Dom0 losing interrupts???

[Juergen Gross <juergen.gross@ts.fujitsu.com>]

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?


Juergen

-- 
Juergen Gross                 Principal Developer Operating Systems
TSP ES&S SWE OS6                       Telephone: +49 (0) 89 3222 2967
Fujitsu Technology Solutions              e-mail: juergen.gross@ts.fujitsu.com
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