Re: [Xen-devel] Re: [Xen-users] 2.6.23 oops

Morten Bøgeskov
Thu, 11 Oct 2007 18:22:30 -0000

Quoting Mark Williamson <mark.williamson@cl.cam.ac.uk>:

>> >   I''ve tried to run 2.6.23 on xen 3.1.0, my hardware is a
Dual Athlon MP.
>> > my DomU is running 2.6.23 SMP (vcpus = 1), without SMP it hang
during
>> > boot, with it panics. I''ve attached my config, if
somebody thinks I''ve
>> > left something out
>>
>> Do you mean that it hangs during boot if SMP is not compiled into the
guest
>> kernel?  That seems strange, I''ll try that out myself and see
what happens.
>
> Where does it hang for you?
>
> I disabled SMP in my kernel config and found that the guest hung during the
> kernel messages, just after:
>
> 	installing Xen timer for CPU 0
>
> Is this similar to what you observed?



That is exactly what I experienced. I tracked it down to:

xen_vcpuop_set_next_event(...)
  ret = HYPERVISOR_vcpu_op(VCPUOP_set_singleshot_timer, cpu, &single);

always returns -ETIME
resulting in a infinite loop in
tick_setup_periodic(...)
Where this never succeeds
      if (!clockevents_program_event(dev, next, ktime_get()))
                                 return;


Now my brain needs a rest. I never thought I had to go head first into
the linux-kernel ;-) can''t claim that I got any wiser ;-)


>
> Cheers,
> Mark
>
>> How far into the boot does it manage to get?  Has it started running
>> userspace apps (the normal startup messages starting essential
services),
>> or is it still during the kernel initialisation?
>>
>> > Does anybody else see this:
>>
>> I''ve booted a kernel successfully on a UP AMD64 box with an
SMP 2.6.23
>> kernel, vcpus = 1 but I didn''t bother giving it a virtual
disk, so I don''t
>> know if userspace worked.  I''ll give it a try shortly...
>>
>> Cheers,
>> Mark
>>
>> > ------------[ cut here ]------------
>> > kernel BUG at arch/i386/xen/multicalls.c:68!
>> > invalid opcode: 0000 [#1]
>> > SMP
>> > CPU:    0
>> > EIP:    0061:[<c01019a6>]    Not tainted VLI
>> > EFLAGS: 00010002   (2.6.23 #26)
>> > EIP is at xen_mc_flush+0xa6/0xb0
>> > eax: 00000001   ebx: 00000003   ecx: 00000001   edx: c10c1060
>> > esi: 00000000   edi: 00000001   ebp: c5c8d000   esp: c1101d28
>> > ds: 007b   es: 007b   fs: 00d8  gs: 0000  ss: e021
>> > Process swapper (pid: 1, ti=c1100000 task=c10eda90
task.ti=c1100000)
>> > Stack: 000218ee c10c10a0 c10c1460 c0101ede c5c8ce40 c02b90e0
c10eda90
>> > 00000000 c0101ff3 c5c8ce40 c015caca c5d3b49c 00000080 c5eadaa0
00000000
>> > c10eed80 c01584d0 c02b9a80 c5cfd560 c02a53d2 c1142440 c015c077
c1101d84
>> > c5eadaa0 Call Trace:
>> >   [<c0101ede>] xen_pgd_pin+0x9e/0x100
>> >   [<c0101ff3>] xen_activate_mm+0x13/0x20
>> >   [<c015caca>] flush_old_exec+0x3ca/0x7f0
>> >   [<c01584d0>] do_sync_read+0x0/0x120
>> >   [<c015c077>] kernel_read+0x37/0x50
>> >   [<c018308e>] load_elf_binary+0x2fe/0x1af0
>> >   [<c013ec27>] __alloc_pages+0x57/0x310
>> >   [<c0155387>] kmem_cache_alloc+0x47/0x90
>> >   [<c0147610>] handle_mm_fault+0x540/0x710
>> >   [<c01585a5>] do_sync_read+0xd5/0x120
>> >   [<c0145e10>] vm_normal_page+0x10/0x70
>> >   [<c0145e10>] vm_normal_page+0x10/0x70
>> >   [<c0146471>] follow_page+0xf1/0x170
>> >   [<c01478ca>] get_user_pages+0xea/0x2e0
>> >   [<c015bbe2>] get_arg_page+0x42/0xa0
>> >   [<c015bdc6>] copy_strings+0x186/0x1a0
>> >   [<c015be64>] search_binary_handler+0x54/0x110
>> >   [<c015d83b>] do_execve+0x14b/0x170
>> >   [<c010425f>] sys_execve+0x2f/0x90
>> >   [<c0105c72>] syscall_call+0x7/0xb
>> >   [<c010a364>] kernel_execve+0x14/0x20
>> >   [<c0100173>] init_post+0xa3/0xf0
>> >   [<c02d594f>] kernel_init+0x20f/0x310
>> >   [<c0118464>] schedule_tail+0x34/0x90
>> >   [<c0105b16>] ret_from_fork+0x6/0x20
>> >   [<c0105c7b>] syscall_exit+0x5/0x1b
>> >   [<c02d5740>] kernel_init+0x0/0x310
>> >   [<c02d5740>] kernel_init+0x0/0x310
>> >   [<c0106e77>] kernel_thread_helper+0x7/0x10
>> >   ======================>
>
>
> --
> Dave: Just a question. What use is a unicyle with no seat?  And no pedals!
> Mark: To answer a question with a question: What use is a skateboard?
> Dave: Skateboards have wheels.
> Mark: My wheel has a wheel!