diff options
Diffstat (limited to 'pkg/sentry/platform/kvm')
| -rw-r--r-- | pkg/sentry/platform/kvm/kvm_arm64.go | 4 | ||||
| -rw-r--r-- | pkg/sentry/platform/kvm/machine_arm64_unsafe.go | 63 |
2 files changed, 3 insertions, 64 deletions
diff --git a/pkg/sentry/platform/kvm/kvm_arm64.go b/pkg/sentry/platform/kvm/kvm_arm64.go index 79045651e..716198712 100644 --- a/pkg/sentry/platform/kvm/kvm_arm64.go +++ b/pkg/sentry/platform/kvm/kvm_arm64.go @@ -18,6 +18,8 @@ package kvm import ( "syscall" + + "gvisor.dev/gvisor/pkg/sentry/platform/ring0" ) type kvmOneReg struct { @@ -46,6 +48,6 @@ type userRegs struct { func updateGlobalOnce(fd int) error { physicalInit() err := updateSystemValues(int(fd)) - updateVectorTable() + ring0.Init() return err } diff --git a/pkg/sentry/platform/kvm/machine_arm64_unsafe.go b/pkg/sentry/platform/kvm/machine_arm64_unsafe.go index b531f2f85..3b35858ae 100644 --- a/pkg/sentry/platform/kvm/machine_arm64_unsafe.go +++ b/pkg/sentry/platform/kvm/machine_arm64_unsafe.go @@ -48,69 +48,6 @@ func (m *machine) initArchState() error { return nil } -func getPageWithReflect(p uintptr) []byte { - return (*(*[0xFFFFFF]byte)(unsafe.Pointer(p & ^uintptr(syscall.Getpagesize()-1))))[:syscall.Getpagesize()] -} - -// Work around: move ring0.Vectors() into a specific address with 11-bits alignment. -// -// According to the design documentation of Arm64, -// the start address of exception vector table should be 11-bits aligned. -// Please see the code in linux kernel as reference: arch/arm64/kernel/entry.S -// But, we can't align a function's start address to a specific address by using golang. -// We have raised this question in golang community: -// https://groups.google.com/forum/m/#!topic/golang-dev/RPj90l5x86I -// This function will be removed when golang supports this feature. -// -// There are 2 jobs were implemented in this function: -// 1, move the start address of exception vector table into the specific address. -// 2, modify the offset of each instruction. -func updateVectorTable() { - fromLocation := reflect.ValueOf(ring0.Vectors).Pointer() - offset := fromLocation & (1<<11 - 1) - if offset != 0 { - offset = 1<<11 - offset - } - - toLocation := fromLocation + offset - page := getPageWithReflect(toLocation) - if err := syscall.Mprotect(page, syscall.PROT_READ|syscall.PROT_WRITE|syscall.PROT_EXEC); err != nil { - panic(err) - } - - page = getPageWithReflect(toLocation + 4096) - if err := syscall.Mprotect(page, syscall.PROT_READ|syscall.PROT_WRITE|syscall.PROT_EXEC); err != nil { - panic(err) - } - - // Move exception-vector-table into the specific address. - var entry *uint32 - var entryFrom *uint32 - for i := 1; i <= 0x800; i++ { - entry = (*uint32)(unsafe.Pointer(toLocation + 0x800 - uintptr(i))) - entryFrom = (*uint32)(unsafe.Pointer(fromLocation + 0x800 - uintptr(i))) - *entry = *entryFrom - } - - // The offset from the address of each unconditionally branch is changed. - // We should modify the offset of each instruction. - nums := []uint32{0x0, 0x80, 0x100, 0x180, 0x200, 0x280, 0x300, 0x380, 0x400, 0x480, 0x500, 0x580, 0x600, 0x680, 0x700, 0x780} - for _, num := range nums { - entry = (*uint32)(unsafe.Pointer(toLocation + uintptr(num))) - *entry = *entry - (uint32)(offset/4) - } - - page = getPageWithReflect(toLocation) - if err := syscall.Mprotect(page, syscall.PROT_READ|syscall.PROT_EXEC); err != nil { - panic(err) - } - - page = getPageWithReflect(toLocation + 4096) - if err := syscall.Mprotect(page, syscall.PROT_READ|syscall.PROT_EXEC); err != nil { - panic(err) - } -} - // initArchState initializes architecture-specific state. func (c *vCPU) initArchState() error { var ( |