung SSD 850 EVO 500GB, Seagate Barracuda 4TB
GeForce GTX 770, Samsung SSD 850 EVO 500GB, Seagate Barracuda 4TB
- dolphin_oracle
- Developer
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- Joined: Sun Dec 16, 2007 1:17 pm
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
To those reading along, mxbo can change that setting from a live usb.
http://www.youtube.com/runwiththedolphin
lenovo ThinkPad X1 Extreme Gen 4 - MX-23
FYI: mx "test" repo is not the same thing as debian testing repo.
lenovo ThinkPad X1 Extreme Gen 4 - MX-23
FYI: mx "test" repo is not the same thing as debian testing repo.
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
Hmm, I guess that would be valid for every entry in GRUB that doesn't give access back to user to change the menu, for example Windows, if you select 0 and Windows then it will always boot to Windows. It's a feature of GRUB and I just propage it to MX Boot Options, now if people choose it it's kind of up to them, you have the option to shoot yourself in the foot but you don't have too.
You can boot however to LiveCD and fix it from there MX Boot Option should work from live environment, prompt you to select the partition where you have MX installed and you should be able to change the timeout to something else.
You can boot however to LiveCD and fix it from there MX Boot Option should work from live environment, prompt you to select the partition where you have MX installed and you should be able to change the timeout to something else.
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
Reply to comments:
default boot-entry instead of a one-time next-boot only. The current design is simply dangerous (memtest boot-”loop”), not user friendly (even with timeout non zero, he needs to change with MXBO the default again - awkward) and technical not necessary (use existing grub build-in for next only one-time boot)
--fehlix
- - Repairing with LiveMedia:
- - Menu-timeout ‘0’ into other OS/boot entry:
- - Use-Case Memtest-boot as default
default boot-entry instead of a one-time next-boot only. The current design is simply dangerous (memtest boot-”loop”), not user friendly (even with timeout non zero, he needs to change with MXBO the default again - awkward) and technical not necessary (use existing grub build-in for next only one-time boot)
--fehlix
Gigabyte Z77M-D3H, Intel Xeon E3-1240 V2 (Quad core), 32GB RAM,
GeForce GTX 770, Samsung SSD 850 EVO 500GB, Seagate Barracuda 4TB
GeForce GTX 770, Samsung SSD 850 EVO 500GB, Seagate Barracuda 4TB
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
OK, made the change to use "grub-reboot" option, but I saw at least once that exiting from Memtest didn't reset that, so I will also add manually the 5 second timeout in case somebody selects Memtest
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
I hope I understand the reason for this controversy...
Every Linux user should know that if the time is set to 0 seconds in the Grub_Menu, he will never see this Grub_Menu again.
To make this visible again, the shift key must be pressed and held simultaneously by pressing the power key of the computer.
This memtest shouldn't be any different.
Unfortunately I can't check this, because the MXBO tool is not offered to me during the update.
Did you get a scare about @felix's clues now?
Every Linux user should know that if the time is set to 0 seconds in the Grub_Menu, he will never see this Grub_Menu again.
To make this visible again, the shift key must be pressed and held simultaneously by pressing the power key of the computer.
This memtest shouldn't be any different.
Unfortunately I can't check this, because the MXBO tool is not offered to me during the update.
Did you get a scare about @felix's clues now?
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
Why is that, you are not on MX-17? It should be offered with an "apt-get full-upgrade" in any case I made the change and forced a 5 sec timeout on memtest just to make it easier for people to switch (update will probably come by the end of the day). Good point about holding Shift I forget about that.
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
grub-reboot will only work in conjuntion with GRUB_DEFAULT=saved, as both grubenv-entries for default and next-boot
will be ignore if GRUB_DEFAULT is not set to "saved" within generatd grub.cfg.
I.i if you had before GRUB_DEFAULT="XYZ" , you need to save "default-boot" and next-one-time boot using
grub-set-deault "XYZ" and grub-reboot 'Memory Test' also
and set GRUB_DEFAULT="saved" and generate grub.cfg.
If you already had GRUB_DEFAULT="saved", you would not need to regenrate grub.cfg ( better check within grub.cfg to be sure), but only update grubenv with grub-reboot 'Memory Test", as the defaul-entry "saved_entry") is already stored within grubenv .
Sorry for the rush ...
Gigabyte Z77M-D3H, Intel Xeon E3-1240 V2 (Quad core), 32GB RAM,
GeForce GTX 770, Samsung SSD 850 EVO 500GB, Seagate Barracuda 4TB
GeForce GTX 770, Samsung SSD 850 EVO 500GB, Seagate Barracuda 4TB
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
Doesn't seem to be correct at least in my trials, I left GRUB_DEFAULT to something else and used grub-reboot that set memtest as default at the next reboot. I'm satisfied with forcing a 5 seconds timeout when somebody selects memtest. It's a good failsafe should not confuse people too much.
Re: MX Boot Options – „Boot to“ Memory Test with Boot-“Loop“
surelyAdrian wrote:Why is that, you are not on MX-17?male wrote:Unfortunately I can't check this, because the MXBO tool is not offered to me during the update.
Code: Select all
inxi -r
Repos: Active apt repos in: /etc/apt/sources.list.d/antix.list
1: deb http://nl.mxrepo.com/antix/stretch stretch main
Active apt repos in: /etc/apt/sources.list.d/debian-stable-updates.list
1: deb http://ftp.de.debian.org/debian/ stretch-updates main contrib non-free
Active apt repos in: /etc/apt/sources.list.d/debian.list
1: deb http://ftp.de.debian.org/debian/ stretch main contrib non-free
2: deb http://security.debian.org/ stretch/updates main contrib non-free
Active apt repos in: /etc/apt/sources.list.d/mx.list
1: deb http://nl.mxrepo.com/mx/repo/ stretch main non-free
No active apt repos in: /etc/apt/sources.list.d/various.list