1 files changed, 113 insertions, 0 deletions

diff --git a/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.25/0030-ftrace-Disable-function-tracing-during-suspend-resum.patch b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.25/0030-ftrace-Disable-function-tracing-during-suspend-resum.patch
new file mode 100644
index 00000000..3ec5202b
--- /dev/null
+++ b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.25/0030-ftrace-Disable-function-tracing-during-suspend-resum.patch
@@ -0,0 +1,113 @@
+From 951ac5885b5a314d394ea0668dedccd7ed9216e5 Mon Sep 17 00:00:00 2001
+From: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
+Date: Sat, 16 Jun 2012 15:30:45 +0200
+Subject: [PATCH 30/73] ftrace: Disable function tracing during suspend/resume
+ and hibernation, again
+
+commit 443772d408a25af62498793f6f805ce3c559309a upstream.
+
+If function tracing is enabled for some of the low-level suspend/resume
+functions, it leads to triple fault during resume from suspend, ultimately
+ending up in a reboot instead of a resume (or a total refusal to come out
+of suspended state, on some machines).
+
+This issue was explained in more detail in commit f42ac38c59e0a03d (ftrace:
+disable tracing for suspend to ram). However, the changes made by that commit
+got reverted by commit cbe2f5a6e84eebb (tracing: allow tracing of
+suspend/resume & hibernation code again). So, unfortunately since things are
+not yet robust enough to allow tracing of low-level suspend/resume functions,
+suspend/resume is still broken when ftrace is enabled.
+
+So fix this by disabling function tracing during suspend/resume & hibernation.
+
+Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
+Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
+Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
+---
+ kernel/power/hibernate.c |    6 ++++++
+ kernel/power/suspend.c   |    3 +++
+ 2 files changed, 9 insertions(+), 0 deletions(-)
+
+diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
+index 7c0d578..013bd2e 100644
+--- a/kernel/power/hibernate.c
++++ b/kernel/power/hibernate.c
+@@ -367,6 +367,7 @@ int hibernation_snapshot(int platform_mode)
+        }
+ 
+        suspend_console();
++       ftrace_stop();
+        pm_restrict_gfp_mask();
+        error = dpm_suspend(PMSG_FREEZE);
+        if (error)
+@@ -392,6 +393,7 @@ int hibernation_snapshot(int platform_mode)
+        if (error || !in_suspend)
+                pm_restore_gfp_mask();
+ 
++       ftrace_start();
+        resume_console();
+        dpm_complete(msg);
+ 
+@@ -496,6 +498,7 @@ int hibernation_restore(int platform_mode)
+ 
+        pm_prepare_console();
+        suspend_console();
++       ftrace_stop();
+        pm_restrict_gfp_mask();
+        error = dpm_suspend_start(PMSG_QUIESCE);
+        if (!error) {
+@@ -503,6 +506,7 @@ int hibernation_restore(int platform_mode)
+                dpm_resume_end(PMSG_RECOVER);
+        }
+        pm_restore_gfp_mask();
++       ftrace_start();
+        resume_console();
+        pm_restore_console();
+        return error;
+@@ -529,6 +533,7 @@ int hibernation_platform_enter(void)
+ 
+        entering_platform_hibernation = true;
+        suspend_console();
++       ftrace_stop();
+        error = dpm_suspend_start(PMSG_HIBERNATE);
+        if (error) {
+                if (hibernation_ops->recover)
+@@ -572,6 +577,7 @@ int hibernation_platform_enter(void)
+  Resume_devices:
+        entering_platform_hibernation = false;
+        dpm_resume_end(PMSG_RESTORE);
++       ftrace_start();
+        resume_console();
+ 
+  Close:
+diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
+index 4953dc0..af48faa 100644
+--- a/kernel/power/suspend.c
++++ b/kernel/power/suspend.c
+@@ -25,6 +25,7 @@
+ #include <linux/export.h>
+ #include <linux/suspend.h>
+ #include <linux/syscore_ops.h>
++#include <linux/ftrace.h>
+ #include <trace/events/power.h>
+ 
+ #include "power.h"
+@@ -220,6 +221,7 @@ int suspend_devices_and_enter(suspend_state_t state)
+                        goto Close;
+        }
+        suspend_console();
++       ftrace_stop();
+        suspend_test_start();
+        error = dpm_suspend_start(PMSG_SUSPEND);
+        if (error) {
+@@ -239,6 +241,7 @@ int suspend_devices_and_enter(suspend_state_t state)
+        suspend_test_start();
+        dpm_resume_end(PMSG_RESUME);
+        suspend_test_finish("resume devices");
++       ftrace_start();
+        resume_console();
+  Close:
+        if (suspend_ops->end)
+-- 
+1.7.7.6
+