diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/hyp-entry.S')
| -rw-r--r-- | arch/arm64/kvm/hyp/hyp-entry.S | 38 |
1 files changed, 37 insertions, 1 deletions
diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S index 3418c1dda236..bf4988f9dae8 100644 --- a/arch/arm64/kvm/hyp/hyp-entry.S +++ b/arch/arm64/kvm/hyp/hyp-entry.S @@ -107,8 +107,44 @@ el1_hvc_guest: */ ldr x1, [sp] // Guest's x0 eor w1, w1, #ARM_SMCCC_ARCH_WORKAROUND_1 + cbz w1, wa_epilogue + + /* ARM_SMCCC_ARCH_WORKAROUND_2 handling */ + eor w1, w1, #(ARM_SMCCC_ARCH_WORKAROUND_1 ^ \ + ARM_SMCCC_ARCH_WORKAROUND_2) cbnz w1, el1_trap - mov x0, x1 + +#ifdef CONFIG_ARM64_SSBD +alternative_cb arm64_enable_wa2_handling + b wa2_end +alternative_cb_end + get_vcpu_ptr x2, x0 + ldr x0, [x2, #VCPU_WORKAROUND_FLAGS] + + // Sanitize the argument and update the guest flags + ldr x1, [sp, #8] // Guest's x1 + clz w1, w1 // Murphy's device: + lsr w1, w1, #5 // w1 = !!w1 without using + eor w1, w1, #1 // the flags... + bfi x0, x1, #VCPU_WORKAROUND_2_FLAG_SHIFT, #1 + str x0, [x2, #VCPU_WORKAROUND_FLAGS] + + /* Check that we actually need to perform the call */ + hyp_ldr_this_cpu x0, arm64_ssbd_callback_required, x2 + cbz x0, wa2_end + + mov w0, #ARM_SMCCC_ARCH_WORKAROUND_2 + smc #0 + + /* Don't leak data from the SMC call */ + mov x3, xzr +wa2_end: + mov x2, xzr + mov x1, xzr +#endif + +wa_epilogue: + mov x0, xzr add sp, sp, #16 eret |