[Qemu-devel] [PATCH v4] ppc: spapr-rtas - implement os-term rtas call

[Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>]

PAPR compliant guest calls this in absence of kdump. This finally
reaches the guest and can be handled according to the policies set by
higher level tools(like taking dump) for further analysis by tools like
crash.

Linux kernel calls this only when the extended version of os,term is
implemented to make sure that a return to the linux kernel is gauranteed.

CC: Benjamin Herrenschmidt <benh@au1.ibm.com>
CC: Anton Blanchard <anton@samba.org>
CC: Alexander Graf <agraf@suse.de>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>

---

v2: rebase to ppcnext
v3: Do not stop the VM, and update comments
v4: update spapr_register_rtas and qapi_event changes
---
 hw/ppc/spapr_rtas.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index 9ba1ba6..b11de41 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -277,6 +277,38 @@ static void rtas_ibm_set_system_parameter(PowerPCCPU *cpu,
     rtas_st(rets, 0, ret);
 }
 
+static void rtas_ibm_os_term(PowerPCCPU *cpu,
+                            sPAPREnvironment *spapr,
+                            uint32_t token, uint32_t nargs,
+                            target_ulong args,
+                            uint32_t nret, target_ulong rets)
+{
+    target_ulong ret = 0;
+
+    qapi_event_send_guest_panicked(GUEST_PANIC_ACTION_PAUSE, &error_abort);
+
+    rtas_st(rets, 0, ret);
+}
+
+/*
+ * According to PAPR, rtas ibm,os-term, does not gaurantee a return
+ * back to the guest cpu.
+ *
+ * While an additional ibm,extended-os-term property indicates that
+ * rtas call return will always occur. Below function implements a
+ * place holder for the same.
+ */
+static void rtas_ibm_ext_os_term(PowerPCCPU *cpu,
+                            sPAPREnvironment *spapr,
+                            uint32_t token, uint32_t nargs,
+                            target_ulong args,
+                            uint32_t nret, target_ulong rets)
+{
+    target_ulong ret = RTAS_OUT_NOT_SUPPORTED;
+
+    rtas_st(rets, 0, ret);
+}
+
 static struct rtas_call {
     const char *name;
     spapr_rtas_fn fn;
@@ -404,6 +436,10 @@ static void core_rtas_register_types(void)
     spapr_rtas_register(RTAS_IBM_SET_SYSTEM_PARAMETER,
                         "ibm,set-system-parameter",
                         rtas_ibm_set_system_parameter);
+    spapr_rtas_register(RTAS_IBM_OS_TERM, "ibm,os-term",
+                        rtas_ibm_os_term);
+    spapr_rtas_register(RTAS_IBM_EXTENDED_OS_TERM, "ibm,extended-os-term",
+                        rtas_ibm_ext_os_term);
 }
 
 type_init(core_rtas_register_types)
-- 
1.8.3.1