diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-07-20 10:47:16 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-07-22 15:16:08 +0200 |
| commit | ec40f159ec11f4fd18bf89291e597a8a3355854f (patch) | |
| tree | 30273e2c1fd64b4a6616bc5fa948ce00a7f80417 /arch/arm64/kernel/hibernate.c | |
| parent | 5c0c86a03b4c3a5720d8c2145a67d13be8a30700 (diff) | |
arm64: ssbd: Restore mitigation status on CPU resume
commit 647d0519b53f440a55df163de21c52a8205431cc upstream.
On a system where firmware can dynamically change the state of the
mitigation, the CPU will always come up with the mitigation enabled,
including when coming back from suspend.
If the user has requested "no mitigation" via a command line option,
let's enforce it by calling into the firmware again to disable it.
Similarily, for a resume from hibernate, the mitigation could have
been disabled by the boot kernel. Let's ensure that it is set
back on in that case.
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm64/kernel/hibernate.c')
| -rw-r--r-- | arch/arm64/kernel/hibernate.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c index 1ec5f28c39fc..6b2686d54411 100644 --- a/arch/arm64/kernel/hibernate.c +++ b/arch/arm64/kernel/hibernate.c @@ -313,6 +313,17 @@ int swsusp_arch_suspend(void) sleep_cpu = -EINVAL; __cpu_suspend_exit(); + + /* + * Just in case the boot kernel did turn the SSBD + * mitigation off behind our back, let's set the state + * to what we expect it to be. + */ + switch (arm64_get_ssbd_state()) { + case ARM64_SSBD_FORCE_ENABLE: + case ARM64_SSBD_KERNEL: + arm64_set_ssbd_mitigation(true); + } } local_daif_restore(flags); |