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authorTom Lendacky <thomas.lendacky@amd.com>2017-07-17 16:10:05 -0500
committerIngo Molnar <mingo@kernel.org>2017-07-18 11:37:59 +0200
commit5868f3651fa0dff96a57f94d49247d3ef320ebe2 (patch)
tree11b9fdc343371d2d40d476ebddde2d0532c78ea9 /arch/x86/kernel/head_64.S
parent33c2b803edd13487518a2c7d5002d84d7e9c878f (diff)
x86/mm: Add support to enable SME in early boot processing
Add support to the early boot code to use Secure Memory Encryption (SME). Since the kernel has been loaded into memory in a decrypted state, encrypt the kernel in place and update the early pagetables with the memory encryption mask so that new pagetable entries will use memory encryption. The routines to set the encryption mask and perform the encryption are stub routines for now with functionality to be added in a later patch. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Dave Young <dyoung@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Toshimitsu Kani <toshi.kani@hpe.com> Cc: kasan-dev@googlegroups.com Cc: kvm@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-efi@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/e52ad781f085224bf835b3caff9aa3aee6febccb.1500319216.git.thomas.lendacky@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/head_64.S')
-rw-r--r--arch/x86/kernel/head_64.S20
1 files changed, 18 insertions, 2 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 6225550883df..ec5d5e90c8f1 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -73,12 +73,19 @@ startup_64:
/* Sanitize CPU configuration */
call verify_cpu
+ /*
+ * Perform pagetable fixups. Additionally, if SME is active, encrypt
+ * the kernel and retrieve the modifier (SME encryption mask if SME
+ * is active) to be added to the initial pgdir entry that will be
+ * programmed into CR3.
+ */
leaq _text(%rip), %rdi
pushq %rsi
call __startup_64
popq %rsi
- movq $(early_top_pgt - __START_KERNEL_map), %rax
+ /* Form the CR3 value being sure to include the CR3 modifier */
+ addq $(early_top_pgt - __START_KERNEL_map), %rax
jmp 1f
ENTRY(secondary_startup_64)
/*
@@ -98,7 +105,16 @@ ENTRY(secondary_startup_64)
/* Sanitize CPU configuration */
call verify_cpu
- movq $(init_top_pgt - __START_KERNEL_map), %rax
+ /*
+ * Retrieve the modifier (SME encryption mask if SME is active) to be
+ * added to the initial pgdir entry that will be programmed into CR3.
+ */
+ pushq %rsi
+ call __startup_secondary_64
+ popq %rsi
+
+ /* Form the CR3 value being sure to include the CR3 modifier */
+ addq $(init_top_pgt - __START_KERNEL_map), %rax
1:
/* Enable PAE mode, PGE and LA57 */