Windows shortcut to Mute/unMute volume

you can create a Master Volume Shortcut and also assign a Shortcut Key.

Right click on a empty area on desktop, and click on New and Shortcut. 

Paste the following in to the location of the item area:-

%windir%\System32\SndVol.exe -f 49825268

Click Next button and give a name to the Shortcut and click Finish.

Now You right click on it and select Properties.

Click Shortcut tab.

Assign your desired shortcut key like F8 or F9 in the Shortcut Key area.

Click OK/Apply.

Decoding Machine check register exception

Dump

CPU 0: Machine Check Exception: 0000000000000004

CPU 1: Machine Check Exception: 0000000000000005

      Bank 5: b200000802000e0f

Kernel Code snippet:

rdmsr (MSR_IA32_MC0_STATUS+i*4,low, high);  - reads the values of 64 bit machine check registers

        if (high & (1<<31)) {

            if (high & (1<<29))

                recover |= 1;

            if (high & (1<<25))

                recover |= 2;

            printk (KERN_EMERG "Bank %d: %08x%08x", i, high, low);

if (recover & 2)

        panic ("CPU context corrupt");

Decoding : 

( Reference Document)

You will need to browse to Intel’s website hosting Intel® 64 and IA-32 Architectures Software Developer Manuals. There, download a manual named “Intel 64 and IA-32 Architectures Software Developer’s Manual Combined Volumes 3A, 3B, and 3C: System Programming Guide”.

(Reference: https://vmxp.wordpress.com/2014/10/27/debugging-machine-check-errors-mces/comment-page-1/)

IA32_MCi_STATUS MSRS

Each IA32_MCi_STATUS MSR contains information related to a machine-check error if its VAL (valid) flag is set.

Bank 5: b200000802000e0f  - In hex format

63 62 61 60 59 58 57 56 55  54 53      52 - 38                37   36-32         31 - 16                     

1    0  1   1   0   0  1    0  0     00        000000000000000  0    01000   0000 0010 0000 0000   

 15  - 0

0000 1110 0000 1111  ( Bank value in binary format)

63 -  VAL -MCi_STATUS register valid

61 - Uncorrected error

60  - Error reporting enabled

57 - Processor context corrupt

Model specific errors   ( 16 – 31 bits) - Model-specific error code field, bits 31:16

27-25 bits - Bus queue error type

000 for BQ_ERR_HARD_TYPE error

001 for BQ_ERR_DOUBLE_TYPE error   --  It’s Double bit error detected on data read in our case

010 for BQ_ERR_AERR2_TYPE error

100 for BQ_ERR_SINGLE_TYPE error

101 for BQ_ERR_AERR1_TYPE error

0 -15 -  Specifies the machine-check architecture-

defined error code for the machine-check error condition detected

IA32_MCi_Status [15:0] Compound Error Code Encoding