[tip:x86/mm] x86/mm: Add SME support for read_cr3_pa()

[tip-bot for Tom Lendacky]

Commit-ID:  eef9c4abe77f55b1600f59d8ac5f1d953e2f5384
Gitweb:     http://git.kernel.org/tip/eef9c4abe77f55b1600f59d8ac5f1d953e2f5384
Author:     Tom Lendacky <thomas.lendacky@xxxxxxx>
AuthorDate: Mon, 17 Jul 2017 16:10:08 -0500
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 18 Jul 2017 11:38:00 +0200

x86/mm: Add SME support for read_cr3_pa()

The CR3 register entry can contain the SME encryption mask that indicates
the PGD is encrypted.  The encryption mask should not be used when
creating a virtual address from the CR3 register, so remove the SME
encryption mask in the read_cr3_pa() function.

During early boot SME will need to use a native version of read_cr3_pa(),
so create native_read_cr3_pa().

Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Borislav Petkov <bp@xxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Brijesh Singh <brijesh.singh@xxxxxxx>
Cc: Dave Young <dyoung@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Cc: Larry Woodman <lwoodman@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Toshimitsu Kani <toshi.kani@xxxxxxx>
Cc: kasan-dev@xxxxxxxxxxxxxxxx
Cc: kvm@xxxxxxxxxxxxxxx
Cc: linux-arch@xxxxxxxxxxxxxxx
Cc: linux-doc@xxxxxxxxxxxxxxx
Cc: linux-efi@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Link: http://lkml.kernel.org/r/767b085c384a46f67f451f8589903a462c7ff68a.1500319216.git.thomas.lendacky@xxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 arch/x86/include/asm/processor-flags.h | 5 +++--
 arch/x86/include/asm/processor.h       | 5 +++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/processor-flags.h b/arch/x86/include/asm/processor-flags.h
index 79aa2f9..f5d3e50 100644
--- a/arch/x86/include/asm/processor-flags.h
+++ b/arch/x86/include/asm/processor-flags.h
@@ -2,6 +2,7 @@
 #define _ASM_X86_PROCESSOR_FLAGS_H
 
 #include <uapi/asm/processor-flags.h>
+#include <linux/mem_encrypt.h>
 
 #ifdef CONFIG_VM86
 #define X86_VM_MASK	X86_EFLAGS_VM
@@ -32,8 +33,8 @@
  * CR3_ADDR_MASK is the mask used by read_cr3_pa().
  */
 #ifdef CONFIG_X86_64
-/* Mask off the address space ID bits. */
-#define CR3_ADDR_MASK 0x7FFFFFFFFFFFF000ull
+/* Mask off the address space ID and SME encryption bits. */
+#define CR3_ADDR_MASK __sme_clr(0x7FFFFFFFFFFFF000ull)
 #define CR3_PCID_MASK 0xFFFull
 #else
 /*
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index a68f70c..973709d 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -240,6 +240,11 @@ static inline unsigned long read_cr3_pa(void)
 	return __read_cr3() & CR3_ADDR_MASK;
 }
 
+static inline unsigned long native_read_cr3_pa(void)
+{
+	return __native_read_cr3() & CR3_ADDR_MASK;
+}
+
 static inline void load_cr3(pgd_t *pgdir)
 {
 	write_cr3(__sme_pa(pgdir));