Re: credit2 BUG_ON triggered

[John Weekes <lists.xen@nuclearfallout.net>]

On 4/20/2011 9:51 AM, George Dunlap wrote:
> Yes, please, if you have the time.  xen-unstable has some debugging
> output I put there after this failure was seen once in the xen.org
> automated testing.  I've been over that code a number of times, and have
> no idea how that bug could be triggering. :-)
>
> Alternately, if you find unstable too unstable (or if you don't want to
> find out), you can revert xen-4.1-testing c/s 22977:6af8e01d3e4a, which
> turns off the debugging code I'd put in for the 4.1 release.

Any version works for me, since this is just for testing purposes (this 
isn't a production machine yet).

On xen-unstable, I'm seeing that the domU just hangs after it starts. 
The stubdom chews CPU very slowly, but there is no activity on the main 
domain:

dallas-dodec226-5 customers # xl list
Name                                        ID   Mem VCPUs      State   
Time(s)
Domain-0                                     0  1500     4     r-----    
4061.2
testvds4                                     3   803     1     
-b----       0.0
testvds4-dm                                  4    32     1     
-b----       0.6

It's hanging after this:

(XEN) irq.c:258: Dom3 PCI link 1 changed 0 -> 10
(XEN) HVM3: PCI-ISA link 1 routed to IRQ10
(XEN) irq.c:258: Dom3 PCI link 2 changed 0 -> 11
(XEN) HVM3: PCI-ISA link 2 routed to IRQ11
(XEN) irq.c:258: Dom3 PCI link 3 changed 0 -> 5
(XEN) HVM3: PCI-ISA link 3 routed to IRQ5
(XEN) HVM3: pci dev 01:2 INTD->IRQ5
(XEN) HVM3: pci dev 01:3 INTA->IRQ10
(XEN) HVM3: pci dev 03:0 INTA->IRQ5
(XEN) HVM3: pci dev 04:0 INTA->IRQ5
(XEN) HVM3: pci dev 02:0 bar 10 size 02000000: f0000008
(XEN) HVM3: pci dev 03:0 bar 14 size 01000000: f2000008
(XEN) HVM3: pci dev 04:0 bar 10 size 00020000: f3000000
(XEN) HVM3: pci dev 02:0 bar 14 size 00001000: f3020000
(XEN) HVM3: pci dev 03:0 bar 10 size 00000100: 0000c001
(XEN) HVM3: pci dev 04:0 bar 14 size 00000040: 0000c101
(XEN) HVM3: pci dev 01:2 bar 20 size 00000020: 0000c141
(XEN) HVM3: pci dev 01:1 bar 20 size 00000010: 0000c161
(XEN) HVM3: Multiprocessor initialisation:
(XEN) HVM3:  - CPU0 ... 40-bit phys ... fixed MTRRs ... var MTRRs [2/8] 
... done.
(XEN) HVM3:  - CPU1 ... 40-bit phys ... fixed MTRRs ... var MTRRs [2/8] 
... done.
(XEN) HVM3:  - CPU2 ... 40-bit phys ... fixed MTRRs ... var MTRRs [2/8] 
... done.
(XEN) HVM3:  - CPU3 ... 40-bit phys ... fixed MTRRs ... var MTRRs [2/8] 
... done.
(XEN) HVM3: Testing HVM environment:
(XEN) HVM3:  - REP INSB across page boundaries ... passed
(XEN) HVM3:  - GS base MSRs and SWAPGS ... passed
(XEN) HVM3: Passed 2 of 2 tests
(XEN) HVM3: Writing SMBIOS tables ...

Killing the domU works properly.

I'll try 4.1-testing again with the patch reversion.

-John