Re: [PATCH v8 16/18] KVM: x86: Mark _bss_decrypted section variables as decrypted in page encryption bitmap.

Steve Rutherford
2020-05-30T02:08:51Z

On Tue, May 5, 2020 at 2:20 PM Ashish Kalra <Ashish.Kalra@amd.com> wrote:
>
> From: Ashish Kalra <ashish.kalra@amd.com>
>
> Ensure that _bss_decrypted section variables such as hv_clock_boot and
> wall_clock are marked as decrypted in the page encryption bitmap if
> sev liv migration is supported.
>
> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
> ---
> arch/x86/kernel/kvmclock.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
> index 34b18f6eeb2c..65777bf1218d 100644
> --- a/arch/x86/kernel/kvmclock.c
> +++ b/arch/x86/kernel/kvmclock.c
> @@ -334,6 +334,18 @@ void __init kvmclock_init(void)
> pr_info("kvm-clock: Using msrs %x and %x",
> msr_kvm_system_time, msr_kvm_wall_clock);
>
> + if (sev_live_migration_enabled()) {
> + unsigned long nr_pages;
> + /*
> + * sizeof(hv_clock_boot) is already PAGE_SIZE aligned
> + */
> + early_set_mem_enc_dec_hypercall((unsigned long)hv_clock_boot,
> + 1, 0);
> + nr_pages = DIV_ROUND_UP(sizeof(wall_clock), PAGE_SIZE);
> + early_set_mem_enc_dec_hypercall((unsigned long)&wall_clock,
> + nr_pages, 0);
> + }
> +
> this_cpu_write(hv_clock_per_cpu, &hv_clock_boot[0]);
> kvm_register_clock("primary cpu clock");
> pvclock_set_pvti_cpu0_va(hv_clock_boot);
> --
> 2.17.1
>

Reviewed-by: Steve Rutherford <srutherford@google.com>