"Transition to non-recoverable" machine check error

Hi. now iam using PowerEdge R815 with 4 AMD opteron 6272 processors.

I got a system event log with system halt as follows

Sensor ID : CPU Machine Chk (0xd)

Description : Transition to Non-recoverable

Entity ID : 34.1

Generator ID : 00b1

I want to know the error code for the machine check error which is described in AMD specification document (BKDG 15h)

As far as I know, if there is machine check error, I can get error code MCA status register (e.g. MC0 ~ MC6) after next warm reset.

But,  after warm reset, there was not any machine check error in the MCA status register(I make some linux device driver to read MCA status register)

the first question is that 

am i correct about the procedure to get error message from AMD MCA ?

the second question is that

Then, how can i get the error code which cause the machine check error ?

the third question is that

What does "transition to non-recoverable" means ???

Thanks.