diff options
| author | James Morse <james.morse@arm.com> | 2022-03-15 18:24:10 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-19 13:40:15 +0100 |
| commit | c45d885c5a77df2bc029cca77c1ad1ef25c2efd5 (patch) | |
| tree | e825626fef34293e29189336dbb415924a47aac7 /arch/arm64/kvm | |
| parent | 1bb1944970a9dc2d05160e014a2aac634b0eca48 (diff) | |
arm64: Add percpu vectors for EL1
commit bd09128d16fac3c34b80bd6a29088ac632e8ce09 upstream.
The Spectre-BHB workaround adds a firmware call to the vectors. This
is needed on some CPUs, but not others. To avoid the unaffected CPU in
a big/little pair from making the firmware call, create per cpu vectors.
The per-cpu vectors only apply when returning from EL0.
Systems using KPTI can use the canonical 'full-fat' vectors directly at
EL1, the trampoline exit code will switch to this_cpu_vector on exit to
EL0. Systems not using KPTI should always use this_cpu_vector.
this_cpu_vector will point at a vector in tramp_vecs or
__bp_harden_el1_vectors, depending on whether KPTI is in use.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/arm64/kvm')
| -rw-r--r-- | arch/arm64/kvm/hyp/switch.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 14607fac7ca3..768983bd2326 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -25,6 +25,7 @@ #include <asm/debug-monitors.h> #include <asm/processor.h> #include <asm/thread_info.h> +#include <asm/vectors.h> extern struct exception_table_entry __start___kvm_ex_table; extern struct exception_table_entry __stop___kvm_ex_table; @@ -152,7 +153,7 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) static void deactivate_traps_vhe(void) { - extern char vectors[]; /* kernel exception vectors */ + const char *host_vectors = vectors; write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); /* @@ -163,7 +164,10 @@ static void deactivate_traps_vhe(void) asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_1165522)); write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1); - write_sysreg(vectors, vbar_el1); + + if (!arm64_kernel_unmapped_at_el0()) + host_vectors = __this_cpu_read(this_cpu_vector); + write_sysreg(host_vectors, vbar_el1); } NOKPROBE_SYMBOL(deactivate_traps_vhe); |