This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[PATCH] PR81393: S/390: libgo: Fix ptrace register set accessors.


ptrace SETREGS and GETREGS were never supported on S/390.  The macros
were accidentally defined in the Glibc header though.  A recent Glibc
change removed them breaking libgo build on S/390.

This patch changes the ptrace calls to use PEEKUSR_AREA/POKEUSR_AREA to
access the register sets.  That's what GDB does.

Bootstrapped and regression tested on s390x.

Bye,

-Andreas-
---
 libgo/go/syscall/syscall_linux_s390.go  | 16 +++++++++++++---
 libgo/go/syscall/syscall_linux_s390x.go | 30 +++++++++++++++++++++++++++---
 2 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/libgo/go/syscall/syscall_linux_s390.go b/libgo/go/syscall/syscall_linux_s390.go
index d6d3f6a..9364bcd 100644
--- a/libgo/go/syscall/syscall_linux_s390.go
+++ b/libgo/go/syscall/syscall_linux_s390.go
@@ -4,6 +4,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// See the s390x version for why we don't use GETREGSET/SETREGSET
+
 package syscall
 
 import "unsafe"
@@ -12,10 +14,18 @@ func (r *PtraceRegs) PC() uint64 { return uint64(r.Psw.addr) }
 
 func (r *PtraceRegs) SetPC(pc uint64) { r.Psw.addr = uint32(pc) }
 
-func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
-	return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout)))
+func PtraceGetRegs(pid int, regs *PtraceRegs) (err error) {
+	parea :=  _ptrace_area{ _sizeof_ptrace_area,
+				0,
+				uint32(uintptr(unsafe.Pointer(regs))) }
+	return ptrace(PTRACE_PEEKUSR_AREA, pid,
+		      uintptr(unsafe.Pointer(&parea)), 0)
 }
 
 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
-	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
+	parea := _ptrace_area{ _sizeof_ptrace_area,
+			       0,
+			       uint32(uintptr(unsafe.Pointer(regs))) }
+	return ptrace(PTRACE_POKEUSR_AREA, pid,
+		      uintptr(unsafe.Pointer(&parea)), 0)
 }
diff --git a/libgo/go/syscall/syscall_linux_s390x.go b/libgo/go/syscall/syscall_linux_s390x.go
index f3701dc..8d9ca84 100644
--- a/libgo/go/syscall/syscall_linux_s390x.go
+++ b/libgo/go/syscall/syscall_linux_s390x.go
@@ -4,6 +4,24 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+
+// The PtraceRegs struct generated for go looks like this:
+//
+// type PtraceRegs struct
+// {
+//   Psw _psw_t;
+//   Gprs [15+1]uint64;
+//   Acrs [15+1]uint32;
+//   Orig_gpr2 uint64;
+//   Fp_regs _s390_fp_regs;
+//   Per_info _per_struct;
+//   Ieee_instruction_pointer uint64;
+// }
+//
+// The GETREGSET/SETREGSET ptrace commands on S/390 only read/write
+// the content up to Orig_gpr2.  Hence, we use
+// PEEKUSR_AREA/POKEUSR_AREA like GDB does.
+
 package syscall
 
 import "unsafe"
@@ -12,10 +30,16 @@ func (r *PtraceRegs) PC() uint64 { return r.Psw.addr }
 
 func (r *PtraceRegs) SetPC(pc uint64) { r.Psw.addr = pc }
 
-func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
-	return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout)))
+func PtraceGetRegs(pid int, regs *PtraceRegs) (err error) {
+	parea := _ptrace_area{ _sizeof_ptrace_area,
+			       0,
+			       uint64(uintptr(unsafe.Pointer(regs))) }
+	return ptrace(PTRACE_PEEKUSR_AREA, pid, uintptr(unsafe.Pointer(&parea)), 0)
 }
 
 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
-	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
+	parea := _ptrace_area{ _sizeof_ptrace_area,
+			       0,
+			       uint64(uintptr(unsafe.Pointer(regs))) }
+	return ptrace(PTRACE_POKEUSR_AREA, pid, uintptr(unsafe.Pointer(&parea)), 0)
 }
-- 
2.9.1


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]