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Diffstat (limited to 'arch/x86/kernel/head_64.S')
-rw-r--r--arch/x86/kernel/head_64.S37
1 files changed, 34 insertions, 3 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index b8e3019547a5..7bac9a4bdf7c 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -65,10 +65,39 @@ SYM_CODE_START_NOALIGN(startup_64)
leaq (__end_init_task - FRAME_SIZE)(%rip), %rsp
leaq _text(%rip), %rdi
+
+ /*
+ * initial_gs points to initial fixed_percpu_data struct with storage for
+ * the stack protector canary. Global pointer fixups are needed at this
+ * stage, so apply them as is done in fixup_pointer(), and initialize %gs
+ * such that the canary can be accessed at %gs:40 for subsequent C calls.
+ */
+ movl $MSR_GS_BASE, %ecx
+ movq initial_gs(%rip), %rax
+ movq $_text, %rdx
+ subq %rdx, %rax
+ addq %rdi, %rax
+ movq %rax, %rdx
+ shrq $32, %rdx
+ wrmsr
+
pushq %rsi
call startup_64_setup_env
popq %rsi
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ /*
+ * Activate SEV/SME memory encryption if supported/enabled. This needs to
+ * be done now, since this also includes setup of the SEV-SNP CPUID table,
+ * which needs to be done before any CPUID instructions are executed in
+ * subsequent code.
+ */
+ movq %rsi, %rdi
+ pushq %rsi
+ call sme_enable
+ popq %rsi
+#endif
+
/* Now switch to __KERNEL_CS so IRET works reliably */
pushq $__KERNEL_CS
leaq .Lon_kernel_cs(%rip), %rax
@@ -134,9 +163,11 @@ SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL)
* 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
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ movq sme_me_mask, %rax
+#else
+ xorq %rax, %rax
+#endif
/* Form the CR3 value being sure to include the CR3 modifier */
addq $(init_top_pgt - __START_KERNEL_map), %rax