Re: [uml-devel] fuzz tested 32 bit user mode linux image hangs in radix_tree_next_chunk()

[Richard Weinberger <richard@nod.at>]

Am 09.11.2013 20:07, schrieb Toralf Förster:
> On 11/06/2013 10:31 PM, Richard Weinberger wrote:
>> Am 06.11.2013 22:18, schrieb Toralf Förster:
>>> On 11/06/2013 05:06 PM, Konstantin Khlebnikov wrote:
>>>> In this case it must stop after scanning whole tree in line:
>>>> /* Overflow after ~0UL */
>>>> if (!index)
>>>>   return NULL;
>>>>
>>>
>>> A fresh current example with latest git tree shows that lines 769 and 770 do alternate :
>>
>> Can you please ask gdb for the value of offset?
>>
>> Thanks,
>> //richard
>>
> 
> Still trying to get those values. One attempt to do that was to replace -O2 with -O0 in the Makefile,
> but that resulted into this error :
> 
>   LD      kernel/built-in.o
>   CC      mm/memory.o
> In function ‘zap_pmd_range’,
>     inlined from ‘zap_pud_range’ at mm/memory.c:1265:8,
>     inlined from ‘unmap_page_range’ at mm/memory.c:1290:8:
> mm/memory.c:1220:23: error: call to ‘__compiletime_assert_1220’ declared with attribute error: BUILD_BUG failed
> mm/memory.c: In function ‘follow_page_mask’:
> mm/memory.c:1530:18: error: call to ‘__compiletime_assert_1530’ declared with attribute error: BUILD_BUG failed
> make[1]: *** [mm/memory.o] Error 1
> make: *** [mm] Error 2
> 
> 
> With -O1 it compiled at least.

You cannot build Linux with -O1/O0.
Try printing the value using printk...

Thanks,
//richard

------------------------------------------------------------------------------
November Webinars for C, C++, Fortran Developers
Accelerate application performance with scalable programming models. Explore
techniques for threading, error checking, porting, and tuning. Get the most 
from the latest Intel processors and coprocessors. See abstracts and register
http://pubads.g.doubleclick.net/gampad/clk?id=60136231&iu=/4140/ostg.clktrk
_______________________________________________
User-mode-linux-devel mailing list
User-mode-linux-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel