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-rw-r--r--arch/x86/boot/compressed/head_64.S27
-rw-r--r--arch/x86/boot/compressed/pgtable.h2
2 files changed, 14 insertions, 15 deletions
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 381ca6bf62d3..c28f7ef80ad2 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -447,9 +447,9 @@ SYM_CODE_START(startup_64)
movq %r15, %rdi
call paging_prepare
- /* Save the trampoline address in RCX */
- movq %rax, %rcx
-
+ /* Pass the trampoline address and boolean flag as args #1 and #2 */
+ movq %rax, %rdi
+ movq %rdx, %rsi
leaq TRAMPOLINE_32BIT_CODE_OFFSET(%rax), %rax
call *%rax
@@ -549,11 +549,14 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
SYM_FUNC_END(.Lrelocated)
/*
- * This is the 32-bit trampoline that will be copied over to low memory.
+ * This is the 32-bit trampoline that will be copied over to low memory. It
+ * will be called using the ordinary 64-bit calling convention from code
+ * running in 64-bit mode.
*
* Return address is at the top of the stack (might be above 4G).
- * ECX contains the base address of the trampoline memory.
- * Non zero RDX means trampoline needs to enable 5-level paging.
+ * The first argument (EDI) contains the 32-bit addressable base of the
+ * trampoline memory. A non-zero second argument (ESI) means that the
+ * trampoline needs to enable 5-level paging.
*/
SYM_CODE_START(trampoline_32bit_src)
/*
@@ -600,7 +603,7 @@ SYM_CODE_START(trampoline_32bit_src)
movl %eax, %cr0
/* Check what paging mode we want to be in after the trampoline */
- testl %edx, %edx
+ testl %esi, %esi
jz 1f
/* We want 5-level paging: don't touch CR3 if it already points to 5-level page tables */
@@ -615,21 +618,17 @@ SYM_CODE_START(trampoline_32bit_src)
jz 3f
2:
/* Point CR3 to the trampoline's new top level page table */
- leal TRAMPOLINE_32BIT_PGTABLE_OFFSET(%ecx), %eax
+ leal TRAMPOLINE_32BIT_PGTABLE_OFFSET(%edi), %eax
movl %eax, %cr3
3:
/* Set EFER.LME=1 as a precaution in case hypervsior pulls the rug */
- pushl %ecx
- pushl %edx
movl $MSR_EFER, %ecx
rdmsr
btsl $_EFER_LME, %eax
/* Avoid writing EFER if no change was made (for TDX guest) */
jc 1f
wrmsr
-1: popl %edx
- popl %ecx
-
+1:
#ifdef CONFIG_X86_MCE
/*
* Preserve CR4.MCE if the kernel will enable #MC support.
@@ -646,7 +645,7 @@ SYM_CODE_START(trampoline_32bit_src)
/* Enable PAE and LA57 (if required) paging modes */
orl $X86_CR4_PAE, %eax
- testl %edx, %edx
+ testl %esi, %esi
jz 1f
orl $X86_CR4_LA57, %eax
1:
diff --git a/arch/x86/boot/compressed/pgtable.h b/arch/x86/boot/compressed/pgtable.h
index 91dbb99203fb..4e8cef135226 100644
--- a/arch/x86/boot/compressed/pgtable.h
+++ b/arch/x86/boot/compressed/pgtable.h
@@ -14,7 +14,7 @@
extern unsigned long *trampoline_32bit;
-extern void trampoline_32bit_src(void *return_ptr);
+extern void trampoline_32bit_src(void *trampoline, bool enable_5lvl);
#endif /* __ASSEMBLER__ */
#endif /* BOOT_COMPRESSED_PAGETABLE_H */