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| author | Thomas Garnier <thgarnie@google.com> | 2016-08-11 14:49:29 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-09-30 10:12:47 +0200 |
| commit | b4707a7852aac91f89e44c049b459019ebb19f0e (patch) | |
| tree | 667661eb526f732f75c4c15dbe69d781ae6ba0f1 | |
| parent | dab6c838065cac24e68ea0ae00970aa753d7b647 (diff) | |
| download | linux-stable-b4707a7852aac91f89e44c049b459019ebb19f0e.tar.gz linux-stable-b4707a7852aac91f89e44c049b459019ebb19f0e.tar.bz2 linux-stable-b4707a7852aac91f89e44c049b459019ebb19f0e.zip | |
PM / hibernate: Restore processor state before using per-CPU variables
commit 62822e2ec4ad091ba31f823f577ef80db52e3c2c upstream.
Restore the processor state before calling any other functions to
ensure per-CPU variables can be used with KASLR memory randomization.
Tracing functions use per-CPU variables (GS based on x86) and one was
called just before restoring the processor state fully. It resulted
in a double fault when both the tracing & the exception handler
functions tried to use a per-CPU variable.
Fixes: bb3632c6101b (PM / sleep: trace events for suspend/resume)
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Reported-by: Jiri Kosina <jikos@kernel.org>
Tested-by: Rafael J. Wysocki <rafael@kernel.org>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/power/hibernate.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index fca9254280ee..2fc1177383a0 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -299,12 +299,12 @@ static int create_image(int platform_mode) save_processor_state(); trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true); error = swsusp_arch_suspend(); + /* Restore control flow magically appears here */ + restore_processor_state(); trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false); if (error) printk(KERN_ERR "PM: Error %d creating hibernation image\n", error); - /* Restore control flow magically appears here */ - restore_processor_state(); if (!in_suspend) events_check_enabled = false; |