Re: netif_suspend / resume

[Jacob Gorm Hansen <jacobg@diku.dk>]

Ian Pratt wrote:

> The guest keeps its own shadow copy of the state as regards which pfn's
> it has queued as {free, rx, tx}bufs. After a resume it 'gathers' those
> pages and requeues the free and tx bufs to the new backend. 
> 
> We currently junk any outstanding rxbufs, but in reality there almost
> never are any as the vif interrupt will be serviced before the suspend
> thread gets to run. When we switch over to grant tables we'll be able to
> process these on the destination too, as we'll know the memory has been
> syncronized. It won't make difference, though.

With the latest unstable, I am trying to do this:

     __cli();

     netif_suspend();
     time_suspend();
     ctrl_if_suspend();
     irq_suspend();


     irq_resume();
     ctrl_if_resume();
     time_resume();
     netif_resume();


     __sti();

(The domU has no blockdev support compiled in).

But I immediately crash trying to reference 0x050d4286 in 
network_tx_buf_gc(), at the last instruction in the disasm below:

c0222e20 <network_tx_buf_gc>:
c0222e20:   55                      push   %ebp
c0222e21:   57                      push   %edi
c0222e22:   56                      push   %esi
c0222e23:   53                      push   %ebx
c0222e24:   83 ec 04                sub    $0x4,%esp
c0222e27:   8b 44 24 18             mov    0x18(%esp),%eax
c0222e2b:   89 04 24                mov    %eax,(%esp)
c0222e2e:   89 c6                   mov    %eax,%esi
c0222e30:   81 c6 20 02 00 00       add    $0x220,%esi
c0222e36:   83 be 88 00 00 00 02    cmpl   $0x2,0x88(%esi)
c0222e3d:   74 06                   je     c0222e45 <network_tx_buf_gc+0x25>
c0222e3f:   58                      pop    %eax
c0222e40:   5b                      pop    %ebx
c0222e41:   5e                      pop    %esi
c0222e42:   5f                      pop    %edi
c0222e43:   5d                      pop    %ebp
c0222e44:   c3                      ret
c0222e45:   8b 56 74                mov    0x74(%esi),%edx
c0222e48:   90                      nop
c0222e49:   8d b4 26 00 00 00 00    lea    0x0(%esi),%esi
c0222e50:   8b 7a 08                mov    0x8(%edx),%edi
c0222e53:   f0 83 44 24 00 00       lock addl $0x0,0x0(%esp)
c0222e59:   8b 5e 6c                mov    0x6c(%esi),%ebx
c0222e5c:   39 fb                   cmp    %edi,%ebx
c0222e5e:   74 42                   je     c0222ea2 <network_tx_buf_gc+0x82>
c0222e60:   0f b6 c3                movzbl %bl,%eax
c0222e63:   8b 6e 74                mov    0x74(%esi),%ebp
c0222e66:   8d 04 40                lea    (%eax,%eax,2),%eax
c0222e69:   c1 e0 02                shl    $0x2,%eax
c0222e6c:   8b 96 a8 00 00 00       mov    0xa8(%esi),%edx
c0222e72:   01 e8                   add    %ebp,%eax
c0222e74:   0f b7 40 10             movzwl 0x10(%eax),%eax
c0222e78:   8b 8c 86 a8 00 00 00    mov    0xa8(%esi,%eax,4),%ecx
c0222e7f:   89 94 86 a8 00 00 00    mov    %edx,0xa8(%esi,%eax,4)
c0222e86:   89 86 a8 00 00 00       mov    %eax,0xa8(%esi)
c0222e8c:   ff 89 84 00 00 00       decl   0x84(%ecx)
                                            ^^^^^^^^^^
Any hints for debugging this?

thanks,
Jacob