powerpc/pseries: Call ibm,os-term if the ibm,extended-os-term is present

We have had issues in the past with ibm,os-term initiating shutdown of a
partition. This is confusing to the user, especially if panic_timeout is
non zero.

The temporary fix was to avoid calling ibm,os-term if a panic_timeout was set
and since we set it on every boot we basically never call ibm,os-term.

An extended version of ibm,os-term has since been implemented which gives us
the behaviour we want:

  "When the platform supports extended ibm,os-term behavior, the return to the
  RTAS will always occur unless there is a kernel assisted dump active as
  initiated by an ibm,configure-kernel-dump call."

This patch checks for the ibm,extended-os-term property and calls ibm,os-term
if it exists.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 9 insertions, 6 deletions

diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 74367841615a..0e1ec6f746f6 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -691,10 +691,14 @@ void rtas_os_term(char *str)
 {
         int status;
 
-        if (panic_timeout)
-                return;
-
-        if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term"))
+        /*
+         * Firmware with the ibm,extended-os-term property is guaranteed
+         * to always return from an ibm,os-term call. Earlier versions without
+         * this property may terminate the partition which we want to avoid
+         * since it interferes with panic_timeout.
+         */
+        if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term") ||
+            RTAS_UNKNOWN_SERVICE == rtas_token("ibm,extended-os-term"))
                 return;
 
         snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
@@ -705,8 +709,7 @@ void rtas_os_term(char *str)
         } while (rtas_busy_delay(status));
 
         if (status != 0)
-                printk(KERN_EMERG "ibm,os-term call failed %d\n",
-                               status);
+                printk(KERN_EMERG "ibm,os-term call failed %d\n", status);
 }
 
 static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;