Re: gdbsx - xg_attach:Unable to pause domain:1; failed to attach to domain:1 errno:13

[Mukesh Rathor <mukesh.rathor@oracle.com>]

On Wed, 27 Aug 2014 03:02:54 +0000
Pete Delaney <pdelaney@silver-peak.com> wrote:

> Hi Mukesh:
> 
>     > Hmm... I just tried and it worked for me, so things are ok it
>     > seems on latest xen/linux. The errno EPERM indicates something
>     > might not be properly setup. Are you able to run other xen
>     > commands like xl list, etc? I see you are running as root, are
>     > you running gdbsx on dom0? 
>  
> Gdbsx runs on dom0, which I believe is the same as running on the
> host when it's booting for Xen support in the grub selection. On the
> host the Xen commands are available as I showed in my initial email,
> I used the "xl list" and "xl pause" commands:
> 
>     >  root@piet-openxen:~# xl list
>     > 	Name                                        ID   Mem
>     > VCPUs  State   Time(s)
>     >	 Domain-0                                     0 14734
>     >	12     r-----    8562.9
>     >	New_PV_Driver                                1  1023
>     >	4     -b----      50.3
>    >  root@piet-openxen:~#
> 
>     > root@piet-openxen-blade:~# xl pause 1
> 
> 
> I was running as root on the host/dom0.

Hmm... that all seems ok then. Can you check your permissions on :

/proc/xen/privcmd


Other possibilites:
  - do you have xsm enabled?

  - can you put a printk in xen file common/domctl.c:

    case XEN_DOMCTL_pausedomain:
        ret = -EINVAL;
+       printk(">>>>>>>>> Pause domain:%d current:%d\n", d->domain_id, 
+              current->domain->domain_id);
        if ( d != current->domain )
            ret = domain_pause_by_systemcontroller(d);
        break;

if you don't see this printk then the problem is in dom0 linux, prob
some permissions either on the privcmd file or somewhere in FS path.

> Wondering if the host kernel has to be configured to support gdb
> attaching with gdbsx.

Nop, at this point you are just not able to establish connection with
xen. gdb is not involved.

-Mukesh