diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2017-09-26 15:57:16 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-05 09:41:46 +0200 |
| commit | 638e7874f68208d18d392cdd61ba389e53f6bb0c (patch) | |
| tree | 0a2b94fb7b536ed4914517975c57071ea72bd640 | |
| parent | 9237605e0bfb0e469b54344a4455e6b241d6c0c9 (diff) | |
arm64: Make sure SPsel is always set
commit 5371513fb338fb9989c569dc071326d369d6ade8 upstream.
When the kernel is entered at EL2 on an ARMv8.0 system, we construct
the EL1 pstate and make sure this uses the the EL1 stack pointer
(we perform an exception return to EL1h).
But if the kernel is either entered at EL1 or stays at EL2 (because
we're on a VHE-capable system), we fail to set SPsel, and use whatever
stack selection the higher exception level has choosen for us.
Let's not take any chance, and make sure that SPsel is set to one
before we decide the mode we're going to run in.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/arm64/kernel/head.S | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 20ceb5edf7b8..d019c3a58cc2 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -446,6 +446,7 @@ ENDPROC(__mmap_switched) * booted in EL1 or EL2 respectively. */ ENTRY(el2_setup) + msr SPsel, #1 // We want to use SP_EL{1,2} mrs x0, CurrentEL cmp x0, #CurrentEL_EL2 b.ne 1f |