Merge tag 'dt-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

[linux-2.6-microblaze.git] / arch / x86 / boot / compressed / efi_thunk_64.S

diff --git a/arch/x86/boot/compressed/efi_thunk_64.S b/arch/x86/boot/compressed/efi_thunk_64.S
index 95a223b..8bb92e9 100644 (file)
--- a/arch/x86/boot/compressed/efi_thunk_64.S
+++ b/arch/x86/boot/compressed/efi_thunk_64.S
@@ -5,9 +5,8 @@
  * Early support for invoking 32-bit EFI services from a 64-bit kernel.
  *
  * Because this thunking occurs before ExitBootServices() we have to
- * restore the firmware's 32-bit GDT before we make EFI service calls,
- * since the firmware's 32-bit IDT is still currently installed and it
- * needs to be able to service interrupts.
+ * restore the firmware's 32-bit GDT and IDT before we make EFI service
+ * calls.
  *
  * On the plus side, we don't have to worry about mangling 64-bit
  * addresses into 32-bits because we're executing with an identity
@@ -39,7 +38,7 @@ SYM_FUNC_START(__efi64_thunk)
        /*
         * Convert x86-64 ABI params to i386 ABI
         */
-       subq    $32, %rsp
+       subq    $64, %rsp
        movl    %esi, 0x0(%rsp)
        movl    %edx, 0x4(%rsp)
        movl    %ecx, 0x8(%rsp)
@@ -49,14 +48,19 @@ SYM_FUNC_START(__efi64_thunk)
        leaq    0x14(%rsp), %rbx
        sgdt    (%rbx)
 
+       addq    $16, %rbx
+       sidt    (%rbx)
+
        /*
-        * Switch to gdt with 32-bit segments. This is the firmware GDT
-        * that was installed when the kernel started executing. This
-        * pointer was saved at the EFI stub entry point in head_64.S.
+        * Switch to IDT and GDT with 32-bit segments. This is the firmware GDT
+        * and IDT that was installed when the kernel started executing. The
+        * pointers were saved at the EFI stub entry point in head_64.S.
         *
         * Pass the saved DS selector to the 32-bit code, and use far return to
         * restore the saved CS selector.
         */
+       leaq    efi32_boot_idt(%rip), %rax
+       lidt    (%rax)
        leaq    efi32_boot_gdt(%rip), %rax
        lgdt    (%rax)
 
@@ -67,7 +71,7 @@ SYM_FUNC_START(__efi64_thunk)
        pushq   %rax
        lretq
 
-1:     addq    $32, %rsp
+1:     addq    $64, %rsp
        movq    %rdi, %rax
 
        pop     %rbx
@@ -128,10 +132,13 @@ SYM_FUNC_START_LOCAL(efi_enter32)
 
        /*
         * Some firmware will return with interrupts enabled. Be sure to
-        * disable them before we switch GDTs.
+        * disable them before we switch GDTs and IDTs.
         */
        cli
 
+       lidtl   (%ebx)
+       subl    $16, %ebx
+
        lgdtl   (%ebx)
 
        movl    %cr4, %eax
@@ -166,6 +173,11 @@ SYM_DATA_START(efi32_boot_gdt)
        .quad   0
 SYM_DATA_END(efi32_boot_gdt)
 
+SYM_DATA_START(efi32_boot_idt)
+       .word   0
+       .quad   0
+SYM_DATA_END(efi32_boot_idt)
+
 SYM_DATA_START(efi32_boot_cs)
        .word   0
 SYM_DATA_END(efi32_boot_cs)