Increasing software fault tolerance by employing surprise-removal paths

• US 8,006,120 B2
• Filed: 04/25/2008
• Issued: 08/23/2011
• Est. Priority Date: 01/14/2005
• Status: Active Grant

• 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:
  US12/110,007
• Publication Number:
  US 20080294932A1
• Time in Patent Office: 1,215 Days
• Field of Search: 714/2, 714/33, 714/38, 714/52, 714/15, 714/38.1, 714/38.11, 714/38.12, 714/38.13, 714/38.14, 714/39
• 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 computer-readable storage medium storing computer-executable instructions that, when executed, are configured to implement one or more components, the one or more components comprising:

a first component configured to request a simulated removal of a device responsive to a detection of an error condition associated with the device; and

a second component configured to initiate the simulated removal of the device effective to cause one or more driver components associated with the device to re-enumerate one or more existing driver stacks to facilitate recovery from the error condition, the simulated removal of the device comprising a software simulation of the device being physically removed.

2. The computer-readable storage medium of claim 1, wherein the simulated removal of the device is further configured to cause the one or more driver components to create a subsequent driver stack from which to operate.

3. The computer-readable storage medium of claim 2, wherein the subsequent driver stack is created to exist in parallel with one or more of the existing driver stacks associated with the error condition.

4. The computer-readable storage medium of claim 3, further comprising a third component configured to request the re-enumeration inside a driver layered on top of a device object that was enumerated in the one or more existing driver stacks by the one or more driver components.

5. The computer-readable storage medium of claim 4, wherein the request for the re-enumeration is transmitted from an upper-level driver to a lower-level driver in the one or more existing driver stacks.

6. The computer-readable storage medium of claim 4, wherein the first component comprises one or more of the driver components.

7. The computer-readable storage medium of claim 4, further comprising a fourth component configured to cause one or more of the driver components to create different software states after a re-enumeration sequence.

8. The computer-readable storage medium of claim 1, further comprising one or more application programming interfaces (APIs) configured to enable the one or more driver components to re-enumerate the one or more existing driver stacks.

9. The computer-readable storage medium of claim 8, wherein the one or more APIs are associated with one or more of a device failed functionality, a device set failed functionality, or a re-enumeration functionality.

10. The computer-readable storage medium of claim 1, further comprising a third component configured to reclaim unused resources associated with the one or more existing driver stacks after the one or more existing driver stacks are re-enumerated.

11. The computer-readable storage medium of claim 1, further comprising a third component configured to facilitate negotiations between two or more of an operating system, an application, or the one or more driver components as part of re-enumerating the one or more existing driver stacks.

12. The computer-readable storage medium of claim 1, wherein the one or more existing driver stacks include at least one of a Functional Device Object (FDO), a filter object, and a Physical Device Object (PDO).

13. A computer-implemented method, comprising:

initiating a removal sequence responsive to detecting an error associated with device driver functionality, the removal sequence being configured to simulate, in software, one or more conditions associated with a device being removed from a computing system; and

automatically re-enumerating an existing driver stack responsive to the removal sequence to generate a new driver stack effective to facilitate recovery of the device driver functionality.

14. The computer-implemented method of claim 13, wherein the new driver stack is generated to exist in parallel with the existing driver stack.

15. The computer-implemented method of claim 13, further comprising automatically removing the existing driver stack after the new driver stack is generated.

16. The computer-implemented method of claim 13, wherein the removal sequence is initiated responsive to a request from a device driver associated with the device driver functionality.

17. The computer-implemented method of claim 13, wherein the removal sequence comprises software commands configured to be executed to simulate a hardware event.

18. The computer-implemented method of claim 13, wherein the automatically re-enumerating utilizes an application programming interface (API) that is configured to facilitate the automatically re-enumerating, the API being associated with at least one of a device failed function, a device set failed function, and a re-enumerate function.

19. The computer-implemented method of claim 13, further comprising reclaiming unused resources associated with the existing driver stack after the automatically re-enumerating.

20. A system, comprising:

means for implementing a simulated device removal responsive to detecting an error associated with an existing driver stack, the simulated device removal being configured to simulate, in software, one or more conditions associated with a removal of a physical device associated with the existing driver stack; and

means for generating a new driver stack responsive to the simulated device removal, the new driver stack including at least one driver associated with the existing driver stack.