Increasing software fault tolerance by employing surprise-removal paths

• US 7,366,944 B2
• Filed: 01/14/2005
• Issued: 04/29/2008
• Est. Priority Date: 01/14/2005
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Holan, Doron J., Oshins, Jacob
• Primary Examiner(s): LE, DIEU MINH T
• Application Number:
  US11/036,803
• Publication Number:
  US 20060161821A1
• Time in Patent Office: 1,201 Days
• Field of Search: 714/52, 714/763, 714/2, 714/15, 714/16, 714/33, 714/38, 711/161, 717/135
• US Class Current: 714/2
• CPC Class Codes: G06F 11/1438 Restarting or rejuvenating

Abstract

The subject invention relates to systems and methods for automatic recovery from errors in a computing environment. A system is provided to facilitate failure recovery in the computing system. The system includes at least one driver component that enumerates at least one layer of a driver stack. A module associated with the driver component requests re-enumeration of the driver stack upon detection of an error in the computing system. When an error is detected by a driver or operating system component, a protocol can be established whereby a new copy of the driver'"'"'s stack or system resources is re-enumerated in parallel to existing resources that may be in an unknown or error state. The new copy of the stack may allow the driver to become operational in lieu of the previous stack which can be reclaimed for other system uses over time.

Claims

1. A system to facilitate failure recovery in a computing environment, comprising:

a computer processor that executes the following software components;

at least one driver component that enumerates at least one layer of a driver stack;

a module associated with the driver component that facilitates re-enumeration of the driver stack upon detection of an error in the computing system;

an operating system framework that interacts with the at least one driver component to facilitate operations with hardware and software components of the computing system;

the framework, via a message protocol, initiates a surprise removal sequence which simulates in software the conditions of the module being removed from the computing system, the simulation causes the at least one driver component to create a subsequent driver stack from which to operate; and

the subsequent driver stack is created in parallel with the previous stack that encountered the error in order to attempt to resume normal operations of the at least one driver component.

2. The system of claim 1, the module requests re-enumeration inside a driver layered on top of a device object that was enumerated by the at least one driver component.

3. The system of claim 2, the requests for re-enumeration is transmitted from an upper-level driver to a lower-level driver.

4. The system of claim 2, the requests for re-enumeration is responded to by the at least one driver by a signal that indicates a device is absent.

5. The system of claim 2, further comprising a component to cause drivers in a stack of drivers to create different software states after a re-enumeration sequence.

6. The system of claim 1, further comprising one or more application programming interfaces (APIs) to facilitate the re-enumeration.

7. The system of claim 6, the APIs are associated with a device failed functionality, a device set failed functionality, or a re-enumeration functionality.

8. The system of claim 6, further comprising a message protocol that is associated with an I/O invalidate function, a query device relations function, or a list device object function.

9. The system of claim 1, further comprising a component to reclaim unused resources after the re-enumeration.

10. The system of claim 1, further comprising a component to facilitate negotiations between an operating system, an application, or a driver in accordance with the re-enumeration.

11. The system of claim 1, the stack includes at least one of a Functional Device Object (FDO), a filter object, and a Physical Device Object (PDO).

12. The system of claim 1, the module and the at least one driver share interface functions to facilitate the re-enumeration.

13. A system for detecting and correcting errors in a computer, the system is recorded on a computer storage medium and executed by a processor, comprising:

means for creating a driver stack;

means for interfacing to the stack;

means for detecting errors with the stack;

means for re-creating a new stack upon detecting the errors; and

means for initiating a surprise removal sequence which simulates in software the conditions of a module being removed from a computing system, the simulation causes the re-creation of the new stack from which to operate.

14. A method for failure recovery in computer systems, comprising:

creating an instance of a stack to enable driver functionality;

detecting a fault with the driver functionality;

automatically negotiating with a framework component when detecting the fault;

automatically creating a new instance of the stack after detecting the fault in order to facilitate recovery of the driver functionality;

initiating, via a message protocol, a surprise removal sequence which simulates in software the conditions of a module being removed from a computing system, the simulation causes the creation of the new instance of the stack from which to operate; and

creating the new instance of the stack in parallel with the previous instance of the stack that encountered an error in order to attempt to resume normal operations of the driver functionality.

15. The method of claim 14, further comprising automatically removing previous instances of the stack.

16. The method of claim 14, further comprising initiating a message protocol between at least two components after detecting the fault.

17. The method of claim 16, the message protocol employs software commands to simulate a hardware event.

18. The method of claim 17, the message protocol is associated with a listing of device objects.

19. The method of claim 16, the message protocol is associated with an application programming interface (API), the API is associated with at least one of a device failed function, a device set failed function, and a re-enumerate function.