Re: Dom0 losing interrupts???

["André Przywara" <andre.przywara@amd.com>]

Am 14.02.2011 07:59, schrieb Juergen Gross:
> Hi,
>
> while trying to reproduce Andre's cpupool problem I ran into another issue:
>
> Dom0 seems to lose hardware interrupts when it has more vcpus than pcpus
> available. First I thought this could be due to my cpupool patches, but the
> problem can be easily reproduced by pinning all Dom0 vcpus to a few physical
> cpus and doing a parallel build then.
>
> I used xen-unstable, kernel 2.6.32.24 from SLES11 SP1 on a 12 core INTEL
> nehalem machine. I pinned all 12 Dom0 vcpus to pcpu 1-2 and started a parallel
> build. After about 2 minutes the first missing interrupts were reported, a
> little bit later the next one, no xen messages are printed:
>
> [230644.814834] ata1: lost interrupt (Status 0x50)
> [230682.814399] ata1: lost interrupt (Status 0x50)
> [230690.814467] ata1: lost interrupt (Status 0x58)
> ...
> [230856.718437] sd 4:2:0:0: [sda] megasas: RESET -843713 cmd=2a retries=0
> [230856.739457] megaraid_sas: HBA reset handler invoked without an internal
> reset condition.
> [230856.766435] megasas: [ 0]waiting for 16 commands to complete
>
> Has anyone observed a similar behavior?

Yes, me again:-)

On the rare occasions where I couldn't trigger the bug (like when using 
a restricted Dom0) I observed interrupt problems, which mostly killed 
the network connection:
(XEN) do_IRQ: 0.89 No irq handler for vector (irq -1)
I could solve this issue temporarily be down-ing and up-ing the network 
interface, but the box became unstable later.
hypervisor and tools c/s 22858, Dom0 latest tip of PVOPS 
xen/stable-2.6.32.x (2.6.32.27)

Regards,
Andre.