Raytheon Company

Nightwing Group, Llc.

The United States of America, As Represented by the Secretary, Department of Health and Human Services

Gregory Price

Che-Hung Robert Lee

William Wysocki

Margaret C Bash

Matthew A Taylor

Alex Grundwerg

Michael Swan

Justin Moore

A method for use in a computing device, the method comprising: transmitting, to a context manager, a context request associated with a process that is executed in a virtual machine; receiving, from the context manager, a context identifier in response to the context request; transmitting, to an introspection Application Programming Interface (API), a memory access request that is based, at least in part, on the context identifier.

Concurrent kernel and user space debugging of guest software on a virtual machine in the presence of page table isolation

A method is provided comprising: monitoring, by a symbol context manager, context switch events that are generated in a virtual machine, and updating a symbol space map based on the context switch events; receiving, by the symbol context manager, a request to provide a symbol space of the virtual machine, the request being generated by a symbol database interface in response to a symbol query that is received at the symbol database interface from a debugger that is debugging the virtual machine, the symbol query being associated with a symbol that is part of the symbol space; and providing, by the symbol context manager, an indication of the symbol space of the virtual machine, the indication of the symbol space being provided based on the symbol space map.

Symbol mapping system for concurrent kernel and user space debugging of a virtual machine

Techniques are disclosed for dynamic access and instrumentation of model specific registers (MSRs). A virtual machine monitor (VMM) can provide a kernel application program interface (API) that can be utilized to access and instrument an MSR. A method may include receiving, by the VMM, an MSR instrumentation command that identifies an MSR to instrument and causing instrumentation of the MSR identified in the MSR instrumentation command. Instrumentation of the identified MSR can be caused by configuring or manipulating a virtual machine control structure (VMCS) of a guest virtual machine (VM). The MSR instrumentation command may be an MSR instrumentation request command, an MSR remove request command, an MSR value set request command, or an MSR value fetch request command. In some cases, the VMM may be a Type-I hypervisor.

Model specific register (MSR) instrumentation

Techniques are disclosed for interposing on nondeterministic events during multicore virtual machine (VM) execution to capture information that allows for deterministically recreating the nondeterministic events during execution replay of the VM. A method may include reading, by a virtual processor running within a multicore VM instance, an instruction to execute, and, responsive to a determination that the instruction is a nondeterministic instruction, interposing on the nondeterministic instruction execution so as to allow deterministic execution of the nondeterministic instruction during replay execution of the multicore VM instance. Interposing on the nondeterministic instruction execution may include recording a partial barrier event and/or a full barrier event. The nondeterministic instruction may be a read memory access instruction or a write memory access instruction.

Deterministic execution replay for multicore systems

According to aspects of the disclosure a method is provided, comprising: generating a live execution trace log corresponding to a live execution of a computer program, the live execution being performed by using both hardware emulation and hardware acceleration; generating a first trace entry corresponding to a replay execution of the computer program, the replay execution being performed by using hardware emulation without hardware acceleration, the replay execution being performed based on a set of events that are recorded during the live execution of the computer program; detecting whether the first trace entry is valid based on the live execution trace log; and in response to detecting that the first trace entry is not valid, transitioning into a safe state.

Architecture agnostic replay verfication

Immunogenic compositions that include a bacterial capsular polysaccharide conjugated to a carrier protein are described. In some embodiments, the bacterial capsular polysaccharide is acapsular polysaccharide. The carrier protein includes anfactor H binding protein (fHbp) linked to cholera toxin subunit B (CTB). Administration of the immunogenic compositions elicits an immune response that includes production of meningococcal polysaccharide-specific and fHbp-specific antibodies. Use of the immunogenic compositions as meningococcal vaccines is also described.

Growing community of inventors

Silver Spring, MD, United States of America

Gregory Price