diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index b3df8e5986e0..012dab9d9a01 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -285,6 +285,20 @@ void __init arm64_update_smccc_conduit(struct alt_instr *alt, *updptr = cpu_to_le32(insn); } +void __init arm64_enable_wa2_handling(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, + int nr_inst) +{ + BUG_ON(nr_inst != 1); + /* + * Only allow mitigation on EL1 entry/exit and guest + * ARCH_WORKAROUND_2 handling if the SSBD state allows it to + * be flipped. + */ + if (arm64_get_ssbd_state() == ARM64_SSBD_KERNEL) + *updptr = cpu_to_le32(aarch64_insn_gen_nop()); +} + static void arm64_set_ssbd_mitigation(bool state) { switch (psci_ops.conduit) { diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index caa77d060af1..5a585976d14c 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -142,6 +142,9 @@ alternative_else_nop_endif // to save/restore them if required. .macro apply_ssbd, state, targ, tmp1, tmp2 #ifdef CONFIG_ARM64_SSBD +alternative_cb arm64_enable_wa2_handling + b \targ +alternative_cb_end ldr_this_cpu \tmp2, arm64_ssbd_callback_required, \tmp1 cbz \tmp2, \targ mov w0, #ARM_SMCCC_ARCH_WORKAROUND_2