Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 PTI preparatory patches from Thomas Gleixner:
 "Todays Advent calendar window contains twentyfour easy to digest
  patches. The original plan was to have twenty three matching the date,
  but a late fixup made that moot.

   - Move the cpu_entry_area mapping out of the fixmap into a separate
     address space. That's necessary because the fixmap becomes too big
     with NRCPUS=8192 and this caused already subtle and hard to
     diagnose failures.

     The top most patch is fresh from today and cures a brain slip of
     that tall grumpy german greybeard, who ignored the intricacies of
     32bit wraparounds.

   - Limit the number of CPUs on 32bit to 64. That's insane big already,
     but at least it's small enough to prevent address space issues with
     the cpu_entry_area map, which have been observed and debugged with
     the fixmap code

   - A few TLB flush fixes in various places plus documentation which of
     the TLB functions should be used for what.

   - Rename the SYSENTER stack to CPU_ENTRY_AREA stack as it is used for
     more than sysenter now and keeping the name makes backtraces
     confusing.

   - Prevent LDT inheritance on exec() by moving it to arch_dup_mmap(),
     which is only invoked on fork().

   - Make vysycall more robust.

   - A few fixes and cleanups of the debug_pagetables code. Check
     PAGE_PRESENT instead of checking the PTE for 0 and a cleanup of the
     C89 initialization of the address hint array which already was out
     of sync with the index enums.

   - Move the ESPFIX init to a different place to prepare for PTI.

   - Several code moves with no functional change to make PTI
     integration simpler and header files less convoluted.

   - Documentation fixes and clarifications"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit
  init: Invoke init_espfix_bsp() from mm_init()
  x86/cpu_entry_area: Move it out of the fixmap
  x86/cpu_entry_area: Move it to a separate unit
  x86/mm: Create asm/invpcid.h
  x86/mm: Put MMU to hardware ASID translation in one place
  x86/mm: Remove hard-coded ASID limit checks
  x86/mm: Move the CR3 construction functions to tlbflush.h
  x86/mm: Add comments to clarify which TLB-flush functions are supposed to flush what
  x86/mm: Remove superfluous barriers
  x86/mm: Use __flush_tlb_one() for kernel memory
  x86/microcode: Dont abuse the TLB-flush interface
  x86/uv: Use the right TLB-flush API
  x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack
  x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation
  x86/mm/64: Improve the memory map documentation
  x86/ldt: Prevent LDT inheritance on exec
  x86/ldt: Rework locking
  arch, mm: Allow arch_dup_mmap() to fail
  x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode
  ...

1 files changed, 59 insertions, 39 deletions

diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 5e3ac6fe6c9e..43dedbfb7257 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -44,10 +44,12 @@ struct addr_marker {
 	unsigned long max_lines;
 };
 
-/* indices for address_markers; keep sync'd w/ address_markers below */
+/* Address space markers hints */
+
+#ifdef CONFIG_X86_64
+
 enum address_markers_idx {
 	USER_SPACE_NR = 0,
-#ifdef CONFIG_X86_64
 	KERNEL_SPACE_NR,
 	LOW_KERNEL_NR,
 	VMALLOC_START_NR,
@@ -56,56 +58,74 @@ enum address_markers_idx {
 	KASAN_SHADOW_START_NR,
 	KASAN_SHADOW_END_NR,
 #endif
-# ifdef CONFIG_X86_ESPFIX64
+	CPU_ENTRY_AREA_NR,
+#ifdef CONFIG_X86_ESPFIX64
 	ESPFIX_START_NR,
-# endif
+#endif
+#ifdef CONFIG_EFI
+	EFI_END_NR,
+#endif
 	HIGH_KERNEL_NR,
 	MODULES_VADDR_NR,
 	MODULES_END_NR,
-#else
+	FIXADDR_START_NR,
+	END_OF_SPACE_NR,
+};
+
+static struct addr_marker address_markers[] = {
+	[USER_SPACE_NR]		= { 0,			"User Space" },
+	[KERNEL_SPACE_NR]	= { (1UL << 63),	"Kernel Space" },
+	[LOW_KERNEL_NR]		= { 0UL,		"Low Kernel Mapping" },
+	[VMALLOC_START_NR]	= { 0UL,		"vmalloc() Area" },
+	[VMEMMAP_START_NR]	= { 0UL,		"Vmemmap" },
+#ifdef CONFIG_KASAN
+	[KASAN_SHADOW_START_NR]	= { KASAN_SHADOW_START,	"KASAN shadow" },
+	[KASAN_SHADOW_END_NR]	= { KASAN_SHADOW_END,	"KASAN shadow end" },
+#endif
+	[CPU_ENTRY_AREA_NR]	= { CPU_ENTRY_AREA_BASE,"CPU entry Area" },
+#ifdef CONFIG_X86_ESPFIX64
+	[ESPFIX_START_NR]	= { ESPFIX_BASE_ADDR,	"ESPfix Area", 16 },
+#endif
+#ifdef CONFIG_EFI
+	[EFI_END_NR]		= { EFI_VA_END,		"EFI Runtime Services" },
+#endif
+	[HIGH_KERNEL_NR]	= { __START_KERNEL_map,	"High Kernel Mapping" },
+	[MODULES_VADDR_NR]	= { MODULES_VADDR,	"Modules" },
+	[MODULES_END_NR]	= { MODULES_END,	"End Modules" },
+	[FIXADDR_START_NR]	= { FIXADDR_START,	"Fixmap Area" },
+	[END_OF_SPACE_NR]	= { -1,			NULL }
+};
+
+#else /* CONFIG_X86_64 */
+
+enum address_markers_idx {
+	USER_SPACE_NR = 0,
 	KERNEL_SPACE_NR,
 	VMALLOC_START_NR,
 	VMALLOC_END_NR,
-# ifdef CONFIG_HIGHMEM
+#ifdef CONFIG_HIGHMEM
 	PKMAP_BASE_NR,
-# endif
-	FIXADDR_START_NR,
 #endif
+	CPU_ENTRY_AREA_NR,
+	FIXADDR_START_NR,
+	END_OF_SPACE_NR,
 };
 
-/* Address space markers hints */
 static struct addr_marker address_markers[] = {
-	{ 0, "User Space" },
-#ifdef CONFIG_X86_64
-	{ 0x8000000000000000UL, "Kernel Space" },
-	{ 0/* PAGE_OFFSET */,   "Low Kernel Mapping" },
-	{ 0/* VMALLOC_START */, "vmalloc() Area" },
-	{ 0/* VMEMMAP_START */, "Vmemmap" },
-#ifdef CONFIG_KASAN
-	{ KASAN_SHADOW_START,	"KASAN shadow" },
-	{ KASAN_SHADOW_END,	"KASAN shadow end" },
+	[USER_SPACE_NR]		= { 0,			"User Space" },
+	[KERNEL_SPACE_NR]	= { PAGE_OFFSET,	"Kernel Mapping" },
+	[VMALLOC_START_NR]	= { 0UL,		"vmalloc() Area" },
+	[VMALLOC_END_NR]	= { 0UL,		"vmalloc() End" },
+#ifdef CONFIG_HIGHMEM
+	[PKMAP_BASE_NR]		= { 0UL,		"Persistent kmap() Area" },
 #endif
-# ifdef CONFIG_X86_ESPFIX64
-	{ ESPFIX_BASE_ADDR,	"ESPfix Area", 16 },
-# endif
-# ifdef CONFIG_EFI
-	{ EFI_VA_END,		"EFI Runtime Services" },
-# endif
-	{ __START_KERNEL_map,   "High Kernel Mapping" },
-	{ MODULES_VADDR,        "Modules" },
-	{ MODULES_END,          "End Modules" },
-#else
-	{ PAGE_OFFSET,          "Kernel Mapping" },
-	{ 0/* VMALLOC_START */, "vmalloc() Area" },
-	{ 0/*VMALLOC_END*/,     "vmalloc() End" },
-# ifdef CONFIG_HIGHMEM
-	{ 0/*PKMAP_BASE*/,      "Persistent kmap() Area" },
-# endif
-	{ 0/*FIXADDR_START*/,   "Fixmap Area" },
-#endif
-	{ -1, NULL }		/* End of list */
+	[CPU_ENTRY_AREA_NR]	= { 0UL,		"CPU entry area" },
+	[FIXADDR_START_NR]	= { 0UL,		"Fixmap area" },
+	[END_OF_SPACE_NR]	= { -1,			NULL }
 };
 
+#endif /* !CONFIG_X86_64 */
+
 /* Multipliers for offsets within the PTEs */
 #define PTE_LEVEL_MULT (PAGE_SIZE)
 #define PMD_LEVEL_MULT (PTRS_PER_PTE * PTE_LEVEL_MULT)
@@ -140,7 +160,7 @@ static void printk_prot(struct seq_file *m, pgprot_t prot, int level, bool dmsg)
 	static const char * const level_name[] =
 		{ "cr3", "pgd", "p4d", "pud", "pmd", "pte" };
 
-	if (!pgprot_val(prot)) {
+	if (!(pr & _PAGE_PRESENT)) {
 		/* Not present */
 		pt_dump_cont_printf(m, dmsg, "                              ");
 	} else {
@@ -525,8 +545,8 @@ static int __init pt_dump_init(void)
 	address_markers[PKMAP_BASE_NR].start_address = PKMAP_BASE;
 # endif
 	address_markers[FIXADDR_START_NR].start_address = FIXADDR_START;
+	address_markers[CPU_ENTRY_AREA_NR].start_address = CPU_ENTRY_AREA_BASE;
 #endif
-
 	return 0;
 }
 __initcall(pt_dump_init);