[Freeipmi-devel] lib: raw command and threads

[Thomas Cadeau]

Hi all,


I'am curently tring to call a raw command several times.
Here are the functions I call:

> ctx = ipmi_ctx_create()
>
> ipmi_ctx_find_inband (ctx,
>                   NULL,//&driver_type,
>                   0,   // disable_auto_probe,
>                   0,   // driver_address,
>                   0,   // register_spacing,
>                   0,   // driver_device,
>                   0,   // workaround_flags,
>                   IPMI_FLAGS_DEFAULT//0
>                   )
>
> ipmi_cmd_raw(ctx,
>              0x00, //lun (logical unit number)
>              0x3A,//IPMI_NET_FN_SENSOR_EVENT_RQ,
>              bytes_rq, //request data //const void *
>              2, //length (in bytes)
>              bytes_rs, //response buffer //void *
>              IPMI_RAW_MAX_ARGS //max response length
>              )
I check all return code.

If I create a simple example with a loop, I have no problem.
> ctx = ipmi_ctx_create()
> ipmi_ctx_find_inband ( ...  )
> for (...){
> ipmi_cmd_raw(...)
> //use result
> }

Then I try inside an internal project, during initialization, I use the 
3 functions, and then each time I want to update and call 
ipmi_cmd_raw(...), a thread is created to do all operations.

> ctx = ipmi_ctx_create()
> ipmi_ctx_find_inband ( ...  )
>  ipmi_cmd_raw(...)
>  //use result
> ...
> //with fixed frequency:
> launch thread
>        > ipmi_cmd_raw(...)
>        > //use result
In this case, on some cpus, I have no problem. But on some, I have a 
segfault (core dump):
> #0  0x00007f4e278c89a9 in inb (ctx=0x7f4e28001770) at 
> /usr/include/sys/io.h:48
> #1  _ipmi_kcs_get_status (ctx=0x7f4e28001770) at 
> driver/ipmi-kcs-driver.c:533
> #2  0x00007f4e278c8e50 in _ipmi_kcs_wait_for_ibf_clear 
> (ctx=0x7f4e28001770)
>     at driver/ipmi-kcs-driver.c:656
> #3  0x00007f4e278c91d6 in ipmi_kcs_write (ctx=0x7f4e28001770, 
> buf=0x7f4e28003420, buf_len=3)
>     at driver/ipmi-kcs-driver.c:845
> #4  0x00007f4e27898bc1 in _kcs_cmd_write (ctx=0x7f4e28005190, 
> obj_cmd_rq=<value optimized out>,
>     obj_cmd_rs=0x7f4e28001ae0) at api/ipmi-kcs-driver-api.c:255
> #5  api_kcs_cmd (ctx=0x7f4e28005190, obj_cmd_rq=<value optimized out>, 
> obj_cmd_rs=0x7f4e28001ae0)
>     at api/ipmi-kcs-driver-api.c:398
> #6  0x00007f4e27899091 in api_kcs_cmd_raw (ctx=0x7f4e28005190, 
> buf_rq=0x7f4e2e390a60, buf_rq_len=2,
>     buf_rs=0x7f4e2e38f8c0, buf_rs_len=4512) at 
> api/ipmi-kcs-driver-api.c:750
> #7  0x00007f4e2788f9a9 in ipmi_cmd_raw (ctx=0x7f4e28005190, lun=<value 
> optimized out>,
>     net_fn=<value optimized out>, buf_rq=0x7f4e2e390a60, buf_rq_len=2, 
> buf_rs=0x7f4e2e38f8c0,
>     buf_rs_len=4512) at api/ipmi-api.c:1983
If I force to connect again, I have no problem. But this workaround is 
not a good way:
> ctx = ipmi_ctx_create()
> ipmi_ctx_find_inband ( ...  )
>  ipmi_cmd_raw(...)
>  //use result
> ...
> //with fixed frequency:
> launch thread
>        > ipmi_ctx_close(ctx)
>        > ipmi_ctx_destroy(ctx);
> > ctx = ipmi_ctx_create()
> > ipmi_ctx_find_inband ( ...  )
>        >ipmi_cmd_raw(...)
>        > //use result
Note that I check the version of BMC on each nodes, and I use 
freeipmi-1.2.1.
I also hace security to ensure only one use of ctx can be done.

Do you have any idea of what happpens and if I'm doing something wrong?
Is there a function to check the connection is opened and if I need to 
reopen?

Thank you for your help.

Thomas Cadeau