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Kernel panic shm

I have been following the guide on the looking glass page and where it says the following

when this is placed in the vm configuration upon starting the vm it causes an immediate kernel panic on the host and forces a reboot.

32? I think something went wrong with your post.

i have uploaded a screenshot of the section of code

The ivshmem device is part of QEMU, not Looking Glass, we just make use of it. It’s also a very simple/dumb device that just allocates some RAM for the VM, nothing more. What you describe points at something far more major wrong with your system as a whole.

but kvm and QEMU are part of redhat out of the box.

and?

and it is pre-configured. All i have done is followed the instructions outlined under red hat portal,

tested it found to be working then i attempted to set up looking glass. that section causes a kernel panic.

Again, this is not an issue with Looking Glass, but something with your PC, possibly bad RAM, motherboard, CPU, etc… IVSHMEM is a component of QEMU, not Looking Glass.

there is nothing wrong with the hardware. it is all brand new

where do i report the issue if not here?

Just because its new doesn’t mean anything. You may have overclocked the RAM too far, or the CPU, or you were unlucky and got some bad RAM or CPU, etc.

This is not an ivshmem/qemu bug, that feature of qemu is simply using a fundamental part of your kernel (shared memory) that many programs require. If simply adding the ivshmem device causes this fault, you have something more fundimental wrong with your PC.

At a bare minimum, you need to post the panic you’re getting and the hardware in your system before anyone can help you.

unfortunatly it is not dumping it to disk so unless there is some other way to retrieve it even this is not possible. as for hardware

i am running
AMD ryzon 5 3600
this is a hardware export
00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Root Complex
00:00.2 IOMMU: Advanced Micro Devices, Inc. [AMD] Starship/Matisse IOMMU
00:01.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
00:01.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge
00:02.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
00:03.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
00:03.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge
00:04.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
00:05.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
00:07.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
00:07.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B]
00:08.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge
00:08.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B]
00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 61)
00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 51)
00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 0
00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 1
00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 2
00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 3
00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 4
00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 5
00:18.6 Host bridge: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 6
00:18.7 Host bridge: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 7
01:00.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Matisse Switch Upstream
02:01.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Matisse PCIe GPP Bridge
02:02.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Matisse PCIe GPP Bridge
02:03.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Matisse PCIe GPP Bridge
02:04.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Matisse PCIe GPP Bridge
02:08.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Matisse PCIe GPP Bridge
02:09.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Matisse PCIe GPP Bridge
02:0a.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Matisse PCIe GPP Bridge
03:00.0 Non-Volatile memory controller: Kingston Technology Company, Inc. Device 500e (rev 01)
04:00.0 VGA compatible controller: NVIDIA Corporation GM206 [GeForce GTX 960] (rev a1)
04:00.1 Audio device: NVIDIA Corporation GM206 High Definition Audio Controller (rev a1)
05:00.0 PCI bridge: Creative Labs [SB X-Fi Xtreme Audio] CA0110-IBG PCIe to PCI Bridge
06:00.0 Audio device: Creative Labs CA0110 [Sound Blaster X-Fi Xtreme Audio]
07:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 16)
08:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Reserved SPP
08:00.1 USB controller: Advanced Micro Devices, Inc. [AMD] Matisse USB 3.0 Host Controller
08:00.3 USB controller: Advanced Micro Devices, Inc. [AMD] Matisse USB 3.0 Host Controller
09:00.0 SATA controller: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] (rev 51)
0a:00.0 SATA controller: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] (rev 51)
0b:00.0 VGA compatible controller: NVIDIA Corporation Device 2504 (rev a1)
0b:00.1 Audio device: NVIDIA Corporation Device 228e (rev a1)
0c:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Function
0d:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Reserved SPP
0d:00.1 Encryption controller: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Cryptographic Coprocessor PSPCPP
0d:00.3 USB controller: Advanced Micro Devices, Inc. [AMD] Matisse USB 3.0 Host Controller
0d:00.4 Audio device: Advanced Micro Devices, Inc. [AMD] Starship/Matisse HD Audio Controller

The Host gpu is an RTX3060

~Is the panic you’re getting on the host, or in the guest?~
Host, as per #1

What kernel versions are you using on the host? what version of qemu are you using on host?


There’s this:

/etc/sysctl.conf:

kernel.panic = 20

Which should cause a reboot after 20s, which should help you get a screenshot, e.g. using a phone before it reboots.

The stack shown should be helpful in figuring out what’s going on.

The panic is happening on the host (windows is on the Guest)
Kernel: Linux 4.18.0-305.3.1.el8_4.x86_64
QEMU emulator version 4.2.0 (qemu-kvm-4.2.0-48.module+el8.4.0+10368+630e803b)

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has anyone been successfull in getting this to work on redhat before? perhaps its just not compatible.

Barrybtec,

You are acting in ways that go against the purposes of the forum, which include having sensible discussions that actually achieve something. I recommend you try following what the users above asked of you and posting it accordingly. If you continue on acting the way you are, you WILL be seen as a help vampire and rightfully ignored.

Best regards,

vhns

I think @barrybtec is probably just out of their depth and eager to get something going.

To me, this smells like a bad kernel. Unfortunately it’s a 4.18 series which despite the patches is ancient. Qemu is a 4.2 which is also ancient.

I don’t use CentOS / RHEL, but my understanding is that if you’re paying red hat for support you’re stuck with whatever is the kernel that they ship.

I don’t know how hard it would be to boot RHEL off of something modern like whatever is the latest 5.10 release (that’s LTS and 6 months old - probably fairly stable).

Wow really. you are asking me to provide something my computer is not producing. When the kernel panics it flashes a wall of text off the screen in a very low resolution that can not get anything useful from it. everything else i have been asked i have provided

as for me being a help vampire i have been a member of this forum for less than a week so i really have had no chance to contribute. I was actually planing on documenting what was needed to get this working redhat after i get this working but when people give me attitude like that it makes me not want to participate.

I am on a paid subscription however it is self support , Redhat lag behind with kernel versions for stability however that is at the expense of comparability with newer software.

I also suspect that this may be related to the RTX 3060 card being so new it is not fully supported in the linux drivers provided by NVIDIA, and i am also on the NVIDIA-Linux-x86_64-460.84 driver as that seems to be the newest driver that work properly. ( newer drivers wont load the graphical interface) again this is a know issue with redhat 8. and even with that card not being the card i am passing through i suspect it is what may be causing the kernel panic.

@vhns and @barrybtec

Lets keep it cool guys thanks! :slight_smile:

Unfortunately i cannot really be helpfull with this issue.
But it might be usefull to also add info like which particular,
motherboard you are using.
You could of course also try a different distro.
But i’m kinda with @gnif at this point that it might be hardware,
or stability related probably.

No, you’re passing it through to the guest, the host kernel just has a stub that gives it to the guest, the host driver (nvidia) is not involved at all.

This is not the definition of a help vampire. The issue is more that you’re drip feeding informatoin to us about your issue forcing us to have to coach you through basic things. There is a reason the kernel panic contains lots of information… it’s for debugging/diagnostics. Doing some simple research would have yielded what you needed to capture this information so that you can provide it. A video recording of it would even be helpful if you can’t pause it, etc…

Without this information, it’s like going to a mechanic and asking him why your car which is still at home, doesn’t work, without providing any useful information such as make/model, noises, what you tried, etc.

The RTX3060 is being used by the nvidia drivers on the host. its the GTX960 that is being passed through to the guest os

It was about 4:30 am last night when i was discussing this. anyway after doing a reinstall of the nvidia drivers it does’t crash however it does chuck this error

Error starting domain: unsupported configuration: shmem model ‘ivshmem-plain’ is not supported by this QEMU binary

Traceback (most recent call last):
File “/usr/share/virt-manager/virtManager/asyncjob.py”, line 75, in cb_wrapper
callback(asyncjob, *args, **kwargs)
File “/usr/share/virt-manager/virtManager/asyncjob.py”, line 111, in tmpcb
callback(*args, **kwargs)
File “/usr/share/virt-manager/virtManager/object/libvirtobject.py”, line 66, in newfn
ret = fn(self, *args, **kwargs)
File “/usr/share/virt-manager/virtManager/object/domain.py”, line 1280, in startup
self._backend.create()
File “/usr/lib64/python3.6/site-packages/libvirt.py”, line 1234, in create
if ret == -1: raise libvirtError (‘virDomainCreate() failed’, dom=self)
libvirt.libvirtError: unsupported configuration: shmem model ‘ivshmem-plain’ is not supported by this QEMU binary

was support for this added after build of the version implemented in redhat?

Sorry i did put that in but i must have overwritten it when i pasted a pci export.

The motherboard is a Gigabite X570 Gaming

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