diff options
| author | Will Deacon <will@kernel.org> | 2020-11-13 14:38:44 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2020-11-16 13:43:05 +0300 |
| commit | b881cdce77b48bd488f268041f32951bab89bb0f (patch) | |
| tree | ee08e27ab59bdf43f567d3edaa8e0ea5151d14a3 /arch/arm64/include/asm/kvm_asm.h | |
| parent | da592e68a5a333b81111bd6336838764732f723e (diff) | |
| download | linux-b881cdce77b48bd488f268041f32951bab89bb0f.tar.xz | |
KVM: arm64: Allocate hyp vectors statically
The EL2 vectors installed when a guest is running point at one of the
following configurations for a given CPU:
- Straight at __kvm_hyp_vector
- A trampoline containing an SMC sequence to mitigate Spectre-v2 and
then a direct branch to __kvm_hyp_vector
- A dynamically-allocated trampoline which has an indirect branch to
__kvm_hyp_vector
- A dynamically-allocated trampoline containing an SMC sequence to
mitigate Spectre-v2 and then an indirect branch to __kvm_hyp_vector
The indirect branches mean that VA randomization at EL2 isn't trivially
bypassable using Spectre-v3a (where the vector base is readable by the
guest).
Rather than populate these vectors dynamically, configure everything
statically and use an enumerated type to identify the vector "slot"
corresponding to one of the configurations above. This both simplifies
the code, but also makes it much easier to implement at EL2 later on.
Signed-off-by: Will Deacon <will@kernel.org>
[maz: fixed double call to kvm_init_vector_slots() on nVHE]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20201113113847.21619-8-will@kernel.org
Diffstat (limited to 'arch/arm64/include/asm/kvm_asm.h')
| -rw-r--r-- | arch/arm64/include/asm/kvm_asm.h | 5 |
1 files changed, 0 insertions, 5 deletions
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 54387ccd1ab2..94b7c9a99576 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -34,8 +34,6 @@ */ #define KVM_VECTOR_PREAMBLE (2 * AARCH64_INSN_SIZE) -#define __SMCCC_WORKAROUND_1_SMC_SZ 36 - #define KVM_HOST_SMCCC_ID(id) \ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ ARM_SMCCC_SMC_64, \ @@ -175,7 +173,6 @@ extern unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; DECLARE_KVM_NVHE_SYM(__per_cpu_start); DECLARE_KVM_NVHE_SYM(__per_cpu_end); -extern atomic_t arm64_el2_vector_last_slot; DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) @@ -198,8 +195,6 @@ extern void __vgic_v3_init_lrs(void); extern u32 __kvm_get_mdcr_el2(void); -extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ]; - /* * Obtain the PC-relative address of a kernel symbol * s: symbol |