Michael J Swift

US Patent:

7673174, Mar 2, 2010

Filed:

Apr 6, 2006

Appl. No.:

11/398799

Inventors:

Michael Swift - Madison WI, US
Brian Bershad - Seattle WA, US
Hank Levy - Seattle WA, US

Assignee:

University of Washington - Seattle WA

International Classification:

G06F 11/00

US Classification:

714 15, 714 2, 719321

Abstract:

A solution to the problem of maintaining application integrity when device drivers fail. This solution employs a new mechanism, the shadow driver, which is an operating system (OS) kernel agent that monitors communication between the OS kernel and the device driver it “shadows. ” When a device driver error occurs, the shadow driver acts in place of the failed device driver, intercepting and responding to calls from the OS kernel and the device driver during cleanup, unloading, reloading, and re-initialization of the failed device driver. Applications and the OS kernel are thus isolated from the failure. An initial embodiment was developed for use with the Linux™ OS and was tested with a dozen device drivers. Results demonstrate that shadow drivers successfully mask device driver failures from applications, impose minimal performance overhead, require no changes to existing applications and device drivers, and can be implemented with relatively little code.

US Patent:

8239633, Aug 7, 2012

Filed:

Jul 9, 2008

Appl. No.:

12/217811

Inventors:

David A. Wood - Madison WI, US
Mark D. Hill - Madison WI, US
Michael M. Swift - Madison WI, US
Michael R. Marty - Madison WI, US
Luke Yen - Fitchburg WI, US
Kevin E. Moore - Mill Valley CA, US
Jayaram Bobba - Madison WI, US
Haris Volos - Madison WI, US

Assignee:

Wisconsin Alumni Research Foundation - Madison WI

International Classification:

G06F 12/08

US Classification:

711141, 711E12026

Abstract:

A coherence controller in hardware of an apparatus in an example detects conflicts on coherence requests through direct, non-broadcast employment of signatures that: summarize read-sets and write-sets of memory transactions; and provide false positives but no false negatives for the conflicts on the coherence requests. The signatures comprise fixed-size representations of a substantially arbitrary set of addresses for the read-sets and the write-sets of the memory transactions.

US Patent:

8510597, Aug 13, 2013

Filed:

Feb 8, 2011

Appl. No.:

13/023354

Inventors:

Michael M. Swift - Madison WI, US
Andrea C. Arpaci-Dusseau - Madison WI, US
Remzi H. Arpaci-Dusseau - Madison WI, US
Swaminathan Sundararaman - Madison WI, US
Sriram Subramanian - Madison WI, US
Abhishek Rajimwale - Santa Clara CA, US

Assignee:

Wisconsin Alumni Research Foundation - Madison WI

International Classification:

G06F 11/00

US Classification:

714 15, 714 2

Abstract:

In general, techniques are described for enabling a restartable file system. A computing device comprising a processor that executes an operating system may implement the techniques. The processor executes kernel and file system functions of the operating system to perform an operation, where both types of functions call each other to perform the operation. The operating system stores data identifying those of the kernel functions that called the file system functions. In response to determining that one of the file system functions that was called has failed, the operating system accesses the data to identify one of the kernel functions that most recently called one of the file system functions, and returns control to the identified one of the kernel functions without executing any of the file system functions called after the identified one of the kernel functions and prior to the one of the file system functions that failed.

US Patent:

20160246730, Aug 25, 2016

Filed:

Feb 20, 2015

Appl. No.:

14/627472

Inventors:

- Madison WI, US
Mark D. Hill - Madison WI, US
Michael M. Swift - Madison WI, US

International Classification:

G06F 12/10

Abstract:

The translation of virtual guest addresses to host physical addresses in a virtualized computer system provides a compound page table that may simultaneously support nested-paging and shadow-paging for different memory regions. Memory regions with stable address mapping, for example, holding program code, may be treated using shadow-paging while memory regions with dynamic address mapping, for example, variable storage, may be treated using nested-paging thereby obtaining the benefits of both techniques.

US Patent:

20150067296, Mar 5, 2015

Filed:

Aug 28, 2013

Appl. No.:

14/012261

Inventors:

- Madison WI, US
Mark D. Hill - Madison WI, US
Michael M. Swift - Madison WI, US

Assignee:

Wisconsin Alumni Research Foundation - Madison WI

International Classification:

G06F 12/10

US Classification:

711206

Abstract:

A memory management unit for 110 devices uses page table entries to translate virtual addresses to physical addresses. The page table entries include removal rules allowing the I/O memory management unit to delete page table entries without CPU involvement significantly reducing the CPU overhead involved in virtualized I/O data transactions.

US Patent:

20140208064, Jul 24, 2014

Filed:

Jan 24, 2013

Appl. No.:

13/749334

Inventors:

- Madison WI, US
Mark Donald Hill - Madison WI, US
Michael Mansfield Swift - Madison WI, US

Assignee:

Wisconsin Alumni Research Foundation - Madison WI

International Classification:

G06F 12/10

US Classification:

711207

Abstract:

A computer system using virtual memory provides hybrid memory access either through a conventional translation between virtual memory and physical memory using a page table possibly with a translation lookaside buffer, or a high-speed translation using a fixed offset value between virtual memory and physical memory. Selection between these modes of access may be encoded into the address space of virtual memory eliminating the need for a separate tagging operation of specific memory addresses.

US Patent:

20140199768, Jul 17, 2014

Filed:

Mar 18, 2014

Appl. No.:

14/217478

Inventors:

- Chicago IL, US
Finley Miller - Huntington Beach CA, US
Michael R. Swift - Enfield CT, US

Assignee:

The Boeing Company - Chicago IL

International Classification:

G01N 21/78
G01N 31/22

US Classification:

436 1, 422408

Abstract:

A device indicates the location of an air leak in a vacuum bag used to process composite parts. The device includes a layer of material on the inner face of the bag that changes in appearance due to an oxidation-reduction reaction in areas of the layer exposed to oxygen caused by a leak in the bag.