x86/boot changes for v4.7

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index b68e3033e6b9..73ccf63b0f48 100644
@@ -15,9 +15,9 @@ static inline char rdfs8(addr_t addr)
 #include "../cmdline.c"
 static unsigned long get_cmd_line_ptr(void)
 {
-	unsigned long cmd_line_ptr = real_mode->hdr.cmd_line_ptr;
+	unsigned long cmd_line_ptr = boot_params->hdr.cmd_line_ptr;
 
-	cmd_line_ptr |= (u64)real_mode->ext_cmd_line_ptr << 32;
+	cmd_line_ptr |= (u64)boot_params->ext_cmd_line_ptr << 32;
 
 	return cmd_line_ptr;
 }

new file mode 100644
index 000000000000..6248740b68b5
@@ -0,0 +1,22 @@
+/*
+ * Callers outside of misc.c need access to the error reporting routines,
+ * but the *_putstr() functions need to stay in misc.c because of how
+ * memcpy() and memmove() are defined for the compressed boot environment.
+ */
+#include "misc.h"
+
+void warn(char *m)
+{
+	error_putstr("\n\n");
+	error_putstr(m);
+	error_putstr("\n\n");
+}
+
+void error(char *m)
+{
+	warn(m);
+	error_putstr(" -- System halted");
+
+	while (1)
+		asm("hlt");
+}

new file mode 100644
index 000000000000..2e59dac07f9e
@@ -0,0 +1,7 @@
+#ifndef BOOT_COMPRESSED_ERROR_H
+#define BOOT_COMPRESSED_ERROR_H
+
+void warn(char *m);
+void error(char *m);
+
+#endif /* BOOT_COMPRESSED_ERROR_H */

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index 3783dc3e10b3..b6fec1ff10e4 100644
@@ -32,7 +32,7 @@
 /* misc.c */
 extern memptr free_mem_ptr;
 extern memptr free_mem_end_ptr;
-extern struct boot_params *real_mode;		/* Pointer to real-mode data */
+extern struct boot_params *boot_params;
 void __putstr(const char *s);
 void __puthex(unsigned long value);
 #define error_putstr(__x)  __putstr(__x)

@@ -66,26 +66,35 @@ int cmdline_find_option_bool(const char *option);
 
 
 #if CONFIG_RANDOMIZE_BASE
-/* aslr.c */
-unsigned char *choose_kernel_location(struct boot_params *boot_params,
-				      unsigned char *input,
+/* kaslr.c */
+unsigned char *choose_random_location(unsigned long input_ptr,
 				      unsigned long input_size,
-				      unsigned char *output,
+				      unsigned long output_ptr,
 				      unsigned long output_size);
 /* cpuflags.c */
 bool has_cpuflag(int flag);
 #else
 static inline
-unsigned char *choose_kernel_location(struct boot_params *boot_params,
-				      unsigned char *input,
+unsigned char *choose_random_location(unsigned long input_ptr,
 				      unsigned long input_size,
-				      unsigned char *output,
+				      unsigned long output_ptr,
 				      unsigned long output_size)
 {
-	return output;
+	return (unsigned char *)output_ptr;
 }
 #endif
 
+#ifdef CONFIG_X86_64
+void add_identity_map(unsigned long start, unsigned long size);
+void finalize_identity_maps(void);
+extern unsigned char _pgtable[];
+#else
+static inline void add_identity_map(unsigned long start, unsigned long size)
+{ }
+static inline void finalize_identity_maps(void)
+{ }
+#endif
+
 #ifdef CONFIG_EARLY_PRINTK
 /* early_serial_console.c */
 extern int early_serial_base;

index d8222f213182..72bad2c8debe 100644
@@ -18,11 +18,10 @@
  *
  *  H. Peter Anvin <[email protected]>
  *
- * ----------------------------------------------------------------------- */
-
-/*
- * Compute the desired load offset from a compressed program; outputs
- * a small assembly wrapper with the appropriate symbols defined.
+ * -----------------------------------------------------------------------
+ *
+ * Outputs a small assembly wrapper with the appropriate symbols defined.
+ *
  */
 
 #include <stdlib.h>

@@ -35,14 +34,11 @@ int main(int argc, char *argv[])
 {
 	uint32_t olen;
 	long ilen;
-	unsigned long offs;
-	unsigned long run_size;
 	FILE *f = NULL;
 	int retval = 1;
 
-	if (argc < 3) {
-		fprintf(stderr, "Usage: %s compressed_file run_size\n",
-				argv[0]);
+	if (argc < 2) {
+		fprintf(stderr, "Usage: %s compressed_file\n", argv[0]);
 		goto bail;
 	}
 

@@ -67,29 +63,11 @@ int main(int argc, char *argv[])
 	ilen = ftell(f);
 	olen = get_unaligned_le32(&olen);
 
-	/*
-	 * Now we have the input (compressed) and output (uncompressed)
-	 * sizes, compute the necessary decompression offset...
-	 */
-
-	offs = (olen > ilen) ? olen - ilen : 0;
-	offs += olen >> 12;	/* Add 8 bytes for each 32K block */
-	offs += 64*1024 + 128;	/* Add 64K + 128 bytes slack */
-	offs = (offs+4095) & ~4095; /* Round to a 4K boundary */
-	run_size = atoi(argv[2]);
-
 	printf(".section \".rodata..compressed\",\"a\",@progbits\n");
 	printf(".globl z_input_len\n");
 	printf("z_input_len = %lu\n", ilen);
 	printf(".globl z_output_len\n");
 	printf("z_output_len = %lu\n", (unsigned long)olen);
-	printf(".globl z_extract_offset\n");
-	printf("z_extract_offset = 0x%lx\n", offs);
-	/* z_extract_offset_negative allows simplification of head_32.S */
-	printf(".globl z_extract_offset_negative\n");
-	printf("z_extract_offset_negative = -0x%lx\n", offs);
-	printf(".globl z_run_size\n");
-	printf("z_run_size = %lu\n", run_size);
 
 	printf(".globl input_data, input_data_end\n");
 	printf("input_data:\n");

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index 00e788be1db9..cea140ce6b42 100644
@@ -1,7 +1,16 @@
+/*
+ * This provides an optimized implementation of memcpy, and a simplified
+ * implementation of memset and memmove. These are used here because the
+ * standard kernel runtime versions are not yet available and we don't
+ * trust the gcc built-in implementations as they may do unexpected things
+ * (e.g. FPU ops) in the minimal decompression stub execution environment.
+ */
+#include "error.h"
+
 #include "../string.c"
 
 #ifdef CONFIG_X86_32
-void *memcpy(void *dest, const void *src, size_t n)
+static void *__memcpy(void *dest, const void *src, size_t n)
 {
 	int d0, d1, d2;
 	asm volatile(

@@ -15,7 +24,7 @@ void *memcpy(void *dest, const void *src, size_t n)
 	return dest;
 }
 #else
-void *memcpy(void *dest, const void *src, size_t n)
+static void *__memcpy(void *dest, const void *src, size_t n)
 {
 	long d0, d1, d2;
 	asm volatile(

@@ -39,3 +48,27 @@ void *memset(void *s, int c, size_t n)
 		ss[i] = c;
 	return s;
 }
+
+void *memmove(void *dest, const void *src, size_t n)
+{
+	unsigned char *d = dest;
+	const unsigned char *s = src;
+
+	if (d <= s || d - s >= n)
+		return __memcpy(dest, src, n);
+
+	while (n-- > 0)
+		d[n] = s[n];
+
+	return dest;
+}
+
+/* Detect and warn about potential overlaps, but handle them with memmove. */
+void *memcpy(void *dest, const void *src, size_t n)
+{
+	if (dest > src && dest - src < n) {
+		warn("Avoiding potentially unsafe overlapping memcpy()!");
+		return memmove(dest, src, n);
+	}
+	return __memcpy(dest, src, n);
+}

index 45a07684bbab..f0b8d6d93164 100644
@@ -1,3 +1,7 @@
+/*
+ * Serial port routines for use during early boot reporting. This code is
+ * included from both the compressed kernel and the regular kernel.
+ */
 #include "boot.h"
 
 #define DEFAULT_SERIAL_PORT 0x3f8 /* ttyS0 */

index 6b8d6e8cd449..abd06b19ddd2 100644
@@ -12,29 +12,46 @@
 
 /* Minimum kernel alignment, as a power of two */
 #ifdef CONFIG_X86_64
-#define MIN_KERNEL_ALIGN_LG2	PMD_SHIFT
+# define MIN_KERNEL_ALIGN_LG2	PMD_SHIFT
 #else
-#define MIN_KERNEL_ALIGN_LG2	(PAGE_SHIFT + THREAD_SIZE_ORDER)
+# define MIN_KERNEL_ALIGN_LG2	(PAGE_SHIFT + THREAD_SIZE_ORDER)
 #endif
 #define MIN_KERNEL_ALIGN	(_AC(1, UL) << MIN_KERNEL_ALIGN_LG2)
 
 #if (CONFIG_PHYSICAL_ALIGN & (CONFIG_PHYSICAL_ALIGN-1)) || \
 	(CONFIG_PHYSICAL_ALIGN < MIN_KERNEL_ALIGN)
-#error "Invalid value for CONFIG_PHYSICAL_ALIGN"
+# error "Invalid value for CONFIG_PHYSICAL_ALIGN"
 #endif
 
 #ifdef CONFIG_KERNEL_BZIP2
-#define BOOT_HEAP_SIZE             0x400000
+# define BOOT_HEAP_SIZE		0x400000
 #else /* !CONFIG_KERNEL_BZIP2 */
-
-#define BOOT_HEAP_SIZE	0x10000
-
-#endif /* !CONFIG_KERNEL_BZIP2 */
+# define BOOT_HEAP_SIZE		 0x10000
+#endif
 
 #ifdef CONFIG_X86_64
-#define BOOT_STACK_SIZE	0x4000
-#else
-#define BOOT_STACK_SIZE	0x1000
+# define BOOT_STACK_SIZE	0x4000
+
+# define BOOT_INIT_PGT_SIZE	(6*4096)
+# ifdef CONFIG_RANDOMIZE_BASE
+/*
+ * Assuming all cross the 512GB boundary:
+ * 1 page for level4
+ * (2+2)*4 pages for kernel, param, cmd_line, and randomized kernel
+ * 2 pages for first 2M (video RAM: CONFIG_X86_VERBOSE_BOOTUP).
+ * Total is 19 pages.
+ */
+#  ifdef CONFIG_X86_VERBOSE_BOOTUP
+#   define BOOT_PGT_SIZE	(19*4096)
+#  else /* !CONFIG_X86_VERBOSE_BOOTUP */
+#   define BOOT_PGT_SIZE	(17*4096)
+#  endif
+# else /* !CONFIG_RANDOMIZE_BASE */
+#  define BOOT_PGT_SIZE		BOOT_INIT_PGT_SIZE
+# endif
+
+#else /* !CONFIG_X86_64 */
+# define BOOT_STACK_SIZE	0x1000
 #endif
 
 #endif /* _ASM_X86_BOOT_H */

index 802dde30c928..cf8f619b305f 100644
@@ -37,7 +37,10 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
 	alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr)
 #define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
 
+#ifndef __pa
 #define __pa(x)		__phys_addr((unsigned long)(x))
+#endif
+
 #define __pa_nodebug(x)	__phys_addr_nodebug((unsigned long)(x))
 /* __pa_symbol should be used for C visible symbols.
    This seems to be the official gcc blessed way to do such arithmetic. */

@@ -51,7 +54,9 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
 #define __pa_symbol(x) \
 	__phys_addr_symbol(__phys_reloc_hide((unsigned long)(x)))
 
+#ifndef __va
 #define __va(x)			((void *)((unsigned long)(x)+PAGE_OFFSET))
+#endif
 
 #define __boot_va(x)		__va(x)
 #define __boot_pa(x)		__pa(x)

index 4928cf0d5af0..d5c2f8b40faa 100644
@@ -47,12 +47,10 @@
  * are fully set up. If kernel ASLR is configured, it can extend the
  * kernel page table mapping, reducing the size of the modules area.
  */
-#define KERNEL_IMAGE_SIZE_DEFAULT      (512 * 1024 * 1024)
-#if defined(CONFIG_RANDOMIZE_BASE) && \
-	CONFIG_RANDOMIZE_BASE_MAX_OFFSET > KERNEL_IMAGE_SIZE_DEFAULT
-#define KERNEL_IMAGE_SIZE   CONFIG_RANDOMIZE_BASE_MAX_OFFSET
+#if defined(CONFIG_RANDOMIZE_BASE)
+#define KERNEL_IMAGE_SIZE	(1024 * 1024 * 1024)
 #else
-#define KERNEL_IMAGE_SIZE      KERNEL_IMAGE_SIZE_DEFAULT
+#define KERNEL_IMAGE_SIZE	(512 * 1024 * 1024)
 #endif
 
 #endif /* _ASM_X86_PAGE_64_DEFS_H */

index 601f1b8f9961..dff26bc91b17 100644
@@ -15,17 +15,6 @@
 #include <linux/cpumask.h>
 #include <asm/frame.h>
 
-static inline int paravirt_enabled(void)
-{
-	return pv_info.paravirt_enabled;
-}
-
-static inline int paravirt_has_feature(unsigned int feature)
-{
-	WARN_ON_ONCE(!pv_info.paravirt_enabled);
-	return (pv_info.features & feature);
-}
-
 static inline void load_sp0(struct tss_struct *tss,
 			     struct thread_struct *thread)
 {

index e8c2326478c8..7fedf24bd811 100644
@@ -69,15 +69,9 @@ struct pv_info {
 	u16 extra_user_64bit_cs;  /* __USER_CS if none */
 #endif
 
-	int paravirt_enabled;
-	unsigned int features;	  /* valid only if paravirt_enabled is set */
 	const char *name;
 };
 
-#define paravirt_has(x) paravirt_has_feature(PV_SUPPORTED_##x)
-/* Supported features */
-#define PV_SUPPORTED_RTC        (1<<0)
-
 struct pv_init_ops {
 	/*
 	 * Patch may replace one of the defined code sequences with

index 9264476f3d57..8d326e822cb8 100644
@@ -473,8 +473,6 @@ static inline unsigned long current_top_of_stack(void)
 #include <asm/paravirt.h>
 #else
 #define __cpuid			native_cpuid
-#define paravirt_enabled()	0
-#define paravirt_has(x) 	0
 
 static inline void load_sp0(struct tss_struct *tss,
 			    struct thread_struct *thread)

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index 8c2f1ef6ca23..c9a06e573fa5 100644
@@ -913,6 +913,15 @@ late_initcall(hpet_insert_resource);
 
 static int __init acpi_parse_fadt(struct acpi_table_header *table)
 {
+	if (!(acpi_gbl_FADT.boot_flags & ACPI_FADT_LEGACY_DEVICES)) {
+		pr_debug("ACPI: no legacy devices present\n");
+		x86_platform.legacy.devices.pnpbios = 0;
+	}
+
+	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_CMOS_RTC) {
+		pr_debug("ACPI: not registering RTC platform device\n");
+		x86_platform.legacy.rtc = 0;
+	}
 
 #ifdef CONFIG_X86_PM_TIMER
 	/* detect the location of the ACPI PM Timer */

index 9307f182fe30..c7364bd633e1 100644
@@ -2267,7 +2267,7 @@ static int __init apm_init(void)
 
 	dmi_check_system(apm_dmi_table);
 
-	if (apm_info.bios.version == 0 || paravirt_enabled() || machine_is_olpc()) {
+	if (apm_info.bios.version == 0 || machine_is_olpc()) {
 		printk(KERN_INFO "apm: BIOS not found.\n");
 		return -ENODEV;
 	}

index 5c042466f274..674134e9f5e5 100644
@@ -80,6 +80,7 @@ void common(void) {
 	OFFSET(BP_hardware_subarch, boot_params, hdr.hardware_subarch);
 	OFFSET(BP_version, boot_params, hdr.version);
 	OFFSET(BP_kernel_alignment, boot_params, hdr.kernel_alignment);
+	OFFSET(BP_init_size, boot_params, hdr.init_size);
 	OFFSET(BP_pref_address, boot_params, hdr.pref_address);
 	OFFSET(BP_code32_start, boot_params, hdr.code32_start);
 

index 1f7fdb91a818..016b3d9ffa7d 100644
@@ -233,7 +233,7 @@ static void intel_workarounds(struct cpuinfo_x86 *c)
 	 * The Quark is also family 5, but does not have the same bug.
 	 */
 	clear_cpu_bug(c, X86_BUG_F00F);
-	if (!paravirt_enabled() && c->x86 == 5 && c->x86_model < 9) {
+	if (c->x86 == 5 && c->x86_model < 9) {
 		static int f00f_workaround_enabled;
 
 		set_cpu_bug(c, X86_BUG_F00F);

similarity index 98%
rename from arch/x86/kernel/head.c
rename to arch/x86/kernel/ebda.c
index 992f442ca155..afe65dffee80 100644
@@ -38,7 +38,7 @@ void __init reserve_ebda_region(void)
 	 * that the paravirt case can handle memory setup
 	 * correctly, without our help.
 	 */
-	if (paravirt_enabled())
+	if (!x86_platform.legacy.ebda_search)
 		return;
 
 	/* end of low (conventional) memory */

index 2911ef3a9f1c..d784bb547a9d 100644
@@ -34,6 +34,8 @@ asmlinkage __visible void __init i386_start_kernel(void)
 	cr4_init_shadow();
 	sanitize_boot_params(&boot_params);
 
+	x86_early_init_platform_quirks();
+
 	/* Call the subarch specific early setup function */
 	switch (boot_params.hdr.hardware_subarch) {
 	case X86_SUBARCH_INTEL_MID:

index 1f4422d5c8d0..b72fb0b71dd1 100644
@@ -182,6 +182,7 @@ void __init x86_64_start_reservations(char *real_mode_data)
 	if (!boot_params.hdr.version)
 		copy_bootdata(__va(real_mode_data));
 
+	x86_early_init_platform_quirks();
 	reserve_ebda_region();
 
 	switch (boot_params.hdr.hardware_subarch) {

index 807950860fb7..c66546f29b81 100644
@@ -285,14 +285,6 @@ static void __init paravirt_ops_setup(void)
 {
 	pv_info.name = "KVM";
 
-	/*
-	 * KVM isn't paravirt in the sense of paravirt_enabled.  A KVM
-	 * guest kernel works like a bare metal kernel with additional
-	 * features, and paravirt_enabled is about features that are
-	 * missing.
-	 */
-	pv_info.paravirt_enabled = 0;
-
 	if (kvm_para_has_feature(KVM_FEATURE_NOP_IO_DELAY))
 		pv_cpu_ops.io_delay = kvm_io_delay;
 

index f08ac28b8136..71a2d8a05a66 100644
@@ -294,7 +294,6 @@ enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
 
 struct pv_info pv_info = {
 	.name = "bare hardware",
-	.paravirt_enabled = 0,
 	.kernel_rpl = 0,
 	.shared_kernel_pmd = 1,	/* Only used when CONFIG_X86_PAE is set */
 

new file mode 100644
index 000000000000..b2f8a33b36ff
@@ -0,0 +1,35 @@
+#include <linux/kernel.h>
+#include <linux/init.h>
+
+#include <asm/setup.h>
+#include <asm/bios_ebda.h>
+
+void __init x86_early_init_platform_quirks(void)
+{
+	x86_platform.legacy.rtc = 1;
+	x86_platform.legacy.ebda_search = 0;
+	x86_platform.legacy.devices.pnpbios = 1;
+
+	switch (boot_params.hdr.hardware_subarch) {
+	case X86_SUBARCH_PC:
+		x86_platform.legacy.ebda_search = 1;
+		break;
+	case X86_SUBARCH_XEN:
+	case X86_SUBARCH_LGUEST:
+	case X86_SUBARCH_INTEL_MID:
+	case X86_SUBARCH_CE4100:
+		x86_platform.legacy.devices.pnpbios = 0;
+		x86_platform.legacy.rtc = 0;
+		break;
+	}
+
+	if (x86_platform.set_legacy_features)
+		x86_platform.set_legacy_features();
+}
+
+#if defined(CONFIG_PNPBIOS)
+bool __init arch_pnpbios_disabled(void)
+{
+	return x86_platform.legacy.devices.pnpbios == 0;
+}
+#endif

index 4af8d063fb36..eceaa082ec3f 100644
@@ -14,6 +14,7 @@
 #include <asm/time.h>
 #include <asm/intel-mid.h>
 #include <asm/rtc.h>
+#include <asm/setup.h>
 
 #ifdef CONFIG_X86_32
 /*

@@ -185,22 +186,7 @@ static __init int add_rtc_cmos(void)
 		}
 	}
 #endif
-	if (of_have_populated_dt())
-		return 0;
-
-	/* Intel MID platforms don't have ioport rtc */
-	if (intel_mid_identify_cpu())
-		return -ENODEV;
-
-#ifdef CONFIG_ACPI
-	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_CMOS_RTC) {
-		/* This warning can likely go away again in a year or two. */
-		pr_info("ACPI: not registering RTC platform device\n");
-		return -ENODEV;
-	}
-#endif
-
-	if (paravirt_enabled() && !paravirt_has(RTC))
+	if (!x86_platform.legacy.rtc)
 		return -ENODEV;
 
 	platform_device_register(&rtc_device);

index e72a07f20b05..9b0185fbe3eb 100644
@@ -74,12 +74,6 @@ void __init tboot_probe(void)
 		return;
 	}
 
-	/* only a natively booted kernel should be using TXT */
-	if (paravirt_enabled()) {
-		pr_warning("non-0 tboot_addr but pv_ops is enabled\n");
-		return;
-	}
-
 	/* Map and check for tboot UUID. */
 	set_fixmap(FIX_TBOOT_BASE, boot_params.tboot_addr);
 	tboot = (struct tboot *)fix_to_virt(FIX_TBOOT_BASE);

index fd57d3ae7e16..3847e736702e 100644
@@ -1408,13 +1408,10 @@ __init void lguest_init(void)
 {
 	/* We're under lguest. */
 	pv_info.name = "lguest";
-	/* Paravirt is enabled. */
-	pv_info.paravirt_enabled = 1;
 	/* We're running at privilege level 1, not 0 as normal. */
 	pv_info.kernel_rpl = 1;
 	/* Everyone except Xen runs with this set. */
 	pv_info.shared_kernel_pmd = 1;
-	pv_info.features = 0;
 
 	/*
 	 * We set up all the lguest overrides for sensitive operations.  These

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index bd7a9b9e2e14..f2ee42d61894 100644
@@ -804,9 +804,6 @@ void __init mem_init(void)
 	BUILD_BUG_ON(VMALLOC_START			>= VMALLOC_END);
 #undef high_memory
 #undef __FIXADDR_TOP
-#ifdef CONFIG_RANDOMIZE_BASE
-	BUILD_BUG_ON(CONFIG_RANDOMIZE_BASE_MAX_OFFSET > KERNEL_IMAGE_SIZE);
-#endif
 
 #ifdef CONFIG_HIGHMEM
 	BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE	> FIXADDR_START);

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index 880862c7d9dd..5fc20a1108c7 100644
@@ -1187,13 +1187,11 @@ static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
 }
 
 static const struct pv_info xen_info __initconst = {
-	.paravirt_enabled = 1,
 	.shared_kernel_pmd = 0,
 
 #ifdef CONFIG_X86_64
 	.extra_user_64bit_cs = FLAT_USER_CS64,
 #endif
-	.features = 0,
 	.name = "Xen",
 };
 

@@ -1506,6 +1504,11 @@ static void __init xen_pvh_early_guest_init(void)
 }
 #endif    /* CONFIG_XEN_PVH */
 
+static void __init xen_dom0_set_legacy_features(void)
+{
+	x86_platform.legacy.rtc = 1;
+}
+
 /* First C function to be called on Xen boot */
 asmlinkage __visible void __init xen_start_kernel(void)
 {

@@ -1527,8 +1530,6 @@ asmlinkage __visible void __init xen_start_kernel(void)
 
 	/* Install Xen paravirt ops */
 	pv_info = xen_info;
-	if (xen_initial_domain())
-		pv_info.features |= PV_SUPPORTED_RTC;
 	pv_init_ops = xen_init_ops;
 	if (!xen_pvh_domain()) {
 		pv_cpu_ops = xen_cpu_ops;

@@ -1670,6 +1671,7 @@ asmlinkage __visible void __init xen_start_kernel(void)
 	boot_params.hdr.ramdisk_image = initrd_start;
 	boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
 	boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
+	boot_params.hdr.hardware_subarch = X86_SUBARCH_XEN;
 
 	if (!xen_initial_domain()) {
 		add_preferred_console("xenboot", 0, NULL);

@@ -1687,6 +1689,8 @@ asmlinkage __visible void __init xen_start_kernel(void)
 			.u.firmware_info.type = XEN_FW_KBD_SHIFT_FLAGS,
 		};
 
+		x86_platform.set_legacy_features =
+				xen_dom0_set_legacy_features;
 		xen_init_vga(info, xen_start_info->console.dom0.info_size);
 		xen_start_info->console.domU.mfn = 0;
 		xen_start_info->console.domU.evtchn = 0;

index facd43b8516c..81603d99082b 100644
@@ -521,10 +521,11 @@ static int __init pnpbios_init(void)
 	int ret;
 
 	if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
-	    paravirt_enabled()) {
+	    arch_pnpbios_disabled()) {
 		printk(KERN_INFO "PnPBIOS: Disabled\n");
 		return -ENODEV;
 	}
+
 #ifdef CONFIG_PNPACPI
 	if (!acpi_disabled && !pnpacpi_disabled) {
 		pnpbios_disabled = 1;

index 5df733b8f704..2588ca6a9028 100644
@@ -337,9 +337,11 @@ extern struct mutex pnp_res_mutex;
 
 #ifdef CONFIG_PNPBIOS
 extern struct pnp_protocol pnpbios_protocol;
+extern bool arch_pnpbios_disabled(void);
 #define pnp_device_is_pnpbios(dev) ((dev)->protocol == (&pnpbios_protocol))
 #else
 #define pnp_device_is_pnpbios(dev) 0
+#define arch_pnpbios_disabled()	false
 #endif
 
 #ifdef CONFIG_PNPACPI

index 80159e6811c2..d9836c5eb694 100644
@@ -3351,12 +3351,18 @@ int main(int argc, char *argv[])
 	/* Boot protocol version: 2.07 supports the fields for lguest. */
 	boot->hdr.version = 0x207;
 
-	/* The hardware_subarch value of "1" tells the Guest it's an lguest. */
-	boot->hdr.hardware_subarch = 1;
+	/* X86_SUBARCH_LGUEST tells the Guest it's an lguest. */
+	boot->hdr.hardware_subarch = X86_SUBARCH_LGUEST;
 
 	/* Tell the entry path not to try to reload segment registers. */
 	boot->hdr.loadflags |= KEEP_SEGMENTS;
 
+	/* We don't support tboot: */
+	boot->tboot_addr = 0;
+
+	/* Ensure this is 0 to prevent APM from loading: */
+	boot->apm_bios_info.version = 0;
+
 	/* We tell the kernel to initialize the Guest. */
 	tell_kernel(start);