Driver Verifier
Encyclopedia
Driver Verifier is a tool included in Microsoft Windows
that replaces the default operating system subroutine
s with ones that are specifically developed to catch device driver
bug
s. Once enabled, it monitors and stresses drivers to detect illegal function calls
or actions that may be causing system corruption. It acts within the kernel mode and can target specific device drivers for continual checking or make driver verifier functionality multithreaded
, so that several device drivers can be stressed at the same time. It can simulate certain conditions such as low memory, I/O
verification, pool
tracking, IRQL checking, deadlock
detection, DMA
checks, IRP logging etc. The verifier works by forcing drivers to work with minimal resources, making potential errors that might happen only rarely in a working system manifest immediately. Typically fatal system errors are generated by the stressed drivers in the test environment, producing core dump
s which can be analysed and debugged
immediately; without stressing, intermittent fault
s would occur in the field, without proper troubleshooting
facilities or personnel.
Driver Verifier (Verifier.exe) was first introduced as a command-line utility in Windows 2000
; in Windows XP
, it gained an easy to use graphical user interface, called Driver Verifier Manager using which it is possible to enable a standard or custom set of settings to select which drivers to test and verify. Each new Windows version has since introduced several new, more stringent checks for testing and verifying drivers and detecting new classes of driver defects.
Driver Verifier is not normally used on machines being used for productive work. It can cause undetected and relatively harmless errors in drivers to manifest, especially ones which are not digitally signed by Windows Hardware Quality Labs, causing blue screen
fatal system errors. It also causes resource-starved drivers to underperform and slow general operation if the constraints imposed by verifier are not reversed after debugging. Microsoft recommends not all drivers should be verified at the same time.
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
that replaces the default operating system subroutine
Subroutine
In computer science, a subroutine is a portion of code within a larger program that performs a specific task and is relatively independent of the remaining code....
s with ones that are specifically developed to catch device driver
Device driver
In computing, a device driver or software driver is a computer program allowing higher-level computer programs to interact with a hardware device....
bug
Software bug
A software bug is the common term used to describe an error, flaw, mistake, failure, or fault in a computer program or system that produces an incorrect or unexpected result, or causes it to behave in unintended ways. Most bugs arise from mistakes and errors made by people in either a program's...
s. Once enabled, it monitors and stresses drivers to detect illegal function calls
Subroutine
In computer science, a subroutine is a portion of code within a larger program that performs a specific task and is relatively independent of the remaining code....
or actions that may be causing system corruption. It acts within the kernel mode and can target specific device drivers for continual checking or make driver verifier functionality multithreaded
Thread (computer science)
In computer science, a thread of execution is the smallest unit of processing that can be scheduled by an operating system. The implementation of threads and processes differs from one operating system to another, but in most cases, a thread is contained inside a process...
, so that several device drivers can be stressed at the same time. It can simulate certain conditions such as low memory, I/O
Input/output
In computing, input/output, or I/O, refers to the communication between an information processing system , and the outside world, possibly a human, or another information processing system. Inputs are the signals or data received by the system, and outputs are the signals or data sent from it...
verification, pool
Memory pool
Memory pools, also called fixed-size-blocks allocation, allow dynamic memory allocation comparable to malloc or C++'s operator new. As those implementations suffer from fragmentation because of variable block sizes, it can be impossible to use them in a real time system due to performance...
tracking, IRQL checking, deadlock
Deadlock
A deadlock is a situation where in two or more competing actions are each waiting for the other to finish, and thus neither ever does. It is often seen in a paradox like the "chicken or the egg"...
detection, DMA
Direct memory access
Direct memory access is a feature of modern computers that allows certain hardware subsystems within the computer to access system memory independently of the central processing unit ....
checks, IRP logging etc. The verifier works by forcing drivers to work with minimal resources, making potential errors that might happen only rarely in a working system manifest immediately. Typically fatal system errors are generated by the stressed drivers in the test environment, producing core dump
Core dump
In computing, a core dump consists of the recorded state of the working memory of a computer program at a specific time, generally when the program has terminated abnormally...
s which can be analysed and debugged
Debugging
Debugging is a methodical process of finding and reducing the number of bugs, or defects, in a computer program or a piece of electronic hardware, thus making it behave as expected. Debugging tends to be harder when various subsystems are tightly coupled, as changes in one may cause bugs to emerge...
immediately; without stressing, intermittent fault
Intermittent Fault
An intermittent fault, often called simply an "intermittent", is a malfunction of a device or system that occurs at intervals, usually irregular, in a device or system that functions normally at other times. Intermittent faults are common to all branches of technology, including computer software...
s would occur in the field, without proper troubleshooting
Troubleshooting
Troubleshooting is a form of problem solving, often applied to repair failed products or processes. It is a logical, systematic search for the source of a problem so that it can be solved, and so the product or process can be made operational again. Troubleshooting is needed to develop and...
facilities or personnel.
Driver Verifier (Verifier.exe) was first introduced as a command-line utility in Windows 2000
Windows 2000
Windows 2000 is a line of operating systems produced by Microsoft for use on personal computers, business desktops, laptops, and servers. Windows 2000 was released to manufacturing on 15 December 1999 and launched to retail on 17 February 2000. It is the successor to Windows NT 4.0, and is the...
; in Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
, it gained an easy to use graphical user interface, called Driver Verifier Manager using which it is possible to enable a standard or custom set of settings to select which drivers to test and verify. Each new Windows version has since introduced several new, more stringent checks for testing and verifying drivers and detecting new classes of driver defects.
Driver Verifier is not normally used on machines being used for productive work. It can cause undetected and relatively harmless errors in drivers to manifest, especially ones which are not digitally signed by Windows Hardware Quality Labs, causing blue screen
Blue Screen of Death
To forse a BSOD Open regedit.exe,Then search: HKLM\SYSTEM\CurrentControlSet\services\i8042prt\ParametersThen make a new DWORD called "CrashOnCtrlScroll" And set the value to 1....
fatal system errors. It also causes resource-starved drivers to underperform and slow general operation if the constraints imposed by verifier are not reversed after debugging. Microsoft recommends not all drivers should be verified at the same time.