diff options
Diffstat (limited to 'pkg/ring0/entry_amd64.go')
| -rw-r--r-- | pkg/ring0/entry_amd64.go | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/pkg/ring0/entry_amd64.go b/pkg/ring0/entry_amd64.go new file mode 100644 index 000000000..d87b1fd00 --- /dev/null +++ b/pkg/ring0/entry_amd64.go @@ -0,0 +1,131 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build amd64 + +package ring0 + +import ( + "gvisor.dev/gvisor/pkg/sentry/arch" +) + +// This is an assembly function. +// +// The sysenter function is invoked in two situations: +// +// (1) The guest kernel has executed a system call. +// (2) The guest application has executed a system call. +// +// The interrupt flag is examined to determine whether the system call was +// executed from kernel mode or not and the appropriate stub is called. +func sysenter() + +// swapgs swaps the current GS value. +// +// This must be called prior to sysret/iret. +func swapgs() + +// jumpToKernel jumps to the kernel version of the current RIP. +func jumpToKernel() + +// sysret returns to userspace from a system call. +// +// The return code is the vector that interrupted execution. +// +// See stubs.go for a note regarding the frame size of this function. +func sysret(cpu *CPU, regs *arch.Registers, userCR3 uintptr) Vector + +// "iret is the cadillac of CPL switching." +// +// -- Neel Natu +// +// iret is nearly identical to sysret, except an iret is used to fully restore +// all user state. This must be called in cases where all registers need to be +// restored. +func iret(cpu *CPU, regs *arch.Registers, userCR3 uintptr) Vector + +// exception is the generic exception entry. +// +// This is called by the individual stub definitions. +func exception() + +// resume is a stub that restores the CPU kernel registers. +// +// This is used when processing kernel exceptions and syscalls. +func resume() + +// Start is the CPU entrypoint. +// +// The following start conditions must be satisfied: +// +// * AX should contain the CPU pointer. +// * c.GDT() should be loaded as the GDT. +// * c.IDT() should be loaded as the IDT. +// * c.CR0() should be the current CR0 value. +// * c.CR3() should be set to the kernel PageTables. +// * c.CR4() should be the current CR4 value. +// * c.EFER() should be the current EFER value. +// +// The CPU state will be set to c.Registers(). +func Start() + +// Exception stubs. +func divideByZero() +func debug() +func nmi() +func breakpoint() +func overflow() +func boundRangeExceeded() +func invalidOpcode() +func deviceNotAvailable() +func doubleFault() +func coprocessorSegmentOverrun() +func invalidTSS() +func segmentNotPresent() +func stackSegmentFault() +func generalProtectionFault() +func pageFault() +func x87FloatingPointException() +func alignmentCheck() +func machineCheck() +func simdFloatingPointException() +func virtualizationException() +func securityException() +func syscallInt80() + +// Exception handler index. +var handlers = map[Vector]func(){ + DivideByZero: divideByZero, + Debug: debug, + NMI: nmi, + Breakpoint: breakpoint, + Overflow: overflow, + BoundRangeExceeded: boundRangeExceeded, + InvalidOpcode: invalidOpcode, + DeviceNotAvailable: deviceNotAvailable, + DoubleFault: doubleFault, + CoprocessorSegmentOverrun: coprocessorSegmentOverrun, + InvalidTSS: invalidTSS, + SegmentNotPresent: segmentNotPresent, + StackSegmentFault: stackSegmentFault, + GeneralProtectionFault: generalProtectionFault, + PageFault: pageFault, + X87FloatingPointException: x87FloatingPointException, + AlignmentCheck: alignmentCheck, + MachineCheck: machineCheck, + SIMDFloatingPointException: simdFloatingPointException, + VirtualizationException: virtualizationException, + SecurityException: securityException, + SyscallInt80: syscallInt80, +} |