diff --git a/sys/arch/i386/i386/genassym.cf b/sys/arch/i386/i386/genassym.cf
index 3e5eac33336..fc9211990b1 100644
--- a/sys/arch/i386/i386/genassym.cf
+++ b/sys/arch/i386/i386/genassym.cf
@@ -377,6 +377,7 @@ define L2_FRAME L2_FRAME
define VM_GUEST_XENPV VM_GUEST_XENPV
define VM_GUEST_XENPVH VM_GUEST_XENPVH
+define VM_GUEST_GENPVH VM_GUEST_GENPVH
ifdef XEN
define CPU_INFO_VCPU offsetof(struct cpu_info, ci_vcpu)
@@ -391,7 +392,12 @@ define START_INFO_STORE_MFN offsetof(struct start_info, store_mfn)
define SIF_INITDOMAIN SIF_INITDOMAIN
define EVTCHN_UPCALL_PENDING offsetof(struct vcpu_info, evtchn_upcall_pending)
define EVTCHN_UPCALL_MASK offsetof(struct vcpu_info, evtchn_upcall_mask)
-
+define HVM_START_INFO_SIZE sizeof(struct hvm_start_info)
+define START_INFO_VERSION offsetof(struct hvm_start_info, version)
+define MMAP_PADDR offsetof(struct hvm_start_info, memmap_paddr)
+define MMAP_ENTRIES offsetof(struct hvm_start_info, memmap_entries)
+define MMAP_ENTRY_SIZE sizeof(struct hvm_memmap_table_entry)
+define CMDLINE_PADDR offsetof(struct hvm_start_info, cmdline_paddr)
define HYPERVISOR_sched_op __HYPERVISOR_sched_op
define SCHEDOP_yield SCHEDOP_yield
endif /* XEN */
diff --git a/sys/arch/i386/i386/locore.S b/sys/arch/i386/i386/locore.S
index 06a4ba41a81..9ba754f8d6d 100644
--- a/sys/arch/i386/i386/locore.S
+++ b/sys/arch/i386/i386/locore.S
@@ -244,11 +244,12 @@ __KERNEL_RCSID(0, "$NetBSD: locore.S,v 1.198 2024/07/31 20:05:28 andvar Exp $");
#ifdef XEN
#define __ASSEMBLY__
+#include <xen/include/public/arch-x86/cpuid.h>
#include <xen/include/public/elfnote.h>
#include <xen/include/public/xen.h>
#define ELFNOTE(name, type, desctype, descdata...) \
-.pushsection .note.name ; \
+.pushsection .note.name, "a", @note ; \
.align 4 ; \
.long 2f - 1f /* namesz */ ; \
.long 4f - 3f /* descsz */ ; \
@@ -272,7 +273,7 @@ __KERNEL_RCSID(0, "$NetBSD: locore.S,v 1.198 2024/07/31 20:05:28 andvar Exp $");
ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, .long, start)
#else
ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET, .long, 0)
- ELFNOTE(Xen, XEN_ELFNOTE_PHYS32_ENTRY, .long, RELOC(start_xenpvh))
+ ELFNOTE(Xen, XEN_ELFNOTE_PHYS32_ENTRY, .long, RELOC(start_pvh))
#endif /* XENPV */
ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, .long, hypercall_page)
ELFNOTE(Xen, XEN_ELFNOTE_HV_START_LOW, .long, HYPERVISOR_VIRT_START)
@@ -1193,7 +1194,7 @@ END(start)
#if defined(XEN)
#ifndef XENPV
/* entry point for Xen PVH */
-ENTRY(start_xenpvh)
+ENTRY(start_pvh)
/* Xen doesn't start us with a valid gdt */
movl $RELOC(gdtdesc_xenpvh), %eax
lgdt (%eax)
@@ -1216,6 +1217,93 @@ ENTRY(start_xenpvh)
rep
stosb
+ /*
+ * Here, we have 2 cases :
+ *
+ * 1) We have been started by Xen
+ * 2) We have been started by another VMM (Qemu, Firecracker, ...)
+ *
+ * The main difference is that, when we are started by Xen,
+ * %ebx (addr of the hvm_start_info structure) is pointing to a
+ * location that will be mapped correctly later.
+ *
+ * In the second case, we have to copy this structure (and all
+ * the information contained in it) to a location that will be
+ * mapped later : __kernel_end
+ *
+ * To distinguish between the 2 cases, we'll use the 'cpuid' instruction
+ */
+
+ push %ebx
+ xorl %eax, %eax
+ cpuid
+ cmpl $0x1, %eax /* Check if we can call CPUID with eax=1 */
+ jb .start_genpvh
+ xorl %eax, %eax
+ inc %eax
+ cpuid
+ shr $31, %ecx
+ testb $1, %cl /* Check if bit 31 of ECX (hypervisor) is set */
+ jz .start_genpvh
+ xorl %eax, %eax
+ inc %eax
+ shl $30, %eax
+ cpuid /* Calling cpuid with eax=0x40000000 */
+ cmp $XEN_CPUID_SIGNATURE_EBX, %ebx /* "VneX" */
+ je .start_xen
+
+ /* We have been started by a VMM that is *not* Xen */
+
+.start_genpvh:
+
+ /* First, copy the hvm_start_info structure to __kernel_end */
+ pop %ebx
+ movl %ebx, %esi
+ movl $RELOC(__kernel_end), %edi
+ movl $HVM_START_INFO_SIZE, %ecx
+ shrl $2, %ecx
+ rep movsl
+
+ /* Copy cmdline_paddr after hvm_start_info */
+ movl CMDLINE_PADDR(%ebx), %esi
+ movl $RELOC(__kernel_end), %ecx
+ movl %edi, CMDLINE_PADDR(%ecx) /* Set new cmdline_paddr in hvm_start_info */
+ .cmdline_copy:
+ movb (%esi), %al
+ movsb
+ cmp $0, %al
+ jne .cmdline_copy
+
+ /* Copy memmap_paddr after cmdline (only if hvm_start_info->version != 0) */
+ xorl %eax, %eax
+ cmpl START_INFO_VERSION(%ebx), %eax
+ je .reload_ebx
+ movl MMAP_PADDR(%ebx), %esi
+ movl $RELOC(__kernel_end), %ecx
+ movl %edi, MMAP_PADDR(%ecx) /* Set new memmap_paddr in hvm_start_info */
+ movl MMAP_ENTRIES(%ebx), %eax /* Get memmap_entries */
+ movl $MMAP_ENTRY_SIZE, %ebx
+ mull %ebx /* eax * ebx => edx:eax */
+ movl %eax, %ecx
+ shrl $2, %ecx
+ rep movsl
+
+.reload_ebx:
+ movl $RELOC(__kernel_end), %ebx
+
+ /* announce ourself */
+ movl $VM_GUEST_GENPVH, RELOC(vm_guest)
+
+ jmp .save_hvm_start_paddr
+
+.start_xen:
+ pop %ebx
+ movl $VM_GUEST_XENPVH, RELOC(vm_guest)
+
+.save_hvm_start_paddr:
+ /*
+ * save addr of the hvm_start_info structure. This is also the end
+ * of the symbol table
/*
* save addr of the hvm_start_info structure. This is also the end
* of the symbol table
@@ -1226,22 +1314,25 @@ ENTRY(start_xenpvh)
movl $RELOC(esym),%ebp
movl %eax,(%ebp)
/* get a page for HYPERVISOR_shared_info */
+ /* this is only needed if we are running on Xen */
+ cmpl $VM_GUEST_XENPVH, RELOC(vm_guest)
+ jne .add_hvm_start_info_page
addl $PAGE_SIZE, %ebx
addl $PGOFSET,%ebx
andl $~PGOFSET,%ebx
movl $RELOC(HYPERVISOR_shared_info_pa),%ebp
movl %ebx,(%ebp)
/* XXX assume hvm_start_info+dependant structure fits in a single page */
+.add_hvm_start_info_page:
addl $PAGE_SIZE, %ebx
addl $PGOFSET,%ebx
andl $~PGOFSET,%ebx
addl $KERNBASE,%ebx
movl $RELOC(eblob),%ebp
movl %ebx,(%ebp)
- /* announce ourself */
- movl $VM_GUEST_XENPVH, RELOC(vm_guest)
+
jmp .Lstart_common
-END(start_xenpvh)
+END(start_pvh)
.align 8
gdtdesc_xenpvh:
.word gdt_xenpvhend - gdt_xenpvh
diff --git a/sys/arch/i386/i386/machdep.c b/sys/arch/i386/i386/machdep.c
index 8a0d395421b..6366a533133 100644
--- a/sys/arch/i386/i386/machdep.c
+++ b/sys/arch/i386/i386/machdep.c
@@ -1105,6 +1105,11 @@ init386_ksyms(void)
return;
#endif
+ if (vm_guest == VM_GUEST_GENPVH) {
+ ksyms_addsyms_elf(0, ((int *)&end) + 1, esym);
+ return;
+ }
+
if ((symtab = lookup_bootinfo(BTINFO_SYMTAB)) == NULL) {
ksyms_addsyms_elf(*(int *)&end, ((int *)&end) + 1, esym);
return;
@@ -1184,7 +1189,7 @@ init386(paddr_t first_avail)
#endif
#ifdef XEN
- if (vm_guest == VM_GUEST_XENPVH)
+ if (vm_guest == VM_GUEST_XENPVH || vm_guest == VM_GUEST_GENPVH)
xen_parse_cmdline(XEN_PARSE_BOOTFLAGS, NULL);
#endif