From: Tianyu Lan <tiala@xxxxxxxxxxxxx>
Read processor amd memory info from specific address which are
populated by Hyper-V. Initialize smp cpu related ops, pvalidate
system memory and add it into e820 table.
Signed-off-by: Tianyu Lan <tiala@xxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/mshyperv.c | 85 ++++++++++++++++++++++++++++++++++
1 file changed, 85 insertions(+)
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index ace5901ba0fc..b1871a7bb4c9 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -32,6 +32,12 @@
#include <asm/nmi.h>
#include <clocksource/hyperv_timer.h>
#include <asm/numa.h>
+#include <asm/coco.h>
+#include <asm/io_apic.h>
+#include <asm/svm.h>
+#include <asm/sev.h>
+#include <asm/realmode.h>
+#include <asm/e820/api.h>
/* Is Linux running as the root partition? */
bool hv_root_partition;
@@ -251,6 +257,30 @@ static void __init hv_smp_prepare_cpus(unsigned int max_cpus)
}
#endif
+static u32 processor_count;
+
+static __init void hv_snp_get_smp_config(unsigned int early)
+{
+ if (!early) {
+ while (num_processors < processor_count) {
+ early_per_cpu(x86_cpu_to_apicid, num_processors) = num_processors;
+ early_per_cpu(x86_bios_cpu_apicid, num_processors) = num_processors;
+ physid_set(num_processors, phys_cpu_present_map);
+ set_cpu_possible(num_processors, true);
+ set_cpu_present(num_processors, true);
+ num_processors++;
+ }
+ }
+}
+
+struct memory_map_entry {
+ u64 starting_gpn;
+ u64 numpages;
+ u16 type;
+ u16 flags;
+ u32 reserved;
+};
+
static void __init ms_hyperv_init_platform(void)
{
int hv_max_functions_eax;
@@ -258,6 +288,11 @@ static void __init ms_hyperv_init_platform(void)
int hv_host_info_ebx;
int hv_host_info_ecx;
int hv_host_info_edx;
+ struct memory_map_entry *entry;
+ struct e820_entry *e820_entry;
+ u64 e820_end;
+ u64 ram_end;
+ u64 page;
#ifdef CONFIG_PARAVIRT
pv_info.name = "Hyper-V";
@@ -466,6 +501,56 @@ static void __init ms_hyperv_init_platform(void)
if (!(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT))
mark_tsc_unstable("running on Hyper-V");
+ if (isolation_type_en_snp()) {
+ /*
+ * Hyper-V enlightened snp guest boots kernel
+ * directly without bootloader and so roms,
+ * bios regions and reserve resources are not
+ * available. Set these callback to NULL.
+ */
+ x86_platform.legacy.reserve_bios_regions = x86_init_noop;
+ x86_init.resources.probe_roms = x86_init_noop;
+ x86_init.resources.reserve_resources = x86_init_noop;
+ x86_init.mpparse.find_smp_config = x86_init_noop;
+ x86_init.mpparse.get_smp_config = hv_snp_get_smp_config;
+
+ /*
+ * Hyper-V SEV-SNP enlightened guest doesn't support ioapic
+ * and legacy APIC page read/write. Switch to hv apic here.
+ */
+ disable_ioapic_support();
+
+ /* Read processor number and memory layout. */
+ processor_count = *(u32 *)__va(EN_SEV_SNP_PROCESSOR_INFO_ADDR);
+ entry = (struct memory_map_entry *)(__va(EN_SEV_SNP_PROCESSOR_INFO_ADDR)
+ + sizeof(struct memory_map_entry));
+
+ /*
+ * E820 table in the memory just describes memory for
+ * kernel, ACPI table, cmdline, boot params and ramdisk.
+ * Hyper-V popoulates the rest memory layout in the EN_SEV_
+ * SNP_PROCESSOR_INFO_ADDR.
+ */
+ for (; entry->numpages != 0; entry++) {
+ e820_entry = &e820_table->entries[
+ e820_table->nr_entries - 1];
+ e820_end = e820_entry->addr + e820_entry->size;
+ ram_end = (entry->starting_gpn +
+ entry->numpages) * PAGE_SIZE;
+
+ if (e820_end < entry->starting_gpn * PAGE_SIZE)
+ e820_end = entry->starting_gpn * PAGE_SIZE;
+
+ if (e820_end < ram_end) {
+ pr_info("Hyper-V: add e820 entry [mem %#018Lx-%#018Lx]\n", e820_end, ram_end - 1);
+ e820__range_add(e820_end, ram_end - e820_end,
+ E820_TYPE_RAM);
+ for (page = e820_end; page < ram_end; page += PAGE_SIZE)
+ pvalidate((unsigned long)__va(page), RMP_PG_SIZE_4K, true);
+ }
+ }
+ }
+
hardlockup_detector_disable();
}
--
2.25.1
