Merge release-20200323.0-251-g3c67754 (automated)

31 files changed, 521 insertions, 236 deletions

diff --git a/pkg/sentry/arch/arch_aarch64.go b/pkg/sentry/arch/arch_aarch64.go
index c29e1b841..529980267 100755
--- a/pkg/sentry/arch/arch_aarch64.go
+++ b/pkg/sentry/arch/arch_aarch64.go
@@ -17,18 +17,20 @@
 package arch
 
 import (
+	"encoding/binary"
 	"fmt"
 	"io"
-	"syscall"
 
-	"gvisor.dev/gvisor/pkg/binary"
+	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/cpuid"
 	"gvisor.dev/gvisor/pkg/log"
 	rpb "gvisor.dev/gvisor/pkg/sentry/arch/registers_go_proto"
 	"gvisor.dev/gvisor/pkg/syserror"
-	"gvisor.dev/gvisor/pkg/usermem"
 )
 
+// Registers represents the CPU registers for this architecture.
+type Registers = linux.PtraceRegs
+
 const (
 	// SyscallWidth is the width of insturctions.
 	SyscallWidth = 4
@@ -90,7 +92,7 @@ func NewFloatingPointData() *FloatingPointData {
 // file ensures it's only built on aarch64).
 type State struct {
 	// The system registers.
-	Regs syscall.PtraceRegs `state:".(syscallPtraceRegs)"`
+	Regs Registers
 
 	// Our floating point state.
 	aarch64FPState `state:"wait"`
@@ -226,25 +228,27 @@ func (s *State) RegisterMap() (map[string]uintptr, error) {
 
 // PtraceGetRegs implements Context.PtraceGetRegs.
 func (s *State) PtraceGetRegs(dst io.Writer) (int, error) {
-	return dst.Write(binary.Marshal(nil, usermem.ByteOrder, s.ptraceGetRegs()))
+	regs := s.ptraceGetRegs()
+	n, err := regs.WriteTo(dst)
+	return int(n), err
 }
 
-func (s *State) ptraceGetRegs() syscall.PtraceRegs {
+func (s *State) ptraceGetRegs() Registers {
 	return s.Regs
 }
 
-var ptraceRegsSize = int(binary.Size(syscall.PtraceRegs{}))
+var registersSize = (*Registers)(nil).SizeBytes()
 
 // PtraceSetRegs implements Context.PtraceSetRegs.
 func (s *State) PtraceSetRegs(src io.Reader) (int, error) {
-	var regs syscall.PtraceRegs
-	buf := make([]byte, ptraceRegsSize)
+	var regs Registers
+	buf := make([]byte, registersSize)
 	if _, err := io.ReadFull(src, buf); err != nil {
 		return 0, err
 	}
-	binary.Unmarshal(buf, usermem.ByteOrder, &regs)
+	regs.UnmarshalUnsafe(buf)
 	s.Regs = regs
-	return ptraceRegsSize, nil
+	return registersSize, nil
 }
 
 // PtraceGetFPRegs implements Context.PtraceGetFPRegs.
diff --git a/pkg/sentry/arch/arch_aarch64_abi_autogen_unsafe.go b/pkg/sentry/arch/arch_aarch64_abi_autogen_unsafe.go
new file mode 100755
index 000000000..f7a3597d4
--- /dev/null
+++ b/pkg/sentry/arch/arch_aarch64_abi_autogen_unsafe.go
@@ -0,0 +1,9 @@
+// Automatically generated marshal implementation. See tools/go_marshal.
+
+// +build arm64
+
+package arch
+
+import (
+)
+
diff --git a/pkg/sentry/arch/arch_aarch64_state_autogen.go b/pkg/sentry/arch/arch_aarch64_state_autogen.go
index 9c6dfdf2e..49f2e3d67 100755
--- a/pkg/sentry/arch/arch_aarch64_state_autogen.go
+++ b/pkg/sentry/arch/arch_aarch64_state_autogen.go
@@ -1,6 +1,5 @@
 // automatically generated by stateify.
 
 // +build arm64
-// +build arm64
 
 package arch
diff --git a/pkg/sentry/arch/arch_abi_autogen_unsafe.go b/pkg/sentry/arch/arch_abi_autogen_unsafe.go
new file mode 100755
index 000000000..3e94c6144
--- /dev/null
+++ b/pkg/sentry/arch/arch_abi_autogen_unsafe.go
@@ -0,0 +1,372 @@
+// Automatically generated marshal implementation. See tools/go_marshal.
+
+// +build amd64 386
+// +build amd64 386
+// +build 386 amd64 arm64
+
+package arch
+
+import (
+    "gvisor.dev/gvisor/pkg/abi/linux"
+    "gvisor.dev/gvisor/pkg/gohacks"
+    "gvisor.dev/gvisor/pkg/safecopy"
+    "gvisor.dev/gvisor/pkg/usermem"
+    "gvisor.dev/gvisor/tools/go_marshal/marshal"
+    "io"
+    "reflect"
+    "runtime"
+    "unsafe"
+)
+
+// Marshallable types used by this file.
+var _ marshal.Marshallable = (*SignalAct)(nil)
+var _ marshal.Marshallable = (*SignalInfo)(nil)
+var _ marshal.Marshallable = (*SignalStack)(nil)
+var _ marshal.Marshallable = (*linux.SignalSet)(nil)
+
+// SizeBytes implements marshal.Marshallable.SizeBytes.
+func (s *SignalAct) SizeBytes() int {
+    return 24 +
+        (*linux.SignalSet)(nil).SizeBytes()
+}
+
+// MarshalBytes implements marshal.Marshallable.MarshalBytes.
+func (s *SignalAct) MarshalBytes(dst []byte) {
+    usermem.ByteOrder.PutUint64(dst[:8], uint64(s.Handler))
+    dst = dst[8:]
+    usermem.ByteOrder.PutUint64(dst[:8], uint64(s.Flags))
+    dst = dst[8:]
+    usermem.ByteOrder.PutUint64(dst[:8], uint64(s.Restorer))
+    dst = dst[8:]
+    s.Mask.MarshalBytes(dst[:s.Mask.SizeBytes()])
+    dst = dst[s.Mask.SizeBytes():]
+}
+
+// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
+func (s *SignalAct) UnmarshalBytes(src []byte) {
+    s.Handler = uint64(usermem.ByteOrder.Uint64(src[:8]))
+    src = src[8:]
+    s.Flags = uint64(usermem.ByteOrder.Uint64(src[:8]))
+    src = src[8:]
+    s.Restorer = uint64(usermem.ByteOrder.Uint64(src[:8]))
+    src = src[8:]
+    s.Mask.UnmarshalBytes(src[:s.Mask.SizeBytes()])
+    src = src[s.Mask.SizeBytes():]
+}
+
+// Packed implements marshal.Marshallable.Packed.
+//go:nosplit
+func (s *SignalAct) Packed() bool {
+    return s.Mask.Packed()
+}
+
+// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
+func (s *SignalAct) MarshalUnsafe(dst []byte) {
+    if s.Mask.Packed() {
+        safecopy.CopyIn(dst, unsafe.Pointer(s))
+    } else {
+        s.MarshalBytes(dst)
+    }
+}
+
+// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
+func (s *SignalAct) UnmarshalUnsafe(src []byte) {
+    if s.Mask.Packed() {
+        safecopy.CopyOut(unsafe.Pointer(s), src)
+    } else {
+        s.UnmarshalBytes(src)
+    }
+}
+
+// CopyOutN implements marshal.Marshallable.CopyOutN.
+//go:nosplit
+func (s *SignalAct) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
+    if !s.Mask.Packed() {
+        // Type SignalAct doesn't have a packed layout in memory, fall back to MarshalBytes.
+        buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
+        s.MarshalBytes(buf) // escapes: fallback.
+        return task.CopyOutBytes(addr, buf[:limit]) // escapes: okay.
+    }
+
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := task.CopyOutBytes(addr, buf[:limit]) // escapes: okay.
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return length, err
+}
+
+// CopyOut implements marshal.Marshallable.CopyOut.
+//go:nosplit
+func (s *SignalAct) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
+    return s.CopyOutN(task, addr, s.SizeBytes())
+}
+
+// CopyIn implements marshal.Marshallable.CopyIn.
+//go:nosplit
+func (s *SignalAct) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
+    if !s.Mask.Packed() {
+        // Type SignalAct doesn't have a packed layout in memory, fall back to UnmarshalBytes.
+        buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
+        length, err := task.CopyInBytes(addr, buf) // escapes: okay.
+        // Unmarshal unconditionally. If we had a short copy-in, this results in a
+        // partially unmarshalled struct.
+        s.UnmarshalBytes(buf) // escapes: fallback.
+        return length, err
+    }
+
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := task.CopyInBytes(addr, buf) // escapes: okay.
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return length, err
+}
+
+// WriteTo implements io.WriterTo.WriteTo.
+func (s *SignalAct) WriteTo(w io.Writer) (int64, error) {
+    if !s.Mask.Packed() {
+        // Type SignalAct doesn't have a packed layout in memory, fall back to MarshalBytes.
+        buf := make([]byte, s.SizeBytes())
+        s.MarshalBytes(buf)
+        length, err := w.Write(buf)
+        return int64(length), err
+    }
+
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := w.Write(buf)
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return int64(length), err
+}
+
+// SizeBytes implements marshal.Marshallable.SizeBytes.
+func (s *SignalStack) SizeBytes() int {
+    return 24
+}
+
+// MarshalBytes implements marshal.Marshallable.MarshalBytes.
+func (s *SignalStack) MarshalBytes(dst []byte) {
+    usermem.ByteOrder.PutUint64(dst[:8], uint64(s.Addr))
+    dst = dst[8:]
+    usermem.ByteOrder.PutUint32(dst[:4], uint32(s.Flags))
+    dst = dst[4:]
+    // Padding: dst[:sizeof(uint32)] ~= uint32(0)
+    dst = dst[4:]
+    usermem.ByteOrder.PutUint64(dst[:8], uint64(s.Size))
+    dst = dst[8:]
+}
+
+// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
+func (s *SignalStack) UnmarshalBytes(src []byte) {
+    s.Addr = uint64(usermem.ByteOrder.Uint64(src[:8]))
+    src = src[8:]
+    s.Flags = uint32(usermem.ByteOrder.Uint32(src[:4]))
+    src = src[4:]
+    // Padding: var _ uint32 ~= src[:sizeof(uint32)]
+    src = src[4:]
+    s.Size = uint64(usermem.ByteOrder.Uint64(src[:8]))
+    src = src[8:]
+}
+
+// Packed implements marshal.Marshallable.Packed.
+//go:nosplit
+func (s *SignalStack) Packed() bool {
+    return true
+}
+
+// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
+func (s *SignalStack) MarshalUnsafe(dst []byte) {
+    safecopy.CopyIn(dst, unsafe.Pointer(s))
+}
+
+// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
+func (s *SignalStack) UnmarshalUnsafe(src []byte) {
+    safecopy.CopyOut(unsafe.Pointer(s), src)
+}
+
+// CopyOutN implements marshal.Marshallable.CopyOutN.
+//go:nosplit
+func (s *SignalStack) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := task.CopyOutBytes(addr, buf[:limit]) // escapes: okay.
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return length, err
+}
+
+// CopyOut implements marshal.Marshallable.CopyOut.
+//go:nosplit
+func (s *SignalStack) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
+    return s.CopyOutN(task, addr, s.SizeBytes())
+}
+
+// CopyIn implements marshal.Marshallable.CopyIn.
+//go:nosplit
+func (s *SignalStack) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := task.CopyInBytes(addr, buf) // escapes: okay.
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return length, err
+}
+
+// WriteTo implements io.WriterTo.WriteTo.
+func (s *SignalStack) WriteTo(w io.Writer) (int64, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := w.Write(buf)
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return int64(length), err
+}
+
+// SizeBytes implements marshal.Marshallable.SizeBytes.
+func (s *SignalInfo) SizeBytes() int {
+    return 16 +
+        1*(128-16)
+}
+
+// MarshalBytes implements marshal.Marshallable.MarshalBytes.
+func (s *SignalInfo) MarshalBytes(dst []byte) {
+    usermem.ByteOrder.PutUint32(dst[:4], uint32(s.Signo))
+    dst = dst[4:]
+    usermem.ByteOrder.PutUint32(dst[:4], uint32(s.Errno))
+    dst = dst[4:]
+    usermem.ByteOrder.PutUint32(dst[:4], uint32(s.Code))
+    dst = dst[4:]
+    // Padding: dst[:sizeof(uint32)] ~= uint32(0)
+    dst = dst[4:]
+    for idx := 0; idx < (128-16); idx++ {
+        dst[0] = byte(s.Fields[idx])
+        dst = dst[1:]
+    }
+}
+
+// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
+func (s *SignalInfo) UnmarshalBytes(src []byte) {
+    s.Signo = int32(usermem.ByteOrder.Uint32(src[:4]))
+    src = src[4:]
+    s.Errno = int32(usermem.ByteOrder.Uint32(src[:4]))
+    src = src[4:]
+    s.Code = int32(usermem.ByteOrder.Uint32(src[:4]))
+    src = src[4:]
+    // Padding: var _ uint32 ~= src[:sizeof(uint32)]
+    src = src[4:]
+    for idx := 0; idx < (128-16); idx++ {
+        s.Fields[idx] = src[0]
+        src = src[1:]
+    }
+}
+
+// Packed implements marshal.Marshallable.Packed.
+//go:nosplit
+func (s *SignalInfo) Packed() bool {
+    return true
+}
+
+// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
+func (s *SignalInfo) MarshalUnsafe(dst []byte) {
+    safecopy.CopyIn(dst, unsafe.Pointer(s))
+}
+
+// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
+func (s *SignalInfo) UnmarshalUnsafe(src []byte) {
+    safecopy.CopyOut(unsafe.Pointer(s), src)
+}
+
+// CopyOutN implements marshal.Marshallable.CopyOutN.
+//go:nosplit
+func (s *SignalInfo) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := task.CopyOutBytes(addr, buf[:limit]) // escapes: okay.
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return length, err
+}
+
+// CopyOut implements marshal.Marshallable.CopyOut.
+//go:nosplit
+func (s *SignalInfo) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
+    return s.CopyOutN(task, addr, s.SizeBytes())
+}
+
+// CopyIn implements marshal.Marshallable.CopyIn.
+//go:nosplit
+func (s *SignalInfo) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := task.CopyInBytes(addr, buf) // escapes: okay.
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return length, err
+}
+
+// WriteTo implements io.WriterTo.WriteTo.
+func (s *SignalInfo) WriteTo(w io.Writer) (int64, error) {
+    // Construct a slice backed by dst's underlying memory.
+    var buf []byte
+    hdr := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
+    hdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(s)))
+    hdr.Len = s.SizeBytes()
+    hdr.Cap = s.SizeBytes()
+
+    length, err := w.Write(buf)
+    // Since we bypassed the compiler's escape analysis, indicate that s
+    // must live until the use above.
+    runtime.KeepAlive(s)
+    return int64(length), err
+}
+
diff --git a/pkg/sentry/arch/arch_amd64.go b/pkg/sentry/arch/arch_amd64.go
index 85d6acc0f..3b3a0a272 100644
--- a/pkg/sentry/arch/arch_amd64.go
+++ b/pkg/sentry/arch/arch_amd64.go
@@ -22,7 +22,6 @@ import (
 	"math/rand"
 	"syscall"
 
-	"gvisor.dev/gvisor/pkg/binary"
 	"gvisor.dev/gvisor/pkg/cpuid"
 	"gvisor.dev/gvisor/pkg/sentry/limits"
 	"gvisor.dev/gvisor/pkg/usermem"
@@ -301,8 +300,10 @@ func (c *context64) PtracePeekUser(addr uintptr) (interface{}, error) {
 	// PTRACE_PEEKUSER and PTRACE_POKEUSER are only effective on regs and
 	// u_debugreg, returning 0 or silently no-oping for other fields
 	// respectively.
-	if addr < uintptr(ptraceRegsSize) {
-		buf := binary.Marshal(nil, usermem.ByteOrder, c.ptraceGetRegs())
+	if addr < uintptr(registersSize) {
+		regs := c.ptraceGetRegs()
+		buf := make([]byte, regs.SizeBytes())
+		regs.MarshalUnsafe(buf)
 		return c.Native(uintptr(usermem.ByteOrder.Uint64(buf[addr:]))), nil
 	}
 	// Note: x86 debug registers are missing.
@@ -314,8 +315,10 @@ func (c *context64) PtracePokeUser(addr, data uintptr) error {
 	if addr&7 != 0 || addr >= userStructSize {
 		return syscall.EIO
 	}
-	if addr < uintptr(ptraceRegsSize) {
-		buf := binary.Marshal(nil, usermem.ByteOrder, c.ptraceGetRegs())
+	if addr < uintptr(registersSize) {
+		regs := c.ptraceGetRegs()
+		buf := make([]byte, regs.SizeBytes())
+		regs.MarshalUnsafe(buf)
 		usermem.ByteOrder.PutUint64(buf[addr:], uint64(data))
 		_, err := c.PtraceSetRegs(bytes.NewBuffer(buf))
 		return err
diff --git a/pkg/sentry/arch/arch_amd64_abi_autogen_unsafe.go b/pkg/sentry/arch/arch_amd64_abi_autogen_unsafe.go
new file mode 100755
index 000000000..8eadb6e22
--- /dev/null
+++ b/pkg/sentry/arch/arch_amd64_abi_autogen_unsafe.go
@@ -0,0 +1,11 @@
+// Automatically generated marshal implementation. See tools/go_marshal.
+
+// +build amd64
+// +build amd64
+// +build amd64
+
+package arch
+
+import (
+)
+
diff --git a/pkg/sentry/arch/arch_arm64.go b/pkg/sentry/arch/arch_arm64.go
index db99c5acb..ada7ac7b8 100755
--- a/pkg/sentry/arch/arch_arm64.go
+++ b/pkg/sentry/arch/arch_arm64.go
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// +build arm64
+
 package arch
 
 import (
diff --git a/pkg/sentry/arch/arch_arm64_abi_autogen_unsafe.go b/pkg/sentry/arch/arch_arm64_abi_autogen_unsafe.go
new file mode 100755
index 000000000..c8e4c7c24
--- /dev/null
+++ b/pkg/sentry/arch/arch_arm64_abi_autogen_unsafe.go
@@ -0,0 +1,10 @@
+// Automatically generated marshal implementation. See tools/go_marshal.
+
+// +build arm64
+// +build arm64
+
+package arch
+
+import (
+)
+
diff --git a/pkg/sentry/arch/arch_arm64_state_autogen.go b/pkg/sentry/arch/arch_arm64_state_autogen.go
index 49f2e3d67..9c6dfdf2e 100755
--- a/pkg/sentry/arch/arch_arm64_state_autogen.go
+++ b/pkg/sentry/arch/arch_arm64_state_autogen.go
@@ -1,5 +1,6 @@
 // automatically generated by stateify.
 
 // +build arm64
+// +build arm64
 
 package arch
diff --git a/pkg/sentry/arch/arch_impl_abi_autogen_unsafe.go b/pkg/sentry/arch/arch_impl_abi_autogen_unsafe.go
new file mode 100755
index 000000000..4357dc093
--- /dev/null
+++ b/pkg/sentry/arch/arch_impl_abi_autogen_unsafe.go
@@ -0,0 +1,9 @@
+// Automatically generated marshal implementation. See tools/go_marshal.
+
+// +build amd64 386
+
+package arch
+
+import (
+)
+
diff --git a/pkg/sentry/arch/arch_impl_state_autogen.go b/pkg/sentry/arch/arch_impl_state_autogen.go
index 55721c710..7303bb17f 100755
--- a/pkg/sentry/arch/arch_impl_state_autogen.go
+++ b/pkg/sentry/arch/arch_impl_state_autogen.go
@@ -11,16 +11,15 @@ import (
 func (x *State) beforeSave() {}
 func (x *State) save(m state.Map) {
 	x.beforeSave()
-	var Regs syscallPtraceRegs = x.saveRegs()
-	m.SaveValue("Regs", Regs)
+	m.Save("Regs", &x.Regs)
 	m.Save("x86FPState", &x.x86FPState)
 	m.Save("FeatureSet", &x.FeatureSet)
 }
 
 func (x *State) load(m state.Map) {
+	m.Load("Regs", &x.Regs)
 	m.LoadWait("x86FPState", &x.x86FPState)
 	m.Load("FeatureSet", &x.FeatureSet)
-	m.LoadValue("Regs", new(syscallPtraceRegs), func(y interface{}) { x.loadRegs(y.(syscallPtraceRegs)) })
 	m.AfterLoad(x.afterLoad)
 }
 
diff --git a/pkg/sentry/arch/arch_state_aarch64.go b/pkg/sentry/arch/arch_state_aarch64.go
deleted file mode 100755
index 0136a85ad..000000000
--- a/pkg/sentry/arch/arch_state_aarch64.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2020 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 arm64
-
-package arch
-
-import (
-	"syscall"
-)
-
-type syscallPtraceRegs struct {
-	Regs   [31]uint64
-	Sp     uint64
-	Pc     uint64
-	Pstate uint64
-}
-
-// saveRegs is invoked by stateify.
-func (s *State) saveRegs() syscallPtraceRegs {
-	return syscallPtraceRegs(s.Regs)
-}
-
-// loadRegs is invoked by stateify.
-func (s *State) loadRegs(r syscallPtraceRegs) {
-	s.Regs = syscall.PtraceRegs(r)
-}
diff --git a/pkg/sentry/arch/arch_state_autogen.go b/pkg/sentry/arch/arch_state_autogen.go
index 1bcc94438..bb4bcda4b 100755
--- a/pkg/sentry/arch/arch_state_autogen.go
+++ b/pkg/sentry/arch/arch_state_autogen.go
@@ -31,69 +31,6 @@ func (x *MmapLayout) load(m state.Map) {
 	m.Load("MaxStackRand", &x.MaxStackRand)
 }
 
-func (x *syscallPtraceRegs) beforeSave() {}
-func (x *syscallPtraceRegs) save(m state.Map) {
-	x.beforeSave()
-	m.Save("R15", &x.R15)
-	m.Save("R14", &x.R14)
-	m.Save("R13", &x.R13)
-	m.Save("R12", &x.R12)
-	m.Save("Rbp", &x.Rbp)
-	m.Save("Rbx", &x.Rbx)
-	m.Save("R11", &x.R11)
-	m.Save("R10", &x.R10)
-	m.Save("R9", &x.R9)
-	m.Save("R8", &x.R8)
-	m.Save("Rax", &x.Rax)
-	m.Save("Rcx", &x.Rcx)
-	m.Save("Rdx", &x.Rdx)
-	m.Save("Rsi", &x.Rsi)
-	m.Save("Rdi", &x.Rdi)
-	m.Save("Orig_rax", &x.Orig_rax)
-	m.Save("Rip", &x.Rip)
-	m.Save("Cs", &x.Cs)
-	m.Save("Eflags", &x.Eflags)
-	m.Save("Rsp", &x.Rsp)
-	m.Save("Ss", &x.Ss)
-	m.Save("Fs_base", &x.Fs_base)
-	m.Save("Gs_base", &x.Gs_base)
-	m.Save("Ds", &x.Ds)
-	m.Save("Es", &x.Es)
-	m.Save("Fs", &x.Fs)
-	m.Save("Gs", &x.Gs)
-}
-
-func (x *syscallPtraceRegs) afterLoad() {}
-func (x *syscallPtraceRegs) load(m state.Map) {
-	m.Load("R15", &x.R15)
-	m.Load("R14", &x.R14)
-	m.Load("R13", &x.R13)
-	m.Load("R12", &x.R12)
-	m.Load("Rbp", &x.Rbp)
-	m.Load("Rbx", &x.Rbx)
-	m.Load("R11", &x.R11)
-	m.Load("R10", &x.R10)
-	m.Load("R9", &x.R9)
-	m.Load("R8", &x.R8)
-	m.Load("Rax", &x.Rax)
-	m.Load("Rcx", &x.Rcx)
-	m.Load("Rdx", &x.Rdx)
-	m.Load("Rsi", &x.Rsi)
-	m.Load("Rdi", &x.Rdi)
-	m.Load("Orig_rax", &x.Orig_rax)
-	m.Load("Rip", &x.Rip)
-	m.Load("Cs", &x.Cs)
-	m.Load("Eflags", &x.Eflags)
-	m.Load("Rsp", &x.Rsp)
-	m.Load("Ss", &x.Ss)
-	m.Load("Fs_base", &x.Fs_base)
-	m.Load("Gs_base", &x.Gs_base)
-	m.Load("Ds", &x.Ds)
-	m.Load("Es", &x.Es)
-	m.Load("Fs", &x.Fs)
-	m.Load("Gs", &x.Gs)
-}
-
 func (x *AuxEntry) beforeSave() {}
 func (x *AuxEntry) save(m state.Map) {
 	x.beforeSave()
@@ -158,7 +95,6 @@ func (x *SignalInfo) load(m state.Map) {
 
 func init() {
 	state.Register("pkg/sentry/arch.MmapLayout", (*MmapLayout)(nil), state.Fns{Save: (*MmapLayout).save, Load: (*MmapLayout).load})
-	state.Register("pkg/sentry/arch.syscallPtraceRegs", (*syscallPtraceRegs)(nil), state.Fns{Save: (*syscallPtraceRegs).save, Load: (*syscallPtraceRegs).load})
 	state.Register("pkg/sentry/arch.AuxEntry", (*AuxEntry)(nil), state.Fns{Save: (*AuxEntry).save, Load: (*AuxEntry).load})
 	state.Register("pkg/sentry/arch.SignalAct", (*SignalAct)(nil), state.Fns{Save: (*SignalAct).save, Load: (*SignalAct).load})
 	state.Register("pkg/sentry/arch.SignalStack", (*SignalStack)(nil), state.Fns{Save: (*SignalStack).save, Load: (*SignalStack).load})
diff --git a/pkg/sentry/arch/arch_state_x86.go b/pkg/sentry/arch/arch_state_x86.go
index aa31169e0..19ce99d25 100644
--- a/pkg/sentry/arch/arch_state_x86.go
+++ b/pkg/sentry/arch/arch_state_x86.go
@@ -18,7 +18,6 @@ package arch
 
 import (
 	"fmt"
-	"syscall"
 
 	"gvisor.dev/gvisor/pkg/cpuid"
 	"gvisor.dev/gvisor/pkg/usermem"
@@ -90,44 +89,3 @@ func (s *State) afterLoadFPState() {
 	// Copy to the new, aligned location.
 	copy(s.x86FPState, old)
 }
-
-// +stateify savable
-type syscallPtraceRegs struct {
-	R15      uint64
-	R14      uint64
-	R13      uint64
-	R12      uint64
-	Rbp      uint64
-	Rbx      uint64
-	R11      uint64
-	R10      uint64
-	R9       uint64
-	R8       uint64
-	Rax      uint64
-	Rcx      uint64
-	Rdx      uint64
-	Rsi      uint64
-	Rdi      uint64
-	Orig_rax uint64
-	Rip      uint64
-	Cs       uint64
-	Eflags   uint64
-	Rsp      uint64
-	Ss       uint64
-	Fs_base  uint64
-	Gs_base  uint64
-	Ds       uint64
-	Es       uint64
-	Fs       uint64
-	Gs       uint64
-}
-
-// saveRegs is invoked by stateify.
-func (s *State) saveRegs() syscallPtraceRegs {
-	return syscallPtraceRegs(s.Regs)
-}
-
-// loadRegs is invoked by stateify.
-func (s *State) loadRegs(r syscallPtraceRegs) {
-	s.Regs = syscall.PtraceRegs(r)
-}
diff --git a/pkg/sentry/arch/arch_x86.go b/pkg/sentry/arch/arch_x86.go
index 7fc4c0473..dc458b37f 100644
--- a/pkg/sentry/arch/arch_x86.go
+++ b/pkg/sentry/arch/arch_x86.go
@@ -21,7 +21,7 @@ import (
 	"io"
 	"syscall"
 
-	"gvisor.dev/gvisor/pkg/binary"
+	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/cpuid"
 	"gvisor.dev/gvisor/pkg/log"
 	rpb "gvisor.dev/gvisor/pkg/sentry/arch/registers_go_proto"
@@ -30,6 +30,9 @@ import (
 	"gvisor.dev/gvisor/pkg/usermem"
 )
 
+// Registers represents the CPU registers for this architecture.
+type Registers = linux.PtraceRegs
+
 // System-related constants for x86.
 const (
 	// SyscallWidth is the width of syscall, sysenter, and int 80 insturctions.
@@ -267,10 +270,12 @@ func (s *State) RegisterMap() (map[string]uintptr, error) {
 
 // PtraceGetRegs implements Context.PtraceGetRegs.
 func (s *State) PtraceGetRegs(dst io.Writer) (int, error) {
-	return dst.Write(binary.Marshal(nil, usermem.ByteOrder, s.ptraceGetRegs()))
+	regs := s.ptraceGetRegs()
+	n, err := regs.WriteTo(dst)
+	return int(n), err
 }
 
-func (s *State) ptraceGetRegs() syscall.PtraceRegs {
+func (s *State) ptraceGetRegs() Registers {
 	regs := s.Regs
 	// These may not be initialized.
 	if regs.Cs == 0 || regs.Ss == 0 || regs.Eflags == 0 {
@@ -306,16 +311,16 @@ func (s *State) ptraceGetRegs() syscall.PtraceRegs {
 	return regs
 }
 
-var ptraceRegsSize = int(binary.Size(syscall.PtraceRegs{}))
+var registersSize = (*Registers)(nil).SizeBytes()
 
 // PtraceSetRegs implements Context.PtraceSetRegs.
 func (s *State) PtraceSetRegs(src io.Reader) (int, error) {
-	var regs syscall.PtraceRegs
-	buf := make([]byte, ptraceRegsSize)
+	var regs Registers
+	buf := make([]byte, registersSize)
 	if _, err := io.ReadFull(src, buf); err != nil {
 		return 0, err
 	}
-	binary.Unmarshal(buf, usermem.ByteOrder, &regs)
+	regs.UnmarshalUnsafe(buf)
 	// Truncate segment registers to 16 bits.
 	regs.Cs = uint64(uint16(regs.Cs))
 	regs.Ds = uint64(uint16(regs.Ds))
@@ -369,7 +374,7 @@ func (s *State) PtraceSetRegs(src io.Reader) (int, error) {
 	}
 	regs.Eflags = (s.Regs.Eflags &^ eflagsPtraceMutable) | (regs.Eflags & eflagsPtraceMutable)
 	s.Regs = regs
-	return ptraceRegsSize, nil
+	return registersSize, nil
 }
 
 // isUserSegmentSelector returns true if the given segment selector specifies a
@@ -538,7 +543,7 @@ const (
 func (s *State) PtraceGetRegSet(regset uintptr, dst io.Writer, maxlen int) (int, error) {
 	switch regset {
 	case _NT_PRSTATUS:
-		if maxlen < ptraceRegsSize {
+		if maxlen < registersSize {
 			return 0, syserror.EFAULT
 		}
 		return s.PtraceGetRegs(dst)
@@ -558,7 +563,7 @@ func (s *State) PtraceGetRegSet(regset uintptr, dst io.Writer, maxlen int) (int,
 func (s *State) PtraceSetRegSet(regset uintptr, src io.Reader, maxlen int) (int, error) {
 	switch regset {
 	case _NT_PRSTATUS:
-		if maxlen < ptraceRegsSize {
+		if maxlen < registersSize {
 			return 0, syserror.EFAULT
 		}
 		return s.PtraceSetRegs(src)
diff --git a/pkg/sentry/arch/arch_x86_impl.go b/pkg/sentry/arch/arch_x86_impl.go
index 3edf40764..0c73fcbfb 100755
--- a/pkg/sentry/arch/arch_x86_impl.go
+++ b/pkg/sentry/arch/arch_x86_impl.go
@@ -17,8 +17,6 @@
 package arch
 
 import (
-	"syscall"
-
 	"gvisor.dev/gvisor/pkg/cpuid"
 )
 
@@ -28,7 +26,7 @@ import (
 // +stateify savable
 type State struct {
 	// The system registers.
-	Regs syscall.PtraceRegs `state:".(syscallPtraceRegs)"`
+	Regs Registers
 
 	// Our floating point state.
 	x86FPState `state:"wait"`
diff --git a/pkg/sentry/arch/signal.go b/pkg/sentry/arch/signal.go
index 8b03d0187..c9fb55d00 100755
--- a/pkg/sentry/arch/signal.go
+++ b/pkg/sentry/arch/signal.go
@@ -22,6 +22,7 @@ import (
 // SignalAct represents the action that should be taken when a signal is
 // delivered, and is equivalent to struct sigaction.
 //
+// +marshal
 // +stateify savable
 type SignalAct struct {
 	Handler  uint64
@@ -43,6 +44,7 @@ func (s *SignalAct) DeserializeTo(other *SignalAct) {
 // SignalStack represents information about a user stack, and is equivalent to
 // stack_t.
 //
+// +marshal
 // +stateify savable
 type SignalStack struct {
 	Addr  uint64
@@ -64,6 +66,7 @@ func (s *SignalStack) DeserializeTo(other *SignalStack) {
 // SignalInfo represents information about a signal being delivered, and is
 // equivalent to struct siginfo in linux kernel(linux/include/uapi/asm-generic/siginfo.h).
 //
+// +marshal
 // +stateify savable
 type SignalInfo struct {
 	Signo int32 // Signal number
diff --git a/pkg/sentry/arch/signal_act.go b/pkg/sentry/arch/signal_act.go
index f9ca2e74e..32173aa20 100644
--- a/pkg/sentry/arch/signal_act.go
+++ b/pkg/sentry/arch/signal_act.go
@@ -14,6 +14,8 @@
 
 package arch
 
+import "gvisor.dev/gvisor/tools/go_marshal/marshal"
+
 // Special values for SignalAct.Handler.
 const (
 	// SignalActDefault is SIG_DFL and specifies that the default behavior for
@@ -71,6 +73,8 @@ func (s SignalAct) HasRestorer() bool {
 // NativeSignalAct is a type that is equivalent to struct sigaction in the
 // guest architecture.
 type NativeSignalAct interface {
+	marshal.Marshallable
+
 	// SerializeFrom copies the data in the host SignalAct s into this object.
 	SerializeFrom(s *SignalAct)
 
diff --git a/pkg/sentry/arch/signal_stack.go b/pkg/sentry/arch/signal_stack.go
index e58f055c7..0fa738a1d 100644
--- a/pkg/sentry/arch/signal_stack.go
+++ b/pkg/sentry/arch/signal_stack.go
@@ -18,6 +18,7 @@ package arch
 
 import (
 	"gvisor.dev/gvisor/pkg/usermem"
+	"gvisor.dev/gvisor/tools/go_marshal/marshal"
 )
 
 const (
@@ -55,6 +56,8 @@ func (s *SignalStack) Contains(sp usermem.Addr) bool {
 // NativeSignalStack is a type that is equivalent to stack_t in the guest
 // architecture.
 type NativeSignalStack interface {
+	marshal.Marshallable
+
 	// SerializeFrom copies the data in the host SignalStack s into this
 	// object.
 	SerializeFrom(s *SignalStack)
diff --git a/pkg/sentry/kernel/task_signals.go b/pkg/sentry/kernel/task_signals.go
index 7d25e98f7..79766cafe 100644
--- a/pkg/sentry/kernel/task_signals.go
+++ b/pkg/sentry/kernel/task_signals.go
@@ -716,7 +716,7 @@ func (tg *ThreadGroup) SetSignalAct(sig linux.Signal, actptr *arch.SignalAct) (a
 func (t *Task) CopyOutSignalAct(addr usermem.Addr, s *arch.SignalAct) error {
 	n := t.Arch().NewSignalAct()
 	n.SerializeFrom(s)
-	_, err := t.CopyOut(addr, n)
+	_, err := n.CopyOut(t, addr)
 	return err
 }
 
@@ -725,7 +725,7 @@ func (t *Task) CopyOutSignalAct(addr usermem.Addr, s *arch.SignalAct) error {
 func (t *Task) CopyInSignalAct(addr usermem.Addr) (arch.SignalAct, error) {
 	n := t.Arch().NewSignalAct()
 	var s arch.SignalAct
-	if _, err := t.CopyIn(addr, n); err != nil {
+	if _, err := n.CopyIn(t, addr); err != nil {
 		return s, err
 	}
 	n.DeserializeTo(&s)
@@ -737,7 +737,7 @@ func (t *Task) CopyInSignalAct(addr usermem.Addr) (arch.SignalAct, error) {
 func (t *Task) CopyOutSignalStack(addr usermem.Addr, s *arch.SignalStack) error {
 	n := t.Arch().NewSignalStack()
 	n.SerializeFrom(s)
-	_, err := t.CopyOut(addr, n)
+	_, err := n.CopyOut(t, addr)
 	return err
 }
 
@@ -746,7 +746,7 @@ func (t *Task) CopyOutSignalStack(addr usermem.Addr, s *arch.SignalStack) error
 func (t *Task) CopyInSignalStack(addr usermem.Addr) (arch.SignalStack, error) {
 	n := t.Arch().NewSignalStack()
 	var s arch.SignalStack
-	if _, err := t.CopyIn(addr, n); err != nil {
+	if _, err := n.CopyIn(t, addr); err != nil {
 		return s, err
 	}
 	n.DeserializeTo(&s)
diff --git a/pkg/sentry/platform/kvm/kvm_arm64.go b/pkg/sentry/platform/kvm/kvm_arm64.go
index 716198712..29d457a7e 100755
--- a/pkg/sentry/platform/kvm/kvm_arm64.go
+++ b/pkg/sentry/platform/kvm/kvm_arm64.go
@@ -17,8 +17,7 @@
 package kvm
 
 import (
-	"syscall"
-
+	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/platform/ring0"
 )
 
@@ -37,7 +36,7 @@ type userFpsimdState struct {
 }
 
 type userRegs struct {
-	Regs    syscall.PtraceRegs
+	Regs    arch.Registers
 	sp_el1  uint64
 	elr_el1 uint64
 	spsr    [KVM_NR_SPSR]uint64
diff --git a/pkg/sentry/platform/ptrace/ptrace_amd64.go b/pkg/sentry/platform/ptrace/ptrace_amd64.go
index 24fc5dc62..3b9a870a5 100644
--- a/pkg/sentry/platform/ptrace/ptrace_amd64.go
+++ b/pkg/sentry/platform/ptrace/ptrace_amd64.go
@@ -15,9 +15,8 @@
 package ptrace
 
 import (
-	"syscall"
-
 	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/arch"
 )
 
 // fpRegSet returns the GETREGSET/SETREGSET register set type to be used.
@@ -28,12 +27,12 @@ func fpRegSet(useXsave bool) uintptr {
 	return linux.NT_PRFPREG
 }
 
-func stackPointer(r *syscall.PtraceRegs) uintptr {
+func stackPointer(r *arch.Registers) uintptr {
 	return uintptr(r.Rsp)
 }
 
 // x86 use the fs_base register to store the TLS pointer which can be
-// get/set in "func (t *thread) get/setRegs(regs *syscall.PtraceRegs)".
+// get/set in "func (t *thread) get/setRegs(regs *arch.Registers)".
 // So both of the get/setTLS() operations are noop here.
 
 // getTLS gets the thread local storage register.
diff --git a/pkg/sentry/platform/ptrace/ptrace_arm64.go b/pkg/sentry/platform/ptrace/ptrace_arm64.go
index 4db28c534..5c869926a 100644
--- a/pkg/sentry/platform/ptrace/ptrace_arm64.go
+++ b/pkg/sentry/platform/ptrace/ptrace_arm64.go
@@ -15,9 +15,8 @@
 package ptrace
 
 import (
-	"syscall"
-
 	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/arch"
 )
 
 // fpRegSet returns the GETREGSET/SETREGSET register set type to be used.
@@ -25,6 +24,6 @@ func fpRegSet(_ bool) uintptr {
 	return linux.NT_PRFPREG
 }
 
-func stackPointer(r *syscall.PtraceRegs) uintptr {
+func stackPointer(r *arch.Registers) uintptr {
 	return uintptr(r.Sp)
 }
diff --git a/pkg/sentry/platform/ptrace/ptrace_unsafe.go b/pkg/sentry/platform/ptrace/ptrace_unsafe.go
index 6c0ed7b3e..8b72d24e8 100644
--- a/pkg/sentry/platform/ptrace/ptrace_unsafe.go
+++ b/pkg/sentry/platform/ptrace/ptrace_unsafe.go
@@ -24,7 +24,7 @@ import (
 )
 
 // getRegs gets the general purpose register set.
-func (t *thread) getRegs(regs *syscall.PtraceRegs) error {
+func (t *thread) getRegs(regs *arch.Registers) error {
 	iovec := syscall.Iovec{
 		Base: (*byte)(unsafe.Pointer(regs)),
 		Len:  uint64(unsafe.Sizeof(*regs)),
@@ -43,7 +43,7 @@ func (t *thread) getRegs(regs *syscall.PtraceRegs) error {
 }
 
 // setRegs sets the general purpose register set.
-func (t *thread) setRegs(regs *syscall.PtraceRegs) error {
+func (t *thread) setRegs(regs *arch.Registers) error {
 	iovec := syscall.Iovec{
 		Base: (*byte)(unsafe.Pointer(regs)),
 		Len:  uint64(unsafe.Sizeof(*regs)),
diff --git a/pkg/sentry/platform/ptrace/subprocess.go b/pkg/sentry/platform/ptrace/subprocess.go
index 773ddb1ed..2389423b0 100644
--- a/pkg/sentry/platform/ptrace/subprocess.go
+++ b/pkg/sentry/platform/ptrace/subprocess.go
@@ -63,7 +63,7 @@ type thread struct {
 	// initRegs are the initial registers for the first thread.
 	//
 	// These are used for the register set for system calls.
-	initRegs syscall.PtraceRegs
+	initRegs arch.Registers
 }
 
 // threadPool is a collection of threads.
@@ -317,7 +317,7 @@ const (
 )
 
 func (t *thread) dumpAndPanic(message string) {
-	var regs syscall.PtraceRegs
+	var regs arch.Registers
 	message += "\n"
 	if err := t.getRegs(&regs); err == nil {
 		message += dumpRegs(&regs)
@@ -423,7 +423,7 @@ func (t *thread) init() {
 // This is _not_ for use by application system calls, rather it is for use when
 // a system call must be injected into the remote context (e.g. mmap, munmap).
 // Note that clones are handled separately.
-func (t *thread) syscall(regs *syscall.PtraceRegs) (uintptr, error) {
+func (t *thread) syscall(regs *arch.Registers) (uintptr, error) {
 	// Set registers.
 	if err := t.setRegs(regs); err != nil {
 		panic(fmt.Sprintf("ptrace set regs failed: %v", err))
@@ -461,7 +461,7 @@ func (t *thread) syscall(regs *syscall.PtraceRegs) (uintptr, error) {
 // syscallIgnoreInterrupt ignores interrupts on the system call thread and
 // restarts the syscall if the kernel indicates that should happen.
 func (t *thread) syscallIgnoreInterrupt(
-	initRegs *syscall.PtraceRegs,
+	initRegs *arch.Registers,
 	sysno uintptr,
 	args ...arch.SyscallArgument) (uintptr, error) {
 	for {
diff --git a/pkg/sentry/platform/ptrace/subprocess_amd64.go b/pkg/sentry/platform/ptrace/subprocess_amd64.go
index cd74945e7..84b699f0d 100644
--- a/pkg/sentry/platform/ptrace/subprocess_amd64.go
+++ b/pkg/sentry/platform/ptrace/subprocess_amd64.go
@@ -41,7 +41,7 @@ const (
 // resetSysemuRegs sets up emulation registers.
 //
 // This should be called prior to calling sysemu.
-func (t *thread) resetSysemuRegs(regs *syscall.PtraceRegs) {
+func (t *thread) resetSysemuRegs(regs *arch.Registers) {
 	regs.Cs = t.initRegs.Cs
 	regs.Ss = t.initRegs.Ss
 	regs.Ds = t.initRegs.Ds
@@ -53,7 +53,7 @@ func (t *thread) resetSysemuRegs(regs *syscall.PtraceRegs) {
 // createSyscallRegs sets up syscall registers.
 //
 // This should be called to generate registers for a system call.
-func createSyscallRegs(initRegs *syscall.PtraceRegs, sysno uintptr, args ...arch.SyscallArgument) syscall.PtraceRegs {
+func createSyscallRegs(initRegs *arch.Registers, sysno uintptr, args ...arch.SyscallArgument) arch.Registers {
 	// Copy initial registers.
 	regs := *initRegs
 
@@ -82,18 +82,18 @@ func createSyscallRegs(initRegs *syscall.PtraceRegs, sysno uintptr, args ...arch
 }
 
 // isSingleStepping determines if the registers indicate single-stepping.
-func isSingleStepping(regs *syscall.PtraceRegs) bool {
+func isSingleStepping(regs *arch.Registers) bool {
 	return (regs.Eflags & arch.X86TrapFlag) != 0
 }
 
 // updateSyscallRegs updates registers after finishing sysemu.
-func updateSyscallRegs(regs *syscall.PtraceRegs) {
+func updateSyscallRegs(regs *arch.Registers) {
 	// Ptrace puts -ENOSYS in rax on syscall-enter-stop.
 	regs.Rax = regs.Orig_rax
 }
 
 // syscallReturnValue extracts a sensible return from registers.
-func syscallReturnValue(regs *syscall.PtraceRegs) (uintptr, error) {
+func syscallReturnValue(regs *arch.Registers) (uintptr, error) {
 	rval := int64(regs.Rax)
 	if rval < 0 {
 		return 0, syscall.Errno(-rval)
@@ -101,7 +101,7 @@ func syscallReturnValue(regs *syscall.PtraceRegs) (uintptr, error) {
 	return uintptr(rval), nil
 }
 
-func dumpRegs(regs *syscall.PtraceRegs) string {
+func dumpRegs(regs *arch.Registers) string {
 	var m strings.Builder
 
 	fmt.Fprintf(&m, "Registers:\n")
@@ -143,7 +143,7 @@ func (t *thread) adjustInitRegsRip() {
 }
 
 // Pass the expected PPID to the child via R15 when creating stub process.
-func initChildProcessPPID(initregs *syscall.PtraceRegs, ppid int32) {
+func initChildProcessPPID(initregs *arch.Registers, ppid int32) {
 	initregs.R15 = uint64(ppid)
 	// Rbx has to be set to 1 when creating stub process.
 	initregs.Rbx = 1
@@ -156,7 +156,7 @@ func initChildProcessPPID(initregs *syscall.PtraceRegs, ppid int32) {
 //
 // Note that this should only be called after verifying that the signalInfo has
 // been generated by the kernel.
-func patchSignalInfo(regs *syscall.PtraceRegs, signalInfo *arch.SignalInfo) {
+func patchSignalInfo(regs *arch.Registers, signalInfo *arch.SignalInfo) {
 	if linux.Signal(signalInfo.Signo) == linux.SIGSYS {
 		signalInfo.Signo = int32(linux.SIGSEGV)
 
diff --git a/pkg/sentry/platform/ptrace/subprocess_arm64.go b/pkg/sentry/platform/ptrace/subprocess_arm64.go
index 7f5c393f0..bd618fae8 100644
--- a/pkg/sentry/platform/ptrace/subprocess_arm64.go
+++ b/pkg/sentry/platform/ptrace/subprocess_arm64.go
@@ -41,13 +41,13 @@ const (
 // resetSysemuRegs sets up emulation registers.
 //
 // This should be called prior to calling sysemu.
-func (t *thread) resetSysemuRegs(regs *syscall.PtraceRegs) {
+func (t *thread) resetSysemuRegs(regs *arch.Registers) {
 }
 
 // createSyscallRegs sets up syscall registers.
 //
 // This should be called to generate registers for a system call.
-func createSyscallRegs(initRegs *syscall.PtraceRegs, sysno uintptr, args ...arch.SyscallArgument) syscall.PtraceRegs {
+func createSyscallRegs(initRegs *arch.Registers, sysno uintptr, args ...arch.SyscallArgument) arch.Registers {
 	// Copy initial registers (Pc, Sp, etc.).
 	regs := *initRegs
 
@@ -78,7 +78,7 @@ func createSyscallRegs(initRegs *syscall.PtraceRegs, sysno uintptr, args ...arch
 }
 
 // isSingleStepping determines if the registers indicate single-stepping.
-func isSingleStepping(regs *syscall.PtraceRegs) bool {
+func isSingleStepping(regs *arch.Registers) bool {
 	// Refer to the ARM SDM D2.12.3: software step state machine
 	// return (regs.Pstate.SS == 1) && (MDSCR_EL1.SS == 1).
 	//
@@ -89,13 +89,13 @@ func isSingleStepping(regs *syscall.PtraceRegs) bool {
 }
 
 // updateSyscallRegs updates registers after finishing sysemu.
-func updateSyscallRegs(regs *syscall.PtraceRegs) {
+func updateSyscallRegs(regs *arch.Registers) {
 	// No special work is necessary.
 	return
 }
 
 // syscallReturnValue extracts a sensible return from registers.
-func syscallReturnValue(regs *syscall.PtraceRegs) (uintptr, error) {
+func syscallReturnValue(regs *arch.Registers) (uintptr, error) {
 	rval := int64(regs.Regs[0])
 	if rval < 0 {
 		return 0, syscall.Errno(-rval)
@@ -103,7 +103,7 @@ func syscallReturnValue(regs *syscall.PtraceRegs) (uintptr, error) {
 	return uintptr(rval), nil
 }
 
-func dumpRegs(regs *syscall.PtraceRegs) string {
+func dumpRegs(regs *arch.Registers) string {
 	var m strings.Builder
 
 	fmt.Fprintf(&m, "Registers:\n")
@@ -125,7 +125,7 @@ func (t *thread) adjustInitRegsRip() {
 }
 
 // Pass the expected PPID to the child via X7 when creating stub process
-func initChildProcessPPID(initregs *syscall.PtraceRegs, ppid int32) {
+func initChildProcessPPID(initregs *arch.Registers, ppid int32) {
 	initregs.Regs[7] = uint64(ppid)
 	// R9 has to be set to 1 when creating stub process.
 	initregs.Regs[9] = 1
@@ -138,7 +138,7 @@ func initChildProcessPPID(initregs *syscall.PtraceRegs, ppid int32) {
 //
 // Note that this should only be called after verifying that the signalInfo has
 // been generated by the kernel.
-func patchSignalInfo(regs *syscall.PtraceRegs, signalInfo *arch.SignalInfo) {
+func patchSignalInfo(regs *arch.Registers, signalInfo *arch.SignalInfo) {
 	if linux.Signal(signalInfo.Signo) == linux.SIGSYS {
 		signalInfo.Signo = int32(linux.SIGSEGV)
 
diff --git a/pkg/sentry/platform/ring0/defs_impl_amd64.go b/pkg/sentry/platform/ring0/defs_impl_amd64.go
index e96c62c76..029d699fe 100755
--- a/pkg/sentry/platform/ring0/defs_impl_amd64.go
+++ b/pkg/sentry/platform/ring0/defs_impl_amd64.go
@@ -1,14 +1,14 @@
 package ring0
 
 import (
-	"fmt"
 	"gvisor.dev/gvisor/pkg/cpuid"
+	"gvisor.dev/gvisor/pkg/sentry/arch"
+	"gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables"
+
+	"fmt"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"io"
 	"reflect"
-	"syscall"
-
-	"gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables"
 )
 
 // Kernel is a global kernel object.
@@ -63,7 +63,7 @@ type CPU struct {
 
 	// registers is a set of registers; these may be used on kernel system
 	// calls and exceptions via the Registers function.
-	registers syscall.PtraceRegs
+	registers arch.Registers
 
 	// hooks are kernel hooks.
 	hooks Hooks
@@ -74,14 +74,14 @@ type CPU struct {
 // This is explicitly safe to call during KernelException and KernelSyscall.
 //
 //go:nosplit
-func (c *CPU) Registers() *syscall.PtraceRegs {
+func (c *CPU) Registers() *arch.Registers {
 	return &c.registers
 }
 
 // SwitchOpts are passed to the Switch function.
 type SwitchOpts struct {
 	// Registers are the user register state.
-	Registers *syscall.PtraceRegs
+	Registers *arch.Registers
 
 	// FloatingPointState is a byte pointer where floating point state is
 	// saved and restored.
@@ -267,7 +267,7 @@ func Emit(w io.Writer) {
 	fmt.Fprintf(w, "#define SyscallInt80               0x%02x\n", SyscallInt80)
 	fmt.Fprintf(w, "#define Syscall                    0x%02x\n", Syscall)
 
-	p := &syscall.PtraceRegs{}
+	p := &arch.Registers{}
 	fmt.Fprintf(w, "\n// Ptrace registers.\n")
 	fmt.Fprintf(w, "#define PTRACE_R15      0x%02x\n", reflect.ValueOf(&p.R15).Pointer()-reflect.ValueOf(p).Pointer())
 	fmt.Fprintf(w, "#define PTRACE_R14      0x%02x\n", reflect.ValueOf(&p.R14).Pointer()-reflect.ValueOf(p).Pointer())
diff --git a/pkg/sentry/platform/ring0/defs_impl_arm64.go b/pkg/sentry/platform/ring0/defs_impl_arm64.go
index e29d62f04..93f23047d 100755
--- a/pkg/sentry/platform/ring0/defs_impl_arm64.go
+++ b/pkg/sentry/platform/ring0/defs_impl_arm64.go
@@ -1,13 +1,13 @@
 package ring0
 
 import (
-	"syscall"
-
 	"fmt"
+	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables"
-	"gvisor.dev/gvisor/pkg/usermem"
 	"io"
 	"reflect"
+
+	"gvisor.dev/gvisor/pkg/usermem"
 )
 
 // Useful bits.
@@ -155,7 +155,7 @@ type CPU struct {
 
 	// registers is a set of registers; these may be used on kernel system
 	// calls and exceptions via the Registers function.
-	registers syscall.PtraceRegs
+	registers arch.Registers
 
 	// hooks are kernel hooks.
 	hooks Hooks
@@ -166,14 +166,14 @@ type CPU struct {
 // This is explicitly safe to call during KernelException and KernelSyscall.
 //
 //go:nosplit
-func (c *CPU) Registers() *syscall.PtraceRegs {
+func (c *CPU) Registers() *arch.Registers {
 	return &c.registers
 }
 
 // SwitchOpts are passed to the Switch function.
 type SwitchOpts struct {
 	// Registers are the user register state.
-	Registers *syscall.PtraceRegs
+	Registers *arch.Registers
 
 	// FloatingPointState is a byte pointer where floating point state is
 	// saved and restored.
@@ -377,7 +377,7 @@ func Emit(w io.Writer) {
 	fmt.Fprintf(w, "#define Syscall 0x%02x\n", Syscall)
 	fmt.Fprintf(w, "#define VirtualizationException 0x%02x\n", VirtualizationException)
 
-	p := &syscall.PtraceRegs{}
+	p := &arch.Registers{}
 	fmt.Fprintf(w, "\n// Ptrace registers.\n")
 	fmt.Fprintf(w, "#define PTRACE_R0       0x%02x\n", reflect.ValueOf(&p.Regs[0]).Pointer()-reflect.ValueOf(p).Pointer())
 	fmt.Fprintf(w, "#define PTRACE_R1       0x%02x\n", reflect.ValueOf(&p.Regs[1]).Pointer()-reflect.ValueOf(p).Pointer())
diff --git a/pkg/sentry/platform/ring0/entry_amd64.go b/pkg/sentry/platform/ring0/entry_amd64.go
index a5ce67885..7fa43c2f5 100644
--- a/pkg/sentry/platform/ring0/entry_amd64.go
+++ b/pkg/sentry/platform/ring0/entry_amd64.go
@@ -17,7 +17,7 @@
 package ring0
 
 import (
-	"syscall"
+	"gvisor.dev/gvisor/pkg/sentry/arch"
 )
 
 // This is an assembly function.
@@ -41,7 +41,7 @@ func swapgs()
 // 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, *syscall.PtraceRegs) Vector
+func sysret(*CPU, *arch.Registers) Vector
 
 // "iret is the cadillac of CPL switching."
 //
@@ -50,7 +50,7 @@ func sysret(*CPU, *syscall.PtraceRegs) Vector
 // 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, *syscall.PtraceRegs) Vector
+func iret(*CPU, *arch.Registers) Vector
 
 // exception is the generic exception entry.
 //
diff --git a/pkg/sentry/syscalls/linux/sys_signal.go b/pkg/sentry/syscalls/linux/sys_signal.go
index 7e1747a0c..582d37e03 100644
--- a/pkg/sentry/syscalls/linux/sys_signal.go
+++ b/pkg/sentry/syscalls/linux/sys_signal.go
@@ -355,7 +355,7 @@ func Pause(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall
 func RtSigpending(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
 	addr := args[0].Pointer()
 	pending := t.PendingSignals()
-	_, err := t.CopyOut(addr, pending)
+	_, err := pending.CopyOut(t, addr)
 	return 0, nil, err
 }
 
@@ -392,7 +392,7 @@ func RtSigtimedwait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne
 
 	if siginfo != 0 {
 		si.FixSignalCodeForUser()
-		if _, err := t.CopyOut(siginfo, si); err != nil {
+		if _, err := si.CopyOut(t, siginfo); err != nil {
 			return 0, nil, err
 		}
 	}
@@ -411,7 +411,7 @@ func RtSigqueueinfo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne
 	// same way), and that the code is in the allowed set. This same logic
 	// appears below in RtSigtgqueueinfo and should be kept in sync.
 	var info arch.SignalInfo
-	if _, err := t.CopyIn(infoAddr, &info); err != nil {
+	if _, err := info.CopyIn(t, infoAddr); err != nil {
 		return 0, nil, err
 	}
 	info.Signo = int32(sig)
@@ -455,7 +455,7 @@ func RtTgsigqueueinfo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *ker
 
 	// Copy in the info. See RtSigqueueinfo above.
 	var info arch.SignalInfo
-	if _, err := t.CopyIn(infoAddr, &info); err != nil {
+	if _, err := info.CopyIn(t, infoAddr); err != nil {
 		return 0, nil, err
 	}
 	info.Signo = int32(sig)
@@ -485,7 +485,7 @@ func RtSigsuspend(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.
 
 	// Copy in the signal mask.
 	var mask linux.SignalSet
-	if _, err := t.CopyIn(sigset, &mask); err != nil {
+	if _, err := mask.CopyIn(t, sigset); err != nil {
 		return 0, nil, err
 	}
 	mask &^= kernel.UnblockableSignals