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

Pull x86 mm changes from Ingo Molnar:
 "PCID support, 5-level paging support, Secure Memory Encryption support

  The main changes in this cycle are support for three new, complex
  hardware features of x86 CPUs:

   - Add 5-level paging support, which is a new hardware feature on
     upcoming Intel CPUs allowing up to 128 PB of virtual address space
     and 4 PB of physical RAM space - a 512-fold increase over the old
     limits. (Supercomputers of the future forecasting hurricanes on an
     ever warming planet can certainly make good use of more RAM.)

     Many of the necessary changes went upstream in previous cycles,
     v4.14 is the first kernel that can enable 5-level paging.

     This feature is activated via CONFIG_X86_5LEVEL=y - disabled by
     default.

     (By Kirill A. Shutemov)

   - Add 'encrypted memory' support, which is a new hardware feature on
     upcoming AMD CPUs ('Secure Memory Encryption', SME) allowing system
     RAM to be encrypted and decrypted (mostly) transparently by the
     CPU, with a little help from the kernel to transition to/from
     encrypted RAM. Such RAM should be more secure against various
     attacks like RAM access via the memory bus and should make the
     radio signature of memory bus traffic harder to intercept (and
     decrypt) as well.

     This feature is activated via CONFIG_AMD_MEM_ENCRYPT=y - disabled
     by default.

     (By Tom Lendacky)

   - Enable PCID optimized TLB flushing on newer Intel CPUs: PCID is a
     hardware feature that attaches an address space tag to TLB entries
     and thus allows to skip TLB flushing in many cases, even if we
     switch mm's.

     (By Andy Lutomirski)

  All three of these features were in the works for a long time, and
  it's coincidence of the three independent development paths that they
  are all enabled in v4.14 at once"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (65 commits)
  x86/mm: Enable RCU based page table freeing (CONFIG_HAVE_RCU_TABLE_FREE=y)
  x86/mm: Use pr_cont() in dump_pagetable()
  x86/mm: Fix SME encryption stack ptr handling
  kvm/x86: Avoid clearing the C-bit in rsvd_bits()
  x86/CPU: Align CR3 defines
  x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages
  acpi, x86/mm: Remove encryption mask from ACPI page protection type
  x86/mm, kexec: Fix memory corruption with SME on successive kexecs
  x86/mm/pkeys: Fix typo in Documentation/x86/protection-keys.txt
  x86/mm/dump_pagetables: Speed up page tables dump for CONFIG_KASAN=y
  x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID
  x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y
  x86/mm: Allow userspace have mappings above 47-bit
  x86/mm: Prepare to expose larger address space to userspace
  x86/mpx: Do not allow MPX if we have mappings above 47-bit
  x86/mm: Rename tasksize_32bit/64bit to task_size_32bit/64bit()
  x86/xen: Redefine XEN_ELFNOTE_INIT_P2M using PUD_SIZE * PTRS_PER_PUD
  x86/mm/dump_pagetables: Fix printout of p4d level
  x86/mm/dump_pagetables: Generalize address normalization
  x86/boot: Fix memremap() related build failure
  ...

1 files changed, 49 insertions, 0 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index cce15191e9e9..b4b27ab016f6 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -169,6 +169,7 @@ config X86
 	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
 	select HAVE_PERF_REGS
 	select HAVE_PERF_USER_STACK_DUMP
+	select HAVE_RCU_TABLE_FREE
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_RELIABLE_STACKTRACE		if X86_64 && FRAME_POINTER_UNWINDER && STACK_VALIDATION
 	select HAVE_STACK_VALIDATION		if X86_64
@@ -329,6 +330,7 @@ config FIX_EARLYCON_MEM
 
 config PGTABLE_LEVELS
 	int
+	default 5 if X86_5LEVEL
 	default 4 if X86_64
 	default 3 if X86_PAE
 	default 2
@@ -1399,6 +1401,24 @@ config X86_PAE
 	  has the cost of more pagetable lookup overhead, and also
 	  consumes more pagetable space per process.
 
+config X86_5LEVEL
+	bool "Enable 5-level page tables support"
+	depends on X86_64
+	---help---
+	  5-level paging enables access to larger address space:
+	  upto 128 PiB of virtual address space and 4 PiB of
+	  physical address space.
+
+	  It will be supported by future Intel CPUs.
+
+	  Note: a kernel with this option enabled can only be booted
+	  on machines that support the feature.
+
+	  See Documentation/x86/x86_64/5level-paging.txt for more
+	  information.
+
+	  Say N if unsure.
+
 config ARCH_PHYS_ADDR_T_64BIT
 	def_bool y
 	depends on X86_64 || X86_PAE
@@ -1416,6 +1436,35 @@ config X86_DIRECT_GBPAGES
 	  supports them), so don't confuse the user by printing
 	  that we have them enabled.
 
+config ARCH_HAS_MEM_ENCRYPT
+	def_bool y
+
+config AMD_MEM_ENCRYPT
+	bool "AMD Secure Memory Encryption (SME) support"
+	depends on X86_64 && CPU_SUP_AMD
+	---help---
+	  Say yes to enable support for the encryption of system memory.
+	  This requires an AMD processor that supports Secure Memory
+	  Encryption (SME).
+
+config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
+	bool "Activate AMD Secure Memory Encryption (SME) by default"
+	default y
+	depends on AMD_MEM_ENCRYPT
+	---help---
+	  Say yes to have system memory encrypted by default if running on
+	  an AMD processor that supports Secure Memory Encryption (SME).
+
+	  If set to Y, then the encryption of system memory can be
+	  deactivated with the mem_encrypt=off command line option.
+
+	  If set to N, then the encryption of system memory can be
+	  activated with the mem_encrypt=on command line option.
+
+config ARCH_USE_MEMREMAP_PROT
+	def_bool y
+	depends on AMD_MEM_ENCRYPT
+
 # Common NUMA Features
 config NUMA
 	bool "Numa Memory Allocation and Scheduler Support"