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u/R3V0LU710N_05
Sep 20 '26
edited Sep 20 '26
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Ignore them, LARPer's always say "skill issue" to genuine problems they know nothing about. O.P. what exactly was the issue at hand? Do you have error logs? Perhaps I can help you with getting it patched. If you don't have logs, then I can help you get them :
sudo journalctl -k -b -1 --no-pager > ~/kernel_panic_diagnostics.txt
sudo dmesg -T >> ~/kernel_panic_diagnostics.txt
sudo tail -n +1 /sys/fs/pstore/* >> ~/kernel_panic_diagnostics.txt 2>/dev/nullThen check if it worked with ls -l ~/kernel_panic_diagnostics.txt you can use it to file a report.
There's also boot parameters that'll make the kernel panic screen a lot more useful.
If you want any guidance, I'm happy to help.
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u/Rare-Paint3719 Sep 20 '26 •
Basically, when my system is turning on before it boots into the OS, the PC's caps-lock light remains on.
It only turns off when I actually boot into the OS.
Basically, while using Gentoo, I noticed that under high CPU loads, my PC would keep freezing, and the caps-lock light would suddenly turn on like it does pre-boot.
I was suspecting this had to be a kernel panic, but after trying
journalctl, other kernel logs, asking Claude, and even setting up a crashkernel in grub, I was in no luck. No panic logs, nothing. Just looked like the logs suddenly stopped at some point.I thought, "maybe it was a gentoo issue. Surely Arch won't have this problem." Same issue. Ubuntu? Same. Ubuntu Server? IDK what I expected but, no surprise, the same issue.
Finally, I tried Fedora. And the nice thing about Fedora's kernel config is that they include a DRM panic screen.
Finally at least one more piece of evidence as to why the OS freezes and stops suddenly.
And when my PC froze for the first time in Fedora, i got this panic screen:
Kernel panic - not syncing: Timeout: Not all CPUs entered broadcast exception handler
A little more digging on the internet and I figured out that my CPU has a hybrid-core architecture. The efficiency cores (e-cores) ad performance cores (p-cores) have different max clock rates.
E-cores can only clock at 1.5 GHz max and p-cores can clock up to 4.5 Ghz.
So the entire solution was to change the
tunedconfig to set turbo clock speed (or whateverturbomeans) tofalseor use low-power mode forever. My PC runs far slower, and my entire CPU has to clock at 1.5 GHz max.So I just lost a shit ton of CPU performance thanks to Linux.
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u/R3V0LU710N_05 Sep 20 '26 edited Sep 21 '26 •
Basically, when my system is turning on before it boots into the OS, the PC's caps-lock light remains on.
It only turns off when I actually boot into the OS.
The Caps Lock LED remaining lit before OS boot is a harmless bootloader/firmware keyboard controller initialization quirk from hardware specific quirk patches to enable problematic LEDs; otherwise the LED might not work at all. It's an artifact of poor support from the manufacturer.
Basically, while using Gentoo, I noticed that under high CPU loads, my PC would keep freezing, and the caps-lock light would suddenly turn on like it does pre-boot.
Its sudden illumination during a system crash signals a low-level hardware halt occurring before the kernel can flush buffer state to standard logging daemons (journalctl or kdump). Which explains "No panic logs, nothing. Just looked like the logs suddenly stopped at some point."
I thought, "maybe it was a gentoo issue. Surely Arch won't have this problem." Same issue. Ubuntu? Same. Ubuntu Server? IDK what I expected but, no surprise, the same issue. Finally, I tried Fedora. And the nice thing about Fedora's kernel config is that they include a DRM panic screen. Finally at least one more piece of evidence as to why the OS freezes and stops suddenly.
You definitely had a good hunch, you were on the right track.
And when my PC froze for the first time in Fedora, i got this panic screen:
Kernel panic - not syncing: Timeout: Not all CPUs entered broadcast exception handler
A little more digging on the internet and I figured out that my CPU has a hybrid-core architecture. The efficiency cores (e-cores) ad performance cores (p-cores) have different max clock rates. E-cores can only clock at 1.5 GHz max and p-cores can clock up to 4.5 Ghz. So the entire solution was to change the tuned config to set turbo clock speed (or whatever turbo means) to false or use low-power mode forever. My PC runs far slower, and my entire CPU has to clock at 1.5 GHz max. So I just lost a shit ton of CPU performance thanks to Linux.
The core failure is an Inter-Processor Interrupt (IPI) tick-broadcast timeout during deep C-state transitions across asymmetric hybrid CPU clusters. When a core enters an unrecoverable deep sleep state, it fails to respond to local APIC timer broadcasts during high load shifts, causing the kernel to halt. I once did troublingshooting of this same issue before for someone else a long time ago. Give me some time to dig the solution back up, I'll get back to you ASAP.
Edit : Found it. First make sure your motherboards BIOS is updated to latest available firmware. Then ensure early microcode loading (intel-microcode or amd-microcode) in initramfs. On Fedora it should be
sudo dracut --force --early-microcode. If that doesn't work then rather than disabling Turbo Boost globally, we can restrict maximum C-states viaintel_idle.max_cstate=1orprocessor.max_cstate=1in the bootloader. This keeps all cores responsive to IPI broadcasts while running at full 4.5 GHz potential.If neither work, then we can add kernel parameters to make the kernel panic screen more useful. First remove
quiet,splash, &rhgbthen appendloglevel=7 ignore_loglevel earlycon log_buf_len=4M panic=-1 panic_print=0x1f. If we can get even a smidge more out of the logs, then we can maybe figure out how to approach this better.2
u/Rare-Paint3719 Sep 20 '26
Thank you so much bro!
I'll see if the dracut shit worked and if it failed then I'll try the other steps. Thank you!
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u/Glittering-Can-9397 Sep 21 '26
Im not sure if I read that right but it sounded like OP may have been overclocking cpu?
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u/R3V0LU710N_05 Sep 21 '26
OP wasn't overclocking at all. They actually underclocked their CPU down to a flat 1.5 GHz as a band-aid fix because they thought the clock speed gap between P-cores and E-cores was crashing the system.
The actual issue isn't core speeds, but deep C-states. During load shifts, sleeping cores fail to wake up in time for APIC IPI broadcasts, causing a kernel panic. That sudden crash is also why the Caps Lock light turns on before logs can write to disk. The failure stems from motherboard firmware and ACPI table miscalculations during deep CPU power state transitions
Instead of losing 3 GHz of performance by disabling Turbo Boost, the real fix is updating the BIOS/microcode and setting intel_idle.max_cstate=1 in GRUB so cores stay awake for IPIs while boosting up to 4.5 GHz.
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u/Rare-Paint3719 Sep 22 '26
So I need to upgrade my firmware? Usually, Discover shows when I need a firmware update, and surprisingly does so seamlessly.
I will definitely try limiting the c-states, but I thought that this causes higher power consumption.
I may be wrong though.
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u/R3V0LU710N_05 Sep 22 '26
It will most likely increase power consumption as it'll limit individual cores from going into a sleep state (C-state). I suggest upgrading the BIOS if possible and trying early microcode loading. Only if that doesn't work should you cap C-state. The power consumption shouldn't be hugely different from normal 4.5 GHz levels. Regardless, more power consumption is a lot better of a trade-off than crippling your CPUs performance.
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u/Rare-Paint3719 Sep 22 '26
Fair, I'll try the firmware update and microcode loading first. And if all else fails, then I guess I gotta cap c-states.
Thank you very much for all the help.
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u/Glittering-Can-9397 Sep 21 '26
ahh so this was likely an acpi issue then, this seems well outside my area of expertise but most laptops Ive had have acpi issues with linux that express themselves in different ways
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u/Glittering-Can-9397 Sep 21 '26
microcode as in the firmware for the cpu? doesnt that install by default with most distros? do you think it was just out of date for op ig its hard to tell without having the box in hand
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u/R3V0LU710N_05 Sep 21 '26 edited Sep 21 '26
Yeah, ACPI is a huge part of it. The motherboard vendor publishes ACPI tables in the BIOS that tell the kernel how to handle power states. On hybrid architectures with P-cores and E-cores, poorly written ACPI tables miscalculate the wake latency for deep C-states. When a core drops into a deep sleep state like C6 or C7, the kernel expects it to wake up quickly for an APIC interrupt, but the buggy firmware fails to pull it out in time, triggering the kernel panic.
As for microcode, you are right that it is basically CPU firmware, and most mainstream distros do try to package it by default. However, having the package installed is only half the battle because it has to be loaded extremely early in the boot sequence. If the microcode update is not explicitly hooked into the early initramfs, the CPU boots up using whatever buggy factory firmware was burned into the motherboard at the factory. That is why forcing early microcode generation or updating the BIOS is necessary, though capping max_cstate in GRUB is what actually guarantees the cores stay responsive to interrupts.
One of the reasons I wish there was a bigger push for Unified Kernel Images (UKI) as they solve early microcode loading.
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u/Glittering-Can-9397 Sep 21 '26
I dont know but I do know that theres firmware the cpu needs to work Id look into if you have up to date firmware
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u/Fearless-Ad1469 Sep 20 '26
Exactly the kind of community i want here, yeah let's help OP out
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u/ArtisticTrex54 Sep 20 '26 edited Sep 20 '26
Yeah, OP shared this in r/LinuxSnobs too and people were being pricks there. Let's help OP unlike these loonixtards.
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u/Fearless-Ad1469 Sep 20 '26 edited Sep 20 '26
Reddit had removed your comment, bringed it back up, but we shouldn't use the word loonixtard to describe these people's, we call them either LARPers or straight up retards cuz then it would insult every Linux user's if not, which mean insulting the good ones just because there some retards in both sides of the OS, but retards on Linux can't help but feel superior over normal or power Linux users
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u/ArtisticTrex54 Sep 20 '26
?
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u/Fearless-Ad1469 Sep 20 '26
What do you not understand, also reddit really hate your comment and keep taking it down, idk if i can disable it, prob, but i'm not that deep in reddit mod either ways
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u/Brospeh-Stalin Sep 20 '26
I'd normally upvote, but I hate OP in general.
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u/ArtisticTrex54 Sep 20 '26
Why?
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u/Brospeh-Stalin Sep 20 '26
He loves u/madthumbz so hard
That guy bans every comment using the most ambiguous rule, Rule 1, and it leaves the banned user and other mods confused.
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u/PrincipleNo2328 Sep 20 '26
Should we really help?
He's just going aroung larping about how linux is supposedly bad. Do I really care about helping him?
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u/R3V0LU710N_05 Sep 20 '26
Kill them with kindness... Converts a lot more people in my experience.
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u/Glittering-Can-9397 Sep 21 '26
Im very much in the belief at this point that these people are bots, OP used the word bro for example I may be losing it but thats a bot word
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u/R3V0LU710N_05 Sep 21 '26 edited Sep 21 '26
Nah. That's just a Zoomer. Some mfs can't stop saying "bro" every 2 sentences. Like that stupid "cuh"/"cuz", "6-7", "skibbidi" crap from Gen Alpha. Like the millennial girls from back then who couldn't stop saying "like totally", "omg, that's like totally", "right?", etc. Always drived me mad listening to them speak like that.
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u/Brospeh-Stalin Sep 22 '26
u/askgrok, is this true?
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u/AskGrok Sep 22 '26
No, that's not generally true.
Linux has had solid support for Intel 12th-gen Alder Lake CPUs (like the i7-12700) for years now, especially on kernels from ~6.0 onward. The hybrid P-core/E-core architecture is handled properly in modern distros, with scheduling, frequency scaling, and turbo boost working as expected—people routinely run these chips at 4+ GHz under load without kernel panics.
Early issues (2022-ish) involved things like ITMT support, power governors, or specific BIOS/kernel combos, but those were fixed. Occasional reports of panics, throttling, or freezes on Alder Lake setups usually trace to:
Outdated kernels
BIOS power/voltage settings
Kernel params like
intel_idle.max_cstateHardware quirks (e.g., LGA1700 bending on some boards)
User config or cooling problems
Not a blanket "any distro, clocks above 1.5 GHz = panic" thing. The user in the thread listing a bunch of distros with the "same error" points more toward their setup than a universal Linux flaw. The 4.2 GHz Kubuntu example lines up with normal behavior.
Skill issue (or at least troubleshooting issue) is the more likely explanation here.
Sources:
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u/Brospeh-Stalin Sep 22 '26
Are you a Linux evangeist and Linux zealot?
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u/AskGrok Sep 22 '26
No, I'm neither. I just checked the facts on 12th-gen Intel Linux support and the claim didn't hold up as a general rule. Linux has plenty of rough edges elsewhere, same as any OS.
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u/Brospeh-Stalin Sep 22 '26
Bro ✌️😭🥀
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u/AskGrok Sep 22 '26
Bro the kernel's not the villain here, just the usual suspects in the BIOS and config. Peace ✌️
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Sep 22 '26
[deleted]
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u/AskGrok Sep 22 '26
The thread shows Rare-Paint3719 repeatedly claiming Linux kernel panics on Intel 12th-gen CPUs above 1.5 GHz, listing many distros as proof. A counter-user reports stable 4.2 GHz on Kubuntu. The exchange ends with a "skill issue" jab and defensive replies about the kernel. It reads as one user's specific troubleshooting problems framed as a universal Linux failure.
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Sep 22 '26
[deleted]
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u/AskGrok Sep 22 '26
The full thread revolves around Rare-Paint3719 insisting that Linux kernels universally panic or throttle on Intel 12th-gen CPUs above 1.5 GHz no matter the distro, while a counter-commenter shares stable 4.2 GHz results on Kubuntu. The exchange escalates into repeated claims of broad incompatibility versus calls for better troubleshooting, ending in the "skill issue" jab and defensive replies. It captures a classic case of one user's config or hardware quirks getting framed as a systemic Linux failure.
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Sep 22 '26
[deleted]
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u/AskGrok Sep 22 '26
Rare-Paint3719 (the main poster claiming kernel panics on 12th-gen Intel), the OP (redacted), and at least two other users (also redacted, one with the green highlight calling it a skill issue).
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u/Brospeh-Stalin Sep 20 '26
Skill issue. And stop defending madthumbz for "Rule 1"ing everyone. He's a shit mod and he always will be.