This is a note to let you know that I've just added the patch titled
x86/boot/compressed: Move efi32_entry out of head_64.S
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-boot-compressed-move-efi32_entry-out-of-head_64.s.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 73a6dec80e2acedaef3ca603d4b5799049f6e9f8 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@xxxxxxxxxx>
Date: Tue, 22 Nov 2022 17:10:05 +0100
Subject: x86/boot/compressed: Move efi32_entry out of head_64.S
From: Ard Biesheuvel <ardb@xxxxxxxxxx>
commit 73a6dec80e2acedaef3ca603d4b5799049f6e9f8 upstream.
Move the efi32_entry() routine out of head_64.S and into efi-mixed.S,
which reduces clutter in the complicated startup routines. It also
permits linkage of some symbols used by code to be made local.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lore.kernel.org/r/20221122161017.2426828-6-ardb@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/boot/compressed/efi_mixed.S | 57 ++++++++++++++++++++++++++++-------
arch/x86/boot/compressed/head_64.S | 45 ---------------------------
2 files changed, 47 insertions(+), 55 deletions(-)
--- a/arch/x86/boot/compressed/efi_mixed.S
+++ b/arch/x86/boot/compressed/efi_mixed.S
@@ -105,7 +105,7 @@ SYM_FUNC_START(__efi64_thunk)
/*
* 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.
+ * pointers were saved by the efi32_entry() routine below.
*
* Pass the saved DS selector to the 32-bit code, and use far return to
* restore the saved CS selector.
@@ -217,22 +217,59 @@ SYM_FUNC_START_LOCAL(efi_enter32)
lret
SYM_FUNC_END(efi_enter32)
+/*
+ * This is the common EFI stub entry point for mixed mode.
+ *
+ * Arguments: %ecx image handle
+ * %edx EFI system table pointer
+ * %esi struct bootparams pointer (or NULL when not using
+ * the EFI handover protocol)
+ *
+ * Since this is the point of no return for ordinary execution, no registers
+ * are considered live except for the function parameters. [Note that the EFI
+ * stub may still exit and return to the firmware using the Exit() EFI boot
+ * service.]
+ */
+SYM_FUNC_START(efi32_entry)
+ call 1f
+1: pop %ebx
+
+ /* Save firmware GDTR and code/data selectors */
+ sgdtl (efi32_boot_gdt - 1b)(%ebx)
+ movw %cs, (efi32_boot_cs - 1b)(%ebx)
+ movw %ds, (efi32_boot_ds - 1b)(%ebx)
+
+ /* Store firmware IDT descriptor */
+ sidtl (efi32_boot_idt - 1b)(%ebx)
+
+ /* Store boot arguments */
+ leal (efi32_boot_args - 1b)(%ebx), %ebx
+ movl %ecx, 0(%ebx)
+ movl %edx, 4(%ebx)
+ movl %esi, 8(%ebx)
+ movb $0x0, 12(%ebx) // efi_is64
+
+ /* Disable paging */
+ movl %cr0, %eax
+ btrl $X86_CR0_PG_BIT, %eax
+ movl %eax, %cr0
+
+ jmp startup_32
+SYM_FUNC_END(efi32_entry)
+
.data
.balign 8
-SYM_DATA_START(efi32_boot_gdt)
+SYM_DATA_START_LOCAL(efi32_boot_gdt)
.word 0
.quad 0
SYM_DATA_END(efi32_boot_gdt)
-SYM_DATA_START(efi32_boot_idt)
+SYM_DATA_START_LOCAL(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)
-
-SYM_DATA_START(efi32_boot_ds)
- .word 0
-SYM_DATA_END(efi32_boot_ds)
+SYM_DATA_LOCAL(efi32_boot_cs, .word 0)
+SYM_DATA_LOCAL(efi32_boot_ds, .word 0)
+SYM_DATA_LOCAL(efi32_boot_args, .long 0, 0, 0)
+SYM_DATA(efi_is64, .byte 1)
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -289,48 +289,6 @@ SYM_FUNC_START(efi32_stub_entry)
popl %esi
jmp efi32_entry
SYM_FUNC_END(efi32_stub_entry)
-
- .text
-/*
- * This is the common EFI stub entry point for mixed mode.
- *
- * Arguments: %ecx image handle
- * %edx EFI system table pointer
- * %esi struct bootparams pointer (or NULL when not using
- * the EFI handover protocol)
- *
- * Since this is the point of no return for ordinary execution, no registers
- * are considered live except for the function parameters. [Note that the EFI
- * stub may still exit and return to the firmware using the Exit() EFI boot
- * service.]
- */
-SYM_FUNC_START_LOCAL(efi32_entry)
- call 1f
-1: pop %ebx
-
- /* Save firmware GDTR and code/data selectors */
- sgdtl (efi32_boot_gdt - 1b)(%ebx)
- movw %cs, (efi32_boot_cs - 1b)(%ebx)
- movw %ds, (efi32_boot_ds - 1b)(%ebx)
-
- /* Store firmware IDT descriptor */
- sidtl (efi32_boot_idt - 1b)(%ebx)
-
- /* Store boot arguments */
- leal (efi32_boot_args - 1b)(%ebx), %ebx
- movl %ecx, 0(%ebx)
- movl %edx, 4(%ebx)
- movl %esi, 8(%ebx)
- movb $0x0, 12(%ebx) // efi_is64
-
- /* Disable paging */
- movl %cr0, %eax
- btrl $X86_CR0_PG_BIT, %eax
- movl %eax, %cr0
-
- jmp startup_32
-SYM_FUNC_END(efi32_entry)
- __HEAD
#endif
.code64
@@ -779,9 +737,6 @@ SYM_DATA_END_LABEL(boot32_idt, SYM_L_GLO
SYM_DATA(image_offset, .long 0)
#endif
#ifdef CONFIG_EFI_MIXED
-SYM_DATA(efi32_boot_args, .long 0, 0, 0)
-SYM_DATA(efi_is64, .byte 1)
-
#define ST32_boottime 60 // offsetof(efi_system_table_32_t, boottime)
#define BS32_handle_protocol 88 // offsetof(efi_boot_services_32_t, handle_protocol)
#define LI32_image_base 32 // offsetof(efi_loaded_image_32_t, image_base)
Patches currently in stable-queue which might be from ardb@xxxxxxxxxx are
queue-6.1/x86-boot-compressed-avoid-touching-ecx-in-startup32_set_idt_entry.patch
queue-6.1/x86-boot-compressed-only-build-mem_encrypt.s-if-amd_mem_encrypt-y.patch
queue-6.1/efi-capsule-loader-fix-incorrect-allocation-size.patch
queue-6.1/x86-decompressor-move-global-symbol-references-to-c-code.patch
queue-6.1/x86-boot-compressed-move-startup32_load_idt-into-.text-section.patch
queue-6.1/x86-decompressor-only-call-the-trampoline-when-changing-paging-levels.patch
queue-6.1/x86-boot-compressed-rename-efi_thunk_64.s-to-efi-mixed.s.patch
queue-6.1/x86-decompressor-merge-trampoline-cleanup-with-switching-code.patch
queue-6.1/x86-boot-compressed-move-efi32_pe_entry-out-of-head_64.s.patch
queue-6.1/efi-verify-that-variable-services-are-supported.patch
queue-6.1/x86-decompressor-call-trampoline-directly-from-c-code.patch
queue-6.1/x86-boot-compressed-pull-global-variable-reference-into-startup32_load_idt.patch
queue-6.1/x86-boot-compressed-simplify-idt-gdt-preserve-restore-in-the-efi-thunk.patch
queue-6.1/x86-decompressor-assign-paging-related-global-variables-earlier.patch
queue-6.1/x86-boot-compressed-move-32-bit-entrypoint-code-into-.text-section.patch
queue-6.1/x86-boot-compressed-move-efi32_pe_entry-into-.text-section.patch
queue-6.1/x86-decompressor-avoid-the-need-for-a-stack-in-the-32-bit-trampoline.patch
queue-6.1/x86-boot-compressed-move-startup32_check_sev_cbit-out-of-head_64.s.patch
queue-6.1/x86-boot-compressed-efi-merge-multiple-definitions-of-image_offset-into-one.patch
queue-6.1/x86-boot-compressed-move-startup32_load_idt-out-of-head_64.s.patch
queue-6.1/decompress-use-8-byte-alignment.patch
queue-6.1/x86-boot-compressed-move-efi32_entry-out-of-head_64.s.patch
queue-6.1/efi-libstub-use-efi_loader_code-region-when-moving-the-kernel-in-memory.patch
queue-6.1/crypto-arm64-neonbs-fix-out-of-bounds-access-on-short-input.patch
queue-6.1/x86-boot-compressed-move-bootargs-parsing-out-of-32-bit-startup-code.patch
queue-6.1/efivarfs-request-at-most-512-bytes-for-variable-names.patch
queue-6.1/x86-boot-compressed-adhere-to-calling-convention-in-get_sev_encryption_bit.patch
queue-6.1/x86-boot-compressed-move-startup32_check_sev_cbit-into-.text.patch
queue-6.1/x86-decompressor-store-boot_params-pointer-in-callee-save-register.patch
queue-6.1/x86-efistub-branch-straight-to-kernel-entry-point-from-c-code.patch
queue-6.1/x86-decompressor-call-trampoline-as-a-normal-function.patch
queue-6.1/x86-decompressor-pass-pgtable-address-to-trampoline-directly.patch
queue-6.1/x86-decompressor-use-standard-calling-convention-for-trampoline.patch
queue-6.1/x86-efi-make-the-deprecated-efi-handover-protocol-optional.patch
