Subject: Re: [PATCH] tproxy: nf_tproxy_assign_sock() can handle tw sockets

From: Avi Kivity <[email-masked]>
Date: Sun, 11 Jul 2010 08:19:21 +0300

On 07/10/2010 09:17 AM, Eric Dumazet wrote:
>
> Strange thing with your crash report is CR2 value, with unexpected value
> of 000000000b388000 while RAX value is dce8dce85d415d41
>
> Faulting instruction is :
>
> 48 83 b8 b0 00 00 00 00   cmpq   $0x0,0xb0(%rax)
>
> So I would have expected CR2 being RAX+0xb0, but its not.
>    

Nothing strange about it.  You only get page faults and valid cr2 for 
canonical addresses (17 high order bits all equal).  In this case 
rax+0xb0 is not a canonical address, so you got a general protection 
fault instead, with cr2 unchanged.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.