From 32592edb940df95dce3b8fcc62fbaf4c1e5522bf Mon Sep 17 00:00:00 2001 From: Todd E Brandt Date: Wed, 2 Mar 2016 16:05:29 -0800 Subject: [PATCH 1/1] PM / sleep / x86: Fix crash on graph trace through x86 suspend commit 92f9e179a702a6adbc11e2fedc76ecd6ffc9e3f7 upstream. Pause/unpause graph tracing around do_suspend_lowlevel as it has inconsistent call/return info after it jumps to the wakeup vector. The graph trace buffer will otherwise become misaligned and may eventually crash and hang on suspend. To reproduce the issue and test the fix: Run a function_graph trace over suspend/resume and set the graph function to suspend_devices_and_enter. This consistently hangs the system without this fix. Signed-off-by: Todd Brandt Signed-off-by: Rafael J. Wysocki [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- arch/x86/kernel/acpi/sleep.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index 103b6ab368d3..0d56eaa629ff 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -15,6 +15,7 @@ #include #include +#include #include "realmode/wakeup.h" #include "sleep.h" @@ -102,7 +103,13 @@ int acpi_suspend_lowlevel(void) saved_magic = 0x123456789abcdef0L; #endif /* CONFIG_64BIT */ + /* + * Pause/unpause graph tracing around do_suspend_lowlevel as it has + * inconsistent call/return info after it jumps to the wakeup vector. + */ + pause_graph_tracing(); do_suspend_lowlevel(); + unpause_graph_tracing(); return 0; } -- 2.39.2