Fusion Mountain Lion bridging leads to kernel crash. How to submit bug report ?

[spyroot]

Hello Folks,

I've tried use bridging capability that comes in Mountain Lion kernel. 

It works fine with other virtual interfaces like tap but it trigger kernel crash if you bridge vmnet interface.

pretty simple POC

start fusion

sudo -s

ifconfig bridge0 create

ifconfig bridge0 up addm vmnet8

You can use any vmnet interface and it will immediately trigger kernel crash.  I've verified on couple of other computer

so it not computer specific.

Kind Regards,
Mustafa

[nancyz]

spyroot,

Why were you bridging to a virtual interface instead of a physical one?

[spyroot]

Hi LittleEyes

I want to bridge between one VM to another VM without using real physical interface.

The are couple of reason of that.

Reason number one.  Each my VM generate layer 2 BPDU and run STP protocol so if i bridge all BPDU to a signel physical interface

it create a huge problem. ( VLAN will not fix anything )

Reason two.   Each VM in my case require 3-4 virtual interface and I need to run 4 different VM

I just don't have sufficient USB port to simulate 15 physical ethernet port.

(As I said VLAN will not fix problem)

From a layer 2 perspective each pair of link between each VM need to be a pair of virtual point to point link.

so my idea

create tap0 and vmnet100 for VM 1  interface 1,  tap1 vmnet101 VM 1 interface 2 ... etc

so each VM and each virtual interface mapped to separate vmnet

Then I need simualate p2p connect between each pair

I can use two method and none of them actuall work explained before.

a.  Use Mountain kernel briding capability.  ( it there since BSD time)

b.  Use Native Fusion method vmnet-bridge

Kind Regards,
Mustafa

[nancyz]

Reason number one.  Each my VM generate layer 2 BPDU and run STP protocol so if i bridge all BPDU to a signel physical interface

Mustafa,

vmnet1 or vmnet8 are virtual interfaces,too. I'm not sure if we can bridge a physical interface to a virtual one.

[spyroot]

Well,

If I do

sudo -s

ifconfig bridge0 create

ifconfig bridge0 up addm tap0 tap1

It work pretty well. ( so qemu can do tun/tap)

if I do the same for vmnet it crashes kernel.

So something wrong with vmnet.

Kind Regards,
Mustafa

[changhai]

Mustafa,

I could reproduce this issue under my local envionment:kernel panic due to com.vmware.kext.vmnet module. I would engage with our developer to response you later and thanks a lot for your patience.

Interval Since Last Panic Report:  67224 sec
Panics Since Last Report:          1
Anonymous UUID:                    9B8C9259-B10B-43CE-8EB3-EC3DAD90713D

Mon Mar 25 21:59:38 2013
panic(cpu 0 caller 0xffffff7f8e74bd89): "vmnet: ASSERT bora/modules/vmnet/macos/netif.c:473
"@bora/modules/shared/macos/driverLog.c:190
Backtrace (CPU 0), Frame : Return Address
0xffffff8018eab6c0 : 0xffffff800ca1d5f6
0xffffff8018eab730 : 0xffffff7f8e74bd89
0xffffff8018eab890 : 0xffffff7f8e74bbf8
0xffffff8018eab8f0 : 0xffffff7f8e74fd5b
0xffffff8018eab910 : 0xffffff800cb3a53c
0xffffff8018eab970 : 0xffffff800cb35d76
0xffffff8018eab9b0 : 0xffffff800cb301f2
0xffffff8018eaba80 : 0xffffff800cb2fd28
0xffffff8018eabb90 : 0xffffff800cb3a53c
0xffffff8018eabbf0 : 0xffffff800cb3587c
0xffffff8018eabd60 : 0xffffff800cb35cc2
0xffffff8018eabd90 : 0xffffff800cd7c4c5
0xffffff8018eabdf0 : 0xffffff800cd7bf8b
0xffffff8018eabe20 : 0xffffff800cd4ae63
0xffffff8018eabe50 : 0xffffff800cd77a83
0xffffff8018eabf50 : 0xffffff800cde17da
0xffffff8018eabfb0 : 0xffffff800cacecf3
      Kernel Extensions in backtrace:
         com.vmware.kext.vmnet(106.8.27)[10260387-AA3B-3FBB-B218-447CADF3BE9A]@0xffffff7f8e74b000->0xffffff7f8e754fff

...

Best Regards,

changhai

[lewi99]

Hi Mustafa,

I was wondering if you ever had this resolved?   I am looking to do the same thing and get the panic as well

Thanks,

Andrew

[spyroot]

Nope mate.

As you see dev commented they are going to patch it.  So I hope 5.04 will have that patch.

[AzharSaleem]

Did some find a solution to bridge vmnet interface to tap in MAC without crash. I am seeing it every time i bridge vmnet to tap

thanks

[AzharSaleem]

Hi Mustafa,

Did you find any solution to bridge tap to vmnet without crash. I need some solution so GNS3 routers can talk to my virtual OS on mac?

I will appreciate help

thanks

Azhar

[spyroot]

Azhar,

I've posted about this issue and it present in 5.0.3. 

Meanwhile you can setup linux inside Fusion and use KVM and Openvswitch.

Kind Regards,
Mustafa

[changhai]

Mustafa/Azhar/Andrew,

This issue has been resolved in latest Fusion 6.0 build referring an internal ticket:1005484.

Thanks a lot for your patience and feedback for this issue.

Best Regards,

changhai

[AzharSaleem]

Hi Changhai,

When will be Fusion 6 available? Are there any betas?

thanks

Azhar

[ColoradoMarmot]

VMware Fusion Technology Preview 2013

[changhai]

Azhar,

>>When will be Fusion 6 available? Are there any betas?

As of now, Fusion 6.0 Tech Preview 1 is released as dlhotka mentioned; unfortunately, this fix is not included in the TP1 build.

Thanks a lot for your patience for new Fusion version.

Best Regards,

changhai

[changhai]

Azhar,

>>> bridging of vmnet and tap still not working in this beta, system crashes. That is very critical bug, need it fixed please.

From this thread, https://communities.vmware.com/docs/DOC-23363, you mentioned the issue is not got fixed.  we appreciate your feedback and please let us know the reproduced steps thanks a lot for your help.

if any misunderstanding, please correct me and thanks!

Best Regards,

changhai