[SOLVED] IBT Support (default since kernel 6.2)

Discussions related to using VirtualBox on Linux hosts.
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

[SOLVED] IBT Support (default since kernel 6.2)

Post by marmel »

I chimed in on Ticket #21435
https://www.virtualbox.org/ticket/21435

... with the same comment/question as below. Seems these forums are more actively supported than the bug tracker, as there's zero developer response to the many of the tickets I follow since Vbox 7.x was released:
viewtopic.php?f=7&t=108440&p=532943

After having waited nearly a year since the kernel 5.18 release introduced IBT (May 2022), for nVidia to get their act together and support IBT in their proprietary modules (530.41.03 finally!), I now come to realize that the latest Virtualbox 7.0.6 fails with IBT enabled.

This has been the default config as of kernel 6.2.x. Currently running 6.2.7 here.

Workaround: Add ibt=off kernel parameter
Attachments
vbox-fail-ibt-kernel.log
(4.86 KiB) Downloaded 26 times
vbox-fail-ibt.log
(1.94 KiB) Downloaded 18 times
Last edited by marmel on 21. Jul 2023, 17:31, edited 3 times in total.
scottgus1
Site Moderator
Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: IBT Support (default since kernel 6.2)

Post by scottgus1 »

No ideas about the IBT thing here, but on this:
marmel wrote:there's zero developer response to the many of the tickets I follow since Vbox 7.x was released:
This is common, The devs often go off to fix the bugs based on the data without necessarily posting back on the tickets. And 7.0 is a big dev push just now. Some of the tickets are specific requests to get data to figure out the graphics bugs in 7.0.
scottgus1
Site Moderator
Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: IBT Support (default since kernel 6.2)

Post by scottgus1 »

As a possible workaround, your link to the Arch wiki here viewtopic.php?f=7&t=108892&p=534175#p534173 says:
you can try adding ibt=off as a kernel parameter.
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

scottgus1 wrote:As a possible workaround, your link to the Arch wiki here viewtopic.php?f=7&t=108892&p=534175#p534173 says:
you can try adding ibt=off as a kernel parameter.
I think you may have replied to the wrong thread, but thanks. I provided that link to the workaround here for another user:
viewtopic.php?f=7&t=108892#p534173

EDIT: Perhaps it wasn't clear (only implied) from my OP that those of us using the nVidia proprietary driver have been applying the ibt=off kernel parameter for about a year now, until the recently released nVidia driver arrived, which was compiled with support for IBT.
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

Virtualbox 7.0.8 also fails to launch with IBT enabled (the default kernel config).

System journal errors are consistent with kernel modules being built without support for Indirect Branch Tracking.

Code: Select all

May 20 08:50:12 kernel: traps: Missing ENDBR: 0xffffa99507f4a430
May 20 08:50:12 kernel: kernel BUG at arch/x86/kernel/traps.c:255!
May 20 08:50:12 kernel: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
This has been the default kernel config on Arch Linux for 14 months now, and will soon be the default in Debian, Ubuntu, etc.

Bug ticket updated thusly:
https://www.virtualbox.org/ticket/21435
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

Linking another forum thread where lack of IBT support in recent Virtualbox releases (7.0.8 at time of post) turned out to be the culprit:
Looks like Fedora users are starting to hit this issue now as well.
Last edited by marmel on 6. Jun 2023, 14:02, edited 1 time in total.
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

And another thread on this issue (Fedora):
Workaround: Add ibt=off kernel parameter
Last edited by marmel on 13. Jun 2023, 15:49, edited 2 times in total.
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

Yet another thread, same issue (openSUSE):
Workaround: Add ibt=off kernel parameter
Last edited by marmel on 13. Jun 2023, 15:49, edited 1 time in total.
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

Mods: Perhaps consider pinning this thread until VB supports compiling kernel modules with IBT support?

@scottgus1
@mpack
scottgus1
Site Moderator
Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: IBT Support (default since kernel 6.2)

Post by scottgus1 »

@Marmel, I asked our forum Linux gurus to investigate the possibility of an IBT sticky, we'll see what we can do!
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

scottgus1 wrote: 12. Jun 2023, 13:53 @Marmel, I asked our forum Linux gurus to investigate the possibility of an IBT sticky, we'll see what we can do!
Great, thanks! I think it might be helpful.

We Arch folks went through this last year when the IBT switch was toggled on in the kernel config. There were many, many threads all with the same solution. nVidia driver users (myself included) could not boot to a graphical desktop with IBT enabled.
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

Linking another new Fedora thread where IBT was the issue:
Workaround: Add ibt=off kernel parameter
marmel
Posts: 75
Joined: 1. Nov 2013, 03:44

Re: IBT Support (default since kernel 6.2)

Post by marmel »

Another new openSUSE Tumbleweed thread where IBT was the issue:
Workaround: Add ibt=off kernel parameter
scottgus1
Site Moderator
Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: IBT Support (default since kernel 6.2)

Post by scottgus1 »

Marmel, would you happen to know how to test if a Linux host has IBT enabled, and what command & output a user might see?

I have a sticky ready to go but I need that info to complete it.
fth0
Volunteer
Posts: 5668
Joined: 14. Feb 2019, 03:06
Primary OS: Mac OS X other
VBox Version: PUEL
Guest OSses: Linux, Windows 10, ...
Location: Germany

Re: IBT Support (default since kernel 6.2)

Post by fth0 »

The following command inside a Linux terminal could give the following output if IBT is supported by the running Linux kernel (at least on Debian Linux / Ubuntu Linux / Linux Mint):

Code: Select all

grep X86_KERNEL_IBT /boot/config-$(uname -r)
CONFIG_X86_KERNEL_IBT=y
Post Reply