Re: Re: 2.6.28.7 domU: 32-bit emulation seems to be broken

[Jeremy Fitzhardinge <jeremy@goop.org>]

Sven Köhler wrote:
> Jeremy Fitzhardinge schrieb:
>   
>> Sven Köhler wrote:
>>     
>>> Jeremy Fitzhardinge schrieb:
>>>       
>>>> Jeremy Fitzhardinge wrote:
>>>>         
>>>>> Do you have auditing enabled?
>>>>>           
>>>> (No)
>>>>         
>>> You answered yourself, right?
>>> (yes, CONFIG_AUDIT is disabled)
>>>
>>> Can I supply you with any further information?
>>>       
>> I need to find/set up an AMD system to try to repro it I think.  I think
>> the problem is actually the return from the syscall, rather than the
>> syscall entry itself.  What happens if you run the program under either
>> strace or gdb?
>>     
>
> The program just works:
>
> # strace ./a.out
> execve("./a.out", ["./a.out"], [/* 24 vars */]) = 0
> [ Process PID=8968 runs in 32 bit mode. ]
> uname({sys="Linux", node="xen-to1", ...}) = 0
> brk(0)                                  = 0x80c3000
> brk(0x80c3cb0)                          = 0x80c3cb0
> set_thread_area(0xffa5182c)             = 0
> brk(0x80e4cb0)                          = 0x80e4cb0
> brk(0x80e5000)                          = 0x80e5000
> fstat64(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 0), ...}) = 0
> mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1,
> 0) = 0xfffffffff7f51000
> write(1, "Hallo Welt!\n"..., 12Hallo Welt!
> )        = 12
> exit_group(0)                           = ?
>   

OK, that confirms that its sysret32 that's failing.  vdso32=0 on the 
kernel command line should be the workaround until we've got a proper fix.

    J