[x264-devel] Bus error

[Zubair Ali Khan]

Måns Rullgård wrote:
> Zubair Ali Khan <zkhan at d2tech.com> writes:
>
>   
>>>> This is trying to write to an unaligned address, which the CPU does
>>>> support unless disabled.  What does /proc/cpu/alignment contain?
>>>>
>>>>
>>>>         
>> cat /proc/cpu/alignment
>> User:           5
>> System:         0
>> Skipped:        0
>> Half:           0
>> Word:           0
>> DWord:          0
>> Multi:          0
>> User faults:    4 (signal)
>>     
>
> As root, run "echo 2 > /proc/cpu/alignment".  That will allow
> unaligned accesses.
>
>   
I did echo 2 > /proc/cpu/alignment as you said.
cat 
/proc/cpu/alignment                                                      
User:           
0                                                              
System:         
0                                                              
Skipped:        
0                                                              
Half:           
0                                                              
Word:           
0                                                              
DWord:          
0                                                              
Multi:          
0                                                              
User faults:    2 (fixup)   

Then the program ran, and did not receive SIGBUS. I hope changing kernel 
alignment behavior to fixup does not waste too many cycles. Thanks.