[PATCH v9 16/18] KVM: x86: Mark _bss_decrypted section variables as decrypted in page encryption bitmap.

From: Ashish Kalra
Date: Tue Dec 08 2020 - 17:10:01 EST


From: Ashish Kalra <ashish.kalra@xxxxxxx>

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 live migration is supported.

Signed-off-by: Ashish Kalra <ashish.kalra@xxxxxxx>
---
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 aa593743acf6..f80cc637ff2c 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -333,6 +333,18 @@ 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