RE: [PATCH] xen/mce: add .poll method for mcelog device driver

[Liu, Jinsong]

 Liu, Jinsong wrote:
>>> So another bug which is that mcelog is spinning at 100% CPU (and
>>> only under Xen). 
>>> 
>>> It seems to be doing:
>>> 
>>> ppoll([{fd=4, events=POLLIN}, {fd=3, events=POLLIN}], 2, NULL, [],
>>> 8) = 1 ([{fd=3, revents=POLLIN}]) read(3, "", 2816)
>>> = 0
>>> ppoll([{fd=4, events=POLLIN}, {fd=3, events=POLLIN}], 2, NULL, [],
>>> 8) = 1 ([{fd=3, revents=POLLIN}]) read(3, "", 2816)
>>> 
>>> constantly.
>> 
>> I will debug it. I have try at my platform, but fail to reproduce it.
>> (You still use the config you send me last time, right?) Would you
>> tell me your step? 
>> 
>> Thanks,
>> Jinsong
> 
> Have a look at it, it caused by NULL .poll method.
> Attached is the patch to fix this bug, but I cannot reproduce the bug
> at my platform, so would you please help me to test it at your side? 
> 

Ah I know how you trigger the bug - you run mcelog as daemon ... then spinning at CPU.
I update my patch as attached, and test at my platform OK now.

Thanks,
Jinsong

========================