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-rw-r--r--arch/x86/xen/xen-head.S124
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diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+/* Xen-specific pieces of head.S, intended to be included in the right
+ place in head.S */
+
+#ifdef CONFIG_XEN
+
+#include <linux/elfnote.h>
+#include <linux/init.h>
+
+#include <asm/boot.h>
+#include <asm/asm.h>
+#include <asm/msr.h>
+#include <asm/page_types.h>
+#include <asm/percpu.h>
+#include <asm/unwind_hints.h>
+
+#include <xen/interface/elfnote.h>
+#include <xen/interface/features.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/xen-mca.h>
+#include <asm/xen/interface.h>
+
+.pushsection .noinstr.text, "ax"
+ .balign PAGE_SIZE
+SYM_CODE_START(hypercall_page)
+ .rept (PAGE_SIZE / 32)
+ UNWIND_HINT_FUNC
+ ANNOTATE_NOENDBR
+ ANNOTATE_UNRET_SAFE
+ ret
+ /*
+ * Xen will write the hypercall page, and sort out ENDBR.
+ */
+ .skip 31, 0xcc
+ .endr
+
+#define HYPERCALL(n) \
+ .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \
+ .type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32
+#include <asm/xen-hypercalls.h>
+#undef HYPERCALL
+SYM_CODE_END(hypercall_page)
+.popsection
+
+#ifdef CONFIG_XEN_PV
+ __INIT
+SYM_CODE_START(startup_xen)
+ UNWIND_HINT_END_OF_STACK
+ ANNOTATE_NOENDBR
+ cld
+
+ leaq (__end_init_task - PTREGS_SIZE)(%rip), %rsp
+
+ /* Set up %gs.
+ *
+ * The base of %gs always points to fixed_percpu_data. If the
+ * stack protector canary is enabled, it is located at %gs:40.
+ * Note that, on SMP, the boot cpu uses init data section until
+ * the per cpu areas are set up.
+ */
+ movl $MSR_GS_BASE,%ecx
+ movq $INIT_PER_CPU_VAR(fixed_percpu_data),%rax
+ cdq
+ wrmsr
+
+ mov %rsi, %rdi
+ call xen_start_kernel
+SYM_CODE_END(startup_xen)
+ __FINIT
+
+#ifdef CONFIG_XEN_PV_SMP
+.pushsection .text
+SYM_CODE_START(asm_cpu_bringup_and_idle)
+ UNWIND_HINT_END_OF_STACK
+ ENDBR
+
+ call cpu_bringup_and_idle
+SYM_CODE_END(asm_cpu_bringup_and_idle)
+
+SYM_CODE_START(xen_cpu_bringup_again)
+ UNWIND_HINT_FUNC
+ mov %rdi, %rsp
+ UNWIND_HINT_REGS
+ call cpu_bringup_and_idle
+SYM_CODE_END(xen_cpu_bringup_again)
+.popsection
+#endif
+#endif
+
+ ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux")
+ ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6")
+ ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0")
+#ifdef CONFIG_XEN_PV
+ ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __START_KERNEL_map)
+ /* Map the p2m table to a 512GB-aligned user address. */
+ ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M, .quad (PUD_SIZE * PTRS_PER_PUD))
+ ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, _ASM_PTR startup_xen)
+ ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .ascii "!writable_page_tables")
+ ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes")
+ ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID,
+ .quad _PAGE_PRESENT; .quad _PAGE_PRESENT)
+ ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN, .long 1)
+ ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET, _ASM_PTR 0)
+# define FEATURES_PV (1 << XENFEAT_writable_page_tables)
+#else
+# define FEATURES_PV 0
+#endif
+#ifdef CONFIG_XEN_PVH
+# define FEATURES_PVH (1 << XENFEAT_linux_rsdp_unrestricted)
+#else
+# define FEATURES_PVH 0
+#endif
+#ifdef CONFIG_XEN_DOM0
+# define FEATURES_DOM0 (1 << XENFEAT_dom0)
+#else
+# define FEATURES_DOM0 0
+#endif
+ ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page)
+ ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES,
+ .long FEATURES_PV | FEATURES_PVH | FEATURES_DOM0)
+ ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic")
+ ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1)
+
+#endif /*CONFIG_XEN */