On 09/06/2018 09:07 AM, Sean Christopherson wrote:
...
+
+/* This should cover upto 512 VCPUS (first 64 are covered by hv_clock_boot[]). */
+#define HVC_DECRYPTED_ARRAY_SIZE \
+ ((PAGE_SIZE * 7) / sizeof(struct pvclock_vsyscall_time_info))
I think we can define the size relative to NR_CPUS rather than picking
an arbitrary number of pages, maybe with a BUILD_BUG_ON to make sure
the total size won't require a second 2mb page for __decrpyted.
#define HVC_DECRYPTED_ARRAY_SIZE \
PAGE_ALIGN((NR_CPUS - HVC_BOOT_ARRAY_SIZE) * \
sizeof(struct pvclock_vsyscall_time_info))
Sure works for me.
+static struct pvclock_vsyscall_time_info
+ hv_clock_dec[HVC_DECRYPTED_ARRAY_SIZE] __decrypted_hvclock;
+
static inline struct pvclock_vcpu_time_info *this_cpu_pvti(void)
{
return &this_cpu_read(hv_clock_per_cpu)->pvti;
@@ -267,10 +274,19 @@ static int kvmclock_setup_percpu(unsigned int cpu)
return 0;
/* Use the static page for the first CPUs, allocate otherwise */
- if (cpu < HVC_BOOT_ARRAY_SIZE)
+ if (cpu < HVC_BOOT_ARRAY_SIZE) {
p = &hv_clock_boot[cpu];
- else
- p = kzalloc(sizeof(*p), GFP_KERNEL);
+ } else {
+ /*
+ * When SEV is active, use the static pages from
+ * .data..decrypted_hvclock section. The pages are already
+ * mapped with C=0.
+ */
+ if (sev_active())
+ p = &hv_clock_dec[cpu - HVC_BOOT_ARRAY_SIZE];
+ else
+ p = kzalloc(sizeof(*p), GFP_KERNEL);
+ }
Personal preference, but I think an if-elif-else with a single block
comment would be easier to read.
I can do with that. thanks for your feedback.
/*
* Blah blah blah
*/
if (cpu < HVC_BOOT_ARRAY_SIZE)
p = &hv_clock_boot[cpu];
else if (sev_active())
p = &hv_clock_dec[cpu - HVC_BOOT_ARRAY_SIZE];
else
p = kzalloc(sizeof(*p), GFP_KERNEL);
