Re: [Openipmi-developer] BUG: soft lockup detected on CPU#1, ipmi_si

[Corey Minyard <minyard@acm.org>]

Peter, can you make a code change for me and try something out?

If possible, could you change the call to udelay(1) in the function
ipmi_thread() in drivers/char/ipmi_si_intf.c to be a call to schedule()
instead?  I'm guessing that will fix this problem.

-Corey

Peter Palfrader wrote:
> On Sun, 18 Jun 2006, Corey Minyard wrote:
>
>   
>> The IPMI driver spawns a low-priority thread that will poll the driver
>> when it finds there is something to do.  It's possible that the hardware
>> is not setting things properly and is always telling the driver it has
>> to do something.  It's possible that the new version of the firmware
>> enabled interrupts; I think there's a problem with the driver here; it
>> should not really enable the kernel thread if interrupts are working. 
>> The driver should also probably call schedule() instead of udelay() in
>> the kernel thread when a short timeout is requested by the state machine.
>>
>> In either situation, the kernel thread will sit there and spin, and if
>> nothing else is scheduled for 10 seconds on that CPU you will get that
>> warning.  Can you check a few things for me?
>>
>> cat /proc/ipmi/0/si_stats and send me the output.
>>     
>
> After running for about 35 minutes (and one instance of the soft lockup
> warning):
>
> | interrupts_enabled:    0
> | short_timeouts:        8835
> | long_timeouts:         263709
> | timeout_restarts:      0
> | idles:                 793108
> | interrupts:            0
> | attentions:            0
> | flag_fetches:          2137
> | hosed_count:           0
> | complete_transactions: 3516
> | events:                0
> | watchdog_pretimeouts:  0
> | incoming_messages:     0
>
>
>   
>> If you do "top", is the kipmi0 always running?
>>     
>
> Yes, running since the system started around 11:00:
>
> | root      1331  0.8  0.0     0    0 ?        SN   10:59   0:17  \_ [kipmi0]
>
>   
>> Is your IPMI interface KCS or SMIC?  The IPMI driver should report this
>> in the system log at startup.
>>     
>
> It's KCS:
>
> | laura:~# dmesg  | grep -i ipmi
> | [   85.110244] ipmi message handler version 39.0
> | [   85.111491] ipmi device interface
> | [   85.127866] IPMI System Interface driver.
> | [   85.127929] ipmi_si: Trying SMBIOS-specified KCS state machine at I/O address 0xca2, slave address 0x20, irq 0
> | [   85.274699] ipmi: Found new BMC (man_id: 0x000f85,  prod_id: 0x0000, dev_id: 0x00)
> | [   85.274852]  IPMI KCS interface initialized
> | [   85.284710] IPMI Watchdog: driver initialized
>
> Cheers,
> Peter
>