PC should be one past the faulting insn. Add better commentary
for the machine-check exception path.
Reported-by: Al Viro <v...@zeniv.linux.org.uk>
Signed-off-by: Richard Henderson <r...@twiddle.net>
---
target-alpha/helper.c | 2 ++
target-alpha/mem_helper.c | 9 ++++++++-
2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/target-alpha/helper.c b/target-alpha/helper.c
index 7c053a3..8d1df2d 100644
--- a/target-alpha/helper.c
+++ b/target-alpha/helper.c
@@ -527,6 +527,8 @@ void QEMU_NORETURN dynamic_excp(CPUAlphaState *env,
uintptr_t retaddr,
env->error_code = error;
if (retaddr) {
cpu_restore_state(cs, retaddr);
+ /* Floating-point exceptions (our only users) point to the next PC. */
+ env->pc += 4;
}
cpu_loop_exit(cs);
}
diff --git a/target-alpha/mem_helper.c b/target-alpha/mem_helper.c
index fc4f57a..7b5e30d 100644
--- a/target-alpha/mem_helper.c
+++ b/target-alpha/mem_helper.c
@@ -128,7 +128,14 @@ void alpha_cpu_unassigned_access(CPUState *cs, hwaddr addr,
env->trap_arg0 = addr;
env->trap_arg1 = is_write ? 1 : 0;
- dynamic_excp(env, 0, EXCP_MCHK, 0);
+ cs->exception_index = EXCP_MCHK;
+ env->error_code = 0;
+
+ /* ??? We should cpu_restore_state to the faulting insn, but this hook
+ does not have access to the retaddr value from the orignal helper.
+ It's all moot until the QEMU PALcode grows an MCHK handler. */
+
+ cpu_loop_exit(cs);
}
/* try to fill the TLB and return an exception if error. If retaddr is
--
1.9.3
