runtime: windows/arm fix tracebacks printed from sigpanic
The exception handler modifies the stack and continuation context so
it looks like the faulting code calls sigpanic() directly. The call was
not set up correctly on ARM, because it did not handle the link register
correctly. This change handles the link register correctly for ARM.
Updates #28854
Change-Id: I7ccf838adfc05cd968a5edd7d19ebba6a2478360
Reviewed-on: https://go-review.googlesource.com/c/150957
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/runtime/defs_windows_386.go b/src/runtime/defs_windows_386.go
index 38b30b7..8c0d6d8 100644
--- a/src/runtime/defs_windows_386.go
+++ b/src/runtime/defs_windows_386.go
@@ -105,10 +105,11 @@
func (c *context) sp() uintptr { return uintptr(c.esp) }
// 386 does not have link register, so this returns 0.
-func (c *context) lr() uintptr { return 0 }
+func (c *context) lr() uintptr { return 0 }
+func (c *context) set_lr(x uintptr) {}
-func (c *context) setip(x uintptr) { c.eip = uint32(x) }
-func (c *context) setsp(x uintptr) { c.esp = uint32(x) }
+func (c *context) set_ip(x uintptr) { c.eip = uint32(x) }
+func (c *context) set_sp(x uintptr) { c.esp = uint32(x) }
func dumpregs(r *context) {
print("eax ", hex(r.eax), "\n")
diff --git a/src/runtime/defs_windows_amd64.go b/src/runtime/defs_windows_amd64.go
index 37508c09..42a446d 100644
--- a/src/runtime/defs_windows_amd64.go
+++ b/src/runtime/defs_windows_amd64.go
@@ -120,10 +120,11 @@
func (c *context) sp() uintptr { return uintptr(c.rsp) }
// Amd64 does not have link register, so this returns 0.
-func (c *context) lr() uintptr { return 0 }
+func (c *context) lr() uintptr { return 0 }
+func (c *context) set_lr(x uintptr) {}
-func (c *context) setip(x uintptr) { c.rip = uint64(x) }
-func (c *context) setsp(x uintptr) { c.rsp = uint64(x) }
+func (c *context) set_ip(x uintptr) { c.rip = uint64(x) }
+func (c *context) set_sp(x uintptr) { c.rsp = uint64(x) }
func dumpregs(r *context) {
print("rax ", hex(r.rax), "\n")
diff --git a/src/runtime/defs_windows_arm.go b/src/runtime/defs_windows_arm.go
index 1140f61..049f5b6 100644
--- a/src/runtime/defs_windows_arm.go
+++ b/src/runtime/defs_windows_arm.go
@@ -104,8 +104,9 @@
func (c *context) sp() uintptr { return uintptr(c.spr) }
func (c *context) lr() uintptr { return uintptr(c.lrr) }
-func (c *context) setip(x uintptr) { c.pc = uint32(x) }
-func (c *context) setsp(x uintptr) { c.spr = uint32(x) }
+func (c *context) set_ip(x uintptr) { c.pc = uint32(x) }
+func (c *context) set_sp(x uintptr) { c.spr = uint32(x) }
+func (c *context) set_lr(x uintptr) { c.lrr = uint32(x) }
func dumpregs(r *context) {
print("r0 ", hex(r.r0), "\n")
diff --git a/src/runtime/signal_windows.go b/src/runtime/signal_windows.go
index e8a64da..e6a75a16 100644
--- a/src/runtime/signal_windows.go
+++ b/src/runtime/signal_windows.go
@@ -117,10 +117,18 @@
if r.ip() != 0 {
sp := unsafe.Pointer(r.sp())
sp = add(sp, ^(unsafe.Sizeof(uintptr(0)) - 1)) // sp--
- *((*uintptr)(sp)) = r.ip()
- r.setsp(uintptr(sp))
+ r.set_sp(uintptr(sp))
+ switch GOARCH {
+ default:
+ panic("unsupported architecture")
+ case "386", "amd64":
+ *((*uintptr)(sp)) = r.ip()
+ case "arm":
+ *((*uintptr)(sp)) = r.lr()
+ r.set_lr(r.ip())
+ }
}
- r.setip(funcPC(sigpanic))
+ r.set_ip(funcPC(sigpanic))
return _EXCEPTION_CONTINUE_EXECUTION
}
