Bug 2422881 - Fedora will not not start from USB
Summary: Fedora will not not start from USB
Keywords:
Status: NEW
Alias: None
Product: Fedora
Classification: Fedora
Component: grub2
Version: 43
Hardware: x86_64
OS: Linux
unspecified
medium
Target Milestone: ---
Assignee: Nicolas Frayer
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2025-12-16 18:58 UTC by paolojr
Modified: 2026-01-26 18:01 UTC (History)
6 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Type: ---
Embargoed:


Attachments (Terms of Use)
T440_lshw (4.05 KB, text/plain)
2025-12-17 19:11 UTC, paolojr
no flags Details
T450_lshw (4.50 KB, text/plain)
2025-12-17 19:12 UTC, paolojr
no flags Details
original iso shasums (216 bytes, text/plain)
2025-12-18 17:51 UTC, paolojr
no flags Details
boot-max shasums (134 bytes, text/plain)
2025-12-18 17:51 UTC, paolojr
no flags Details
dd output (308.28 KB, image/png)
2025-12-18 18:01 UTC, paolojr
no flags Details
bios screen (3.98 MB, image/jpeg)
2025-12-18 18:05 UTC, paolojr
no flags Details
grub available commands (3.10 MB, image/jpeg)
2025-12-18 18:05 UTC, paolojr
no flags Details
grub debug commands (2.02 MB, image/jpeg)
2025-12-18 18:06 UTC, paolojr
no flags Details
grub terminal outputs (2.40 MB, image/jpeg)
2025-12-19 18:43 UTC, paolojr
no flags Details

Description paolojr 2025-12-16 18:58:18 UTC
running tests from: https://fedoraproject.org/wiki/Test_Day:2025-12-15_GRUB_out_of_memory_verification

Loaded fedora via Media Writer onto USB. Booted to USB on laptop (Lenovo ThinkPad T440), and brought to grub terminal.

Tested writing ISO to USB using Media Writer twice and results are the same

To note that existing laptop OS (on SSD) is Fedora 43 Workstation

Reproducible: Always

Steps to Reproduce:
1. write liveimage (https://fedorapeople.org/groups/qa/test_days/05673235-Fedora-Workstation-Live-x86_64-139891207.iso) to USB using Fedora Media Writer
2. boot PC from USB
3.
Actual Results:
Boots to grub terminal

Expected Results:
Boot to Fedora

Comment 1 Leo Sandoval 2025-12-16 20:04:41 UTC
Thanks for reporting it.

This is definitely something not expected nor desired. We ask you the following

1. On that machine, on a running system can you do 'lshw -short' place log here
2. Boot with the iso, on the grub terminal, type 'grub2-editenv - set debug=all,-lexer,-scripting' and go to the grub menu again and try booting fedora again. it is hard to copy and paste log but if possible take pics, specially on log's tail and attach these.
3. try this iso instead https://people.redhat.com/lsandova/oom/boot-max.iso which is no longer a LIVE iso image but an anaconda one containing exactly the same fix. We want to make sure both isos behave the same.

Comment 2 Leo Sandoval 2025-12-16 20:07:47 UTC
Also, for the point 1 above (lshw -short), please update (if not done yet) also this page. https://testdays.fedoraproject.org/testday/11

Comment 3 Leo Sandoval 2025-12-17 15:12:53 UTC
(In reply to Leo Sandoval from comment #1)
> Thanks for reporting it.
> 
> This is definitely something not expected nor desired. We ask you the
> following
> 
> 1. On that machine, on a running system can you do 'lshw -short' place log
> here
> 2. Boot with the iso, on the grub terminal, type 'grub2-editenv - set
> debug=all,-lexer,-scripting' and go to the grub menu again and try booting
> fedora again. it is hard to copy and paste log but if possible take pics,
> specially on log's tail and attach these.

the above point is not quite accurate, these are the correct instructions (thanks
to Nico F.)

- press 'c' at the boot menu
- add the line "set debug=all,-lexer,-scripting" then press Ctrl+x to boot
then share the logs.


> 3. try this iso instead https://people.redhat.com/lsandova/oom/boot-max.iso
> which is no longer a LIVE iso image but an anaconda one containing exactly
> the same fix. We want to make sure both isos behave the same.

Comment 4 paolojr 2025-12-17 19:11:57 UTC
Created attachment 2119066 [details]
T440_lshw

Comment 5 paolojr 2025-12-17 19:12:31 UTC
Created attachment 2119067 [details]
T450_lshw

Comment 6 paolojr 2025-12-17 19:50:36 UTC
Thanks for sharing the update.

In an effort to be more thorough, I have tested this flow on two machines: the existing Lenovo T440, and a Lenovo T450 (spare machines used for testing). Both have their `lshw -short` outputs attached, from within Fedora 43 Sway Spin.

I have used the original `.iso`, https://fedorapeople.org/groups/qa/test_days/05673235-Fedora-Workstation-Live-x86_64-139891207.iso, as well as the one you suggested (`boot-max.iso`), burned onto the USB with Fedora Media Writer.

The original `.iso`, after selecting the USB device in BIOS, boots straight into a grub terminal on both machines.

The suggested `.iso`, after selecting the USB device in BIOS, boots straight into a grub terminal on both machines.

I may have a failed USB drive, so have tried another. 

On this one, using the original `.iso`, both machines boot straight to the grub terminal.

Using the suggested `boot-max.iso`, both machines boot straight to the grub terminal.

Could this issue be with Fedora Media Writer? Shall I instead try `dd` for the `.iso` transfer to USB?

Comment 7 Leo Sandoval 2025-12-17 20:11:35 UTC
(In reply to paolojr from comment #6)
> Thanks for sharing the update.
> 
> In an effort to be more thorough, I have tested this flow on two machines:
> the existing Lenovo T440, and a Lenovo T450 (spare machines used for
> testing). Both have their `lshw -short` outputs attached, from within Fedora
> 43 Sway Spin.
> 
> I have used the original `.iso`,
> https://fedorapeople.org/groups/qa/test_days/05673235-Fedora-Workstation-
> Live-x86_64-139891207.iso, as well as the one you suggested
> (`boot-max.iso`), burned onto the USB with Fedora Media Writer.
> 
> The original `.iso`, after selecting the USB device in BIOS, boots straight
> into a grub terminal on both machines.
> 
> The suggested `.iso`, after selecting the USB device in BIOS, boots straight
> into a grub terminal on both machines.
> 
> I may have a failed USB drive, so have tried another. 
> 
> On this one, using the original `.iso`, both machines boot straight to the
> grub terminal.
> 
> Using the suggested `boot-max.iso`, both machines boot straight to the grub
> terminal.
> 
> Could this issue be with Fedora Media Writer? Shall I instead try `dd` for
> the `.iso` transfer to USB?

yes, give it a try please. if you get the same results (grub terminal instead of 
fedora live OS), then we should get the grub logs as indicated before. Also, 
please provide a checksum (md5sum or shasum) of the original iso.

Comment 8 paolojr 2025-12-18 17:51:32 UTC
Created attachment 2119179 [details]
original iso shasums

Comment 9 paolojr 2025-12-18 17:51:55 UTC
Created attachment 2119180 [details]
boot-max shasums

Comment 10 paolojr 2025-12-18 18:01:30 UTC
Created attachment 2119181 [details]
dd output

Comment 11 paolojr 2025-12-18 18:05:24 UTC
Created attachment 2119182 [details]
bios screen

Comment 12 paolojr 2025-12-18 18:05:47 UTC
Created attachment 2119183 [details]
grub available commands

Comment 13 paolojr 2025-12-18 18:06:11 UTC
Created attachment 2119184 [details]
grub debug commands

Comment 14 Leo Sandoval 2025-12-18 18:07:01 UTC
(In reply to paolojr from comment #8)
> Created attachment 2119179 [details]
> original iso shasums
these match with the ones I have, so sums are fine.

Comment 15 Leo Sandoval 2025-12-18 18:08:16 UTC
(In reply to paolojr from comment #13)
> Created attachment 2119184 [details]
> grub debug commands

remove double quotes

Comment 16 paolojr 2025-12-18 18:09:07 UTC
okay. got to test both iso's on the T450.

For the `shasum`, please see attached files for both `sha1` and `sha256` in their respective `.txt` files.

For the grub terminal, I wrote "set debug=all,-lexer,-scripting" and hit `enter`. What should I do afterward? I have attached some photos of the experience from the BIOS screen that goes straight to the grub terminal (not the grub menu) and available commands from there.

Also attached an image of the `dd` process for the related USB drive (/dev/sdb) when using the `boot-max.iso` for reference

Comment 17 Leo Sandoval 2025-12-18 18:17:10 UTC
(In reply to paolojr from comment #16)
> okay. got to test both iso's on the T450.
> 
> For the `shasum`, please see attached files for both `sha1` and `sha256` in
> their respective `.txt` files.

all looks fine, so no iso corrupted from your end.

> 
> For the grub terminal, I wrote "set debug=all,-lexer,-scripting" and hit
> `enter`. What should I do afterward? 

remove the quotes from the command, then hit enter and then Ctrl+x to boot

I have attached some photos of the
> experience from the BIOS screen that goes straight to the grub terminal (not
> the grub menu) and available commands from there.

right, this is not good. iso should bring you to the grub menu, where you can 'test & start fedora' or just 'start fedora'

> 
> Also attached an image of the `dd` process for the related USB drive
> (/dev/sdb) when using the `boot-max.iso` for reference

nice, looks good the sdb partitions after dd.

Comment 18 paolojr 2025-12-18 18:26:17 UTC
indeed, the grub menu does not appear.

i have removed the double quotes, hit enter. 

The tricky part is that `Ctrl-x`, and many other variations like: `Ctrl-Shift-x`, `Ctrl-Shift-Fn-x`, `Ctrl-Shift-Fn-F10` etc., does not boot to Fedora. The grub terminal remains

Comment 19 Leo Sandoval 2025-12-18 18:51:04 UTC
(In reply to paolojr from comment #18)
> indeed, the grub menu does not appear.
> 
> i have removed the double quotes, hit enter. 
> 
> The tricky part is that `Ctrl-x`, and many other variations like:
> `Ctrl-Shift-x`, `Ctrl-Shift-Fn-x`, `Ctrl-Shift-Fn-F10` etc., does not boot
> to Fedora. The grub terminal remains

I see, so once you set debug="debug,-lexer,-scripting", hit ESC key and then try boot.

Comment 20 paolojr 2025-12-19 18:43:41 UTC
Created attachment 2119265 [details]
grub terminal outputs

Comment 21 paolojr 2025-12-19 18:47:57 UTC
in still using the `boot-max.iso` and from the grub terminal on the Lenovo T450:
entered `set debug=all,-lexer,-scripting`, hit ESC to get a new grub prompt
attempted to check for the kernel to boot from, but either device (hd0 or hd1) shows "unknown filesystem"
the `boot` command requires a kernel file to boot from right?
see attached image for reference of these commands being executed

Comment 22 Leo Sandoval 2025-12-20 03:57:17 UTC
(In reply to paolojr from comment #21)
> in still using the `boot-max.iso` and from the grub terminal on the Lenovo
> T450:
> entered `set debug=all,-lexer,-scripting`, hit ESC to get a new grub prompt

just to be clear on this point: once you hit ESC, you do not see the grub menu?

> attempted to check for the kernel to boot from, but either device (hd0 or
> hd1) shows "unknown filesystem"
> the `boot` command requires a kernel file to boot from right?

right. It is linux followed by a initrd cmd. I will attach a pic.

> see attached image for reference of these commands being executed

Comment 23 Leo Sandoval 2025-12-20 03:58:31 UTC
(In reply to paolojr from comment #21)
> in still using the `boot-max.iso` and from the grub terminal on the Lenovo
> T450:
> entered `set debug=all,-lexer,-scripting`, hit ESC to get a new grub prompt

just to be clear on this point: once you hit ESC, you do not see the grub menu?

> attempted to check for the kernel to boot from, but either device (hd0 or
> hd1) shows "unknown filesystem"
> the `boot` command requires a kernel file to boot from right?

right. It is linux followed by a initrd cmd. I will attach a pic.

> see attached image for reference of these commands being executed

Comment 24 Leo Sandoval 2025-12-20 03:59:46 UTC
Created attachment 2119323 [details]
GRUB cmds shown when editing the 'Start Fedora' menu entry

Comment 25 paolojr 2025-12-20 18:19:02 UTC
(In reply to Leo Sandoval from comment #23)
> (In reply to paolojr from comment #21)
> > in still using the `boot-max.iso` and from the grub terminal on the Lenovo
> > T450:
> > entered `set debug=all,-lexer,-scripting`, hit ESC to get a new grub prompt
> 
> just to be clear on this point: once you hit ESC, you do not see the grub
> menu?

exactly. After clicking ESC (or ENTER), another grub terminal prompt appears, not the grub menu (to boot to Fedora)

> 
> > attempted to check for the kernel to boot from, but either device (hd0 or
> > hd1) shows "unknown filesystem"
> > the `boot` command requires a kernel file to boot from right?
> 
> right. It is linux followed by a initrd cmd. I will attach a pic.
> 
> > see attached image for reference of these commands being executed

after logging in via FAS, i cannot see the image ("...not authorized to access attachment").

Comment 26 Leo Sandoval 2026-01-26 18:01:06 UTC
Hi team,

we have a new fix [1] and hopefully this time would be the final one. A bit of resume
of this peculiar issue: the OOM issue is seen on those system with limited memory pool
so we try to increase the memory pool for grub_malloc [2] but hit other (unexpected) issues [3] so
[2] was reverted.

Before going into a second test-day for this OOM issue (if needed), I have proposed two testing scenarios below.
For both, please use a tesing HW (NEVER on your working desktop/lap) and DISABLE Secure boot (unsigned GRUB binaries
for the moment) temporaly.

- Option 1: ISO install (for those that cannot install Fedora due to OOM issues)
  0. Disable Secure boot
  1. Download the ISO [5] which contains the fix, flash it on a USB stick
  3. boot with it your HW. In theory the OOM would be seen here on those particular machines where OOM has been observed before
  4. If possible and your time allows, please install Fedora (use 'On the Network' in the Installation Source menu, this is just
     in case the auto-detect installation media fails). The reason we are asking for full installation is that last time we did not
     testers this step and we ended up with [3].
  5. Reboot your new Fedora System
  6. Follow instructions below (Option 2).  
  7. Share your results.

- Option 2: RPM install (for those already running a Fedora rawhide system)
  0. Disable Secure boot
  1. Boot your system
  2. Download the rpms[4], e.g. koji download-task --arch=x86_64 --arch=noarch 141497105
  3. install the rpms, e.g. sudo dnf install *.rpm
  4. Reboot
  5. Share results

[1] https://src.fedoraproject.org/rpms/grub2/pull-request/207
[2] https://src.fedoraproject.org/rpms/grub2/pull-request/198
[3] https://bugzilla.redhat.com/show_bug.cgi?id=2427945
[4] https://koji.fedoraproject.org/koji/taskinfo?taskID=141497105
[5] https://people.redhat.com/lsandova/oom/boot-efi-alloc-on-verifiers.iso


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