We need to adjust virtual address space to support switching between
paging modes.

The adjustment happens in __startup_64().

We also have to change KASLR code that doesn't expect variable
VMALLOC_SIZE_TB.

Signed-off-by: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
---
 arch/x86/boot/compressed/kaslr.c        | 14 ++++++++--
 arch/x86/include/asm/page_64_types.h    |  9 ++----
 arch/x86/include/asm/pgtable_64_types.h | 25 +++++++++--------
 arch/x86/kernel/head64.c                | 49 +++++++++++++++++++++++++++------
 arch/x86/kernel/head_64.S               |  2 +-
 arch/x86/mm/dump_pagetables.c           |  3 ++
 arch/x86/mm/kaslr.c                     | 11 ++++----
 7 files changed, 77 insertions(+), 36 deletions(-)

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index b18e8f9512de..66e42a098d70 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -47,9 +47,9 @@
 #include <linux/decompress/mm.h>
 
 #ifdef CONFIG_X86_5LEVEL
-unsigned int pgtable_l5_enabled __ro_after_init = 1;
-unsigned int pgdir_shift __ro_after_init = 48;
-unsigned int ptrs_per_p4d __ro_after_init = 512;
+unsigned int pgtable_l5_enabled __ro_after_init;
+unsigned int pgdir_shift __ro_after_init = 39;
+unsigned int ptrs_per_p4d __ro_after_init = 1;
 #endif
 
 extern unsigned long get_cmd_line_ptr(void);
@@ -729,6 +729,14 @@ void choose_random_location(unsigned long input,
                return;
        }
 
+#ifdef CONFIG_X86_5LEVEL
+       if (__read_cr4() & X86_CR4_LA57) {
+               pgtable_l5_enabled = 1;
+               pgdir_shift = 48;
+               ptrs_per_p4d = 512;
+       }
+#endif
+
        boot_params->hdr.loadflags |= KASLR_FLAG;
 
        /* Prepare to add new identity pagetables on demand. */
diff --git a/arch/x86/include/asm/page_64_types.h 
b/arch/x86/include/asm/page_64_types.h
index fa7dc7cd8c19..2c5a966dc222 100644
--- a/arch/x86/include/asm/page_64_types.h
+++ b/arch/x86/include/asm/page_64_types.h
@@ -37,16 +37,13 @@
  * hypervisor to fit.  Choosing 16 slots here is arbitrary, but it's
  * what Xen requires.
  */
-#ifdef CONFIG_X86_5LEVEL
-#define __PAGE_OFFSET_BASE      _AC(0xff10000000000000, UL)
-#else
-#define __PAGE_OFFSET_BASE      _AC(0xffff880000000000, UL)
-#endif
+#define __PAGE_OFFSET_BASE_L5  _AC(0xff10000000000000, UL)
+#define __PAGE_OFFSET_BASE_L4  _AC(0xffff880000000000, UL)
 
 #ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT
 #define __PAGE_OFFSET           page_offset_base
 #else
-#define __PAGE_OFFSET           __PAGE_OFFSET_BASE
+#define __PAGE_OFFSET           __PAGE_OFFSET_BASE_L4
 #endif /* CONFIG_DYNAMIC_MEMORY_LAYOUT */
 
 #define __START_KERNEL_map     _AC(0xffffffff80000000, UL)
diff --git a/arch/x86/include/asm/pgtable_64_types.h 
b/arch/x86/include/asm/pgtable_64_types.h
index 59d971c85de5..68909a68e5b9 100644
--- a/arch/x86/include/asm/pgtable_64_types.h
+++ b/arch/x86/include/asm/pgtable_64_types.h
@@ -102,25 +102,26 @@ extern unsigned int ptrs_per_p4d;
 #define LDT_PGD_ENTRY          (pgtable_l5_enabled ? LDT_PGD_ENTRY_L5 : 
LDT_PGD_ENTRY_L4)
 #define LDT_BASE_ADDR          (LDT_PGD_ENTRY << PGDIR_SHIFT)
 
-#ifdef CONFIG_X86_5LEVEL
-# define VMALLOC_SIZE_TB       _AC(12800, UL)
-# define __VMALLOC_BASE                _AC(0xffa0000000000000, UL)
-# define __VMEMMAP_BASE                _AC(0xffd4000000000000, UL)
-#else
-# define VMALLOC_SIZE_TB       _AC(32, UL)
-# define __VMALLOC_BASE                _AC(0xffffc90000000000, UL)
-# define __VMEMMAP_BASE                _AC(0xffffea0000000000, UL)
-#endif
+#define __VMALLOC_BASE_L4      0xffffc90000000000
+#define __VMALLOC_BASE_L5      0xffa0000000000000
+
+#define VMALLOC_SIZE_TB_L4     32UL
+#define VMALLOC_SIZE_TB_L5     12800UL
+
+#define __VMEMMAP_BASE_L4      0xffffea0000000000
+#define __VMEMMAP_BASE_L5      0xffd4000000000000
 
 #ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT
 # define VMALLOC_START         vmalloc_base
+# define VMALLOC_SIZE_TB       (pgtable_l5_enabled ? VMALLOC_SIZE_TB_L5 : 
VMALLOC_SIZE_TB_L4)
 # define VMEMMAP_START         vmemmap_base
 #else
-# define VMALLOC_START         __VMALLOC_BASE
-# define VMEMMAP_START         __VMEMMAP_BASE
+# define VMALLOC_START         __VMALLOC_BASE_L4
+# define VMALLOC_SIZE_TB       VMALLOC_SIZE_TB_L4
+# define VMEMMAP_START         __VMEMMAP_BASE_L4
 #endif /* CONFIG_DYNAMIC_MEMORY_LAYOUT */
 
-#define VMALLOC_END            (VMALLOC_START + _AC((VMALLOC_SIZE_TB << 40) - 
1, UL))
+#define VMALLOC_END            (VMALLOC_START + (VMALLOC_SIZE_TB << 40) - 1)
 
 #define MODULES_VADDR          (__START_KERNEL_map + KERNEL_IMAGE_SIZE)
 /* The module sections ends with the start of the fixmap */
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 98b0ff49b220..795e762f3c66 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -40,20 +40,20 @@ static unsigned int __initdata next_early_pgt;
 pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX);
 
 #ifdef CONFIG_X86_5LEVEL
-unsigned int pgtable_l5_enabled __ro_after_init = 1;
+unsigned int pgtable_l5_enabled __ro_after_init;
 EXPORT_SYMBOL(pgtable_l5_enabled);
-unsigned int pgdir_shift __ro_after_init = 48;
+unsigned int pgdir_shift __ro_after_init = 39;
 EXPORT_SYMBOL(pgdir_shift);
-unsigned int ptrs_per_p4d __ro_after_init = 512;
+unsigned int ptrs_per_p4d __ro_after_init = 1;
 EXPORT_SYMBOL(ptrs_per_p4d);
 #endif
 
 #ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT
-unsigned long page_offset_base __ro_after_init = __PAGE_OFFSET_BASE;
+unsigned long page_offset_base __ro_after_init = __PAGE_OFFSET_BASE_L4;
 EXPORT_SYMBOL(page_offset_base);
-unsigned long vmalloc_base __ro_after_init = __VMALLOC_BASE;
+unsigned long vmalloc_base __ro_after_init = __VMALLOC_BASE_L4;
 EXPORT_SYMBOL(vmalloc_base);
-unsigned long vmemmap_base __ro_after_init = __VMEMMAP_BASE;
+unsigned long vmemmap_base __ro_after_init = __VMEMMAP_BASE_L4;
 EXPORT_SYMBOL(vmemmap_base);
 #endif
 
@@ -64,10 +64,40 @@ static void __head *fixup_pointer(void *ptr, unsigned long 
physaddr)
        return ptr - (void *)_text + (void *)physaddr;
 }
 
+static unsigned long __head *fixup_long(void *ptr, unsigned long physaddr)
+{
+       return fixup_pointer(ptr, physaddr);
+}
+
+#ifdef CONFIG_X86_5LEVEL
+static unsigned int __head *fixup_int(void *ptr, unsigned long physaddr)
+{
+       return fixup_pointer(ptr, physaddr);
+}
+
+static void __head check_la57_support(unsigned long physaddr)
+{
+       if (native_cpuid_eax(0) < 7)
+               return;
+
+       if (!(native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31))))
+               return;
+
+       *fixup_int(&pgtable_l5_enabled, physaddr) = 1;
+       *fixup_int(&pgdir_shift, physaddr) = 48;
+       *fixup_int(&ptrs_per_p4d, physaddr) = 512;
+       *fixup_long(&page_offset_base, physaddr) = __PAGE_OFFSET_BASE_L5;
+       *fixup_long(&vmalloc_base, physaddr) = __VMALLOC_BASE_L5;
+       *fixup_long(&vmemmap_base, physaddr) = __VMEMMAP_BASE_L5;
+}
+#else
+static void __head check_la57_support(unsigned long physaddr) {}
+#endif
+
 unsigned long __head __startup_64(unsigned long physaddr,
                                  struct boot_params *bp)
 {
-       unsigned long load_delta, *p;
+       unsigned long load_delta;
        unsigned long pgtable_flags;
        pgdval_t *pgd;
        p4dval_t *p4d;
@@ -76,6 +106,8 @@ unsigned long __head __startup_64(unsigned long physaddr,
        int i;
        unsigned int *next_pgt_ptr;
 
+       check_la57_support(physaddr);
+
        /* Is the address too large? */
        if (physaddr >> MAX_PHYSMEM_BITS)
                for (;;);
@@ -172,8 +204,7 @@ unsigned long __head __startup_64(unsigned long physaddr,
         * Fixup phys_base - remove the memory encryption mask to obtain
         * the true physical address.
         */
-       p = fixup_pointer(&phys_base, physaddr);
-       *p += load_delta - sme_get_me_mask();
+       *fixup_long(&phys_base, physaddr) += load_delta - sme_get_me_mask();
 
        /* Encrypt the kernel and related (if SME is active) */
        sme_encrypt_kernel(bp);
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 04a625f0fcda..d3f8b43d541a 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -41,7 +41,7 @@
 #define pud_index(x)   (((x) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
 
 #if defined(CONFIG_XEN_PV) || defined(CONFIG_XEN_PVH)
-PGD_PAGE_OFFSET = pgd_index(__PAGE_OFFSET_BASE)
+PGD_PAGE_OFFSET = pgd_index(__PAGE_OFFSET_BASE_L4)
 PGD_START_KERNEL = pgd_index(__START_KERNEL_map)
 #endif
 L3_START_KERNEL = pud_index(__START_KERNEL_map)
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 9efee6f464ab..a32f0621d664 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -579,6 +579,9 @@ static int __init pt_dump_init(void)
        address_markers[KASAN_SHADOW_START_NR].start_address = 
KASAN_SHADOW_START;
        address_markers[KASAN_SHADOW_END_NR].start_address = KASAN_SHADOW_END;
 #endif
+#ifdef CONFIG_MODIFY_LDT_SYSCALL
+        address_markers[LDT_NR].start_address = LDT_BASE_ADDR;
+#endif
 #endif
 #ifdef CONFIG_X86_32
        address_markers[VMALLOC_START_NR].start_address = VMALLOC_START;
diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
index d079878c6cbc..641169d38184 100644
--- a/arch/x86/mm/kaslr.c
+++ b/arch/x86/mm/kaslr.c
@@ -34,13 +34,10 @@
 #define TB_SHIFT 40
 
 /*
- * Virtual address start and end range for randomization.
- *
  * The end address could depend on more configuration options to make the
  * highest amount of space for randomization available, but that's too hard
  * to keep straight and caused issues already.
  */
-static const unsigned long vaddr_start = __PAGE_OFFSET_BASE;
 static const unsigned long vaddr_end = CPU_ENTRY_AREA_BASE;
 
 /*
@@ -53,7 +50,7 @@ static __initdata struct kaslr_memory_region {
        unsigned long size_tb;
 } kaslr_regions[] = {
        { &page_offset_base, 0 },
-       { &vmalloc_base, VMALLOC_SIZE_TB },
+       { &vmalloc_base, 0 },
        { &vmemmap_base, 1 },
 };
 
@@ -76,11 +73,14 @@ static inline bool kaslr_memory_enabled(void)
 void __init kernel_randomize_memory(void)
 {
        size_t i;
-       unsigned long vaddr = vaddr_start;
+       unsigned long vaddr_start, vaddr;
        unsigned long rand, memory_tb;
        struct rnd_state rand_state;
        unsigned long remain_entropy;
 
+       vaddr_start = pgtable_l5_enabled ? __PAGE_OFFSET_BASE_L5 : 
__PAGE_OFFSET_BASE_L4;
+       vaddr = vaddr_start;
+
        /*
         * These BUILD_BUG_ON checks ensure the memory layout is consistent
         * with the vaddr_start/vaddr_end variables. These checks are very
@@ -94,6 +94,7 @@ void __init kernel_randomize_memory(void)
                return;
 
        kaslr_regions[0].size_tb = 1 << (__PHYSICAL_MASK_SHIFT - TB_SHIFT);
+       kaslr_regions[1].size_tb = VMALLOC_SIZE_TB;
 
        /*
         * Update Physical memory mapping to available and
-- 
2.15.1

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