This is a note to let you know that I've just added the patch titled
x86/boot/compressed: Move startup32_load_idt() into .text section
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-startup32_load_idt-into-.text-section.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 c6355995ba471d7ad574174e593192ce805c7e1a Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@xxxxxxxxxx>
Date: Tue, 22 Nov 2022 17:10:11 +0100
Subject: x86/boot/compressed: Move startup32_load_idt() into .text section
From: Ard Biesheuvel <ardb@xxxxxxxxxx>
commit c6355995ba471d7ad574174e593192ce805c7e1a upstream.
Convert startup32_load_idt() into an ordinary function and move it into
the .text section. This involves turning the rva() immediates into ones
derived from a local label, and preserving/restoring the %ebp and %ebx
as per the calling convention.
Also move the #ifdef to the only existing call site. This makes it clear
that the function call does nothing if support for memory encryption is
not compiled in.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lore.kernel.org/r/20221122161017.2426828-12-ardb@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/boot/compressed/head_64.S | 31 ++++++++++++++++++++-----------
1 file changed, 20 insertions(+), 11 deletions(-)
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -118,7 +118,9 @@ SYM_FUNC_START(startup_32)
1:
/* Setup Exception handling for SEV-ES */
+#ifdef CONFIG_AMD_MEM_ENCRYPT
call startup32_load_idt
+#endif
/* Make sure cpu supports long mode. */
call verify_cpu
@@ -732,10 +734,8 @@ SYM_DATA_START(boot32_idt)
.quad 0
.endr
SYM_DATA_END_LABEL(boot32_idt, SYM_L_GLOBAL, boot32_idt_end)
-#endif
-#ifdef CONFIG_AMD_MEM_ENCRYPT
- __HEAD
+ .text
.code32
/*
* Write an IDT entry into boot32_idt
@@ -768,24 +768,32 @@ SYM_FUNC_START_LOCAL(startup32_set_idt_e
RET
SYM_FUNC_END(startup32_set_idt_entry)
-#endif
SYM_FUNC_START(startup32_load_idt)
-#ifdef CONFIG_AMD_MEM_ENCRYPT
- leal rva(boot32_idt)(%ebp), %ecx
+ push %ebp
+ push %ebx
+
+ call 1f
+1: pop %ebp
+
+ leal (boot32_idt - 1b)(%ebp), %ebx
/* #VC handler */
- leal rva(startup32_vc_handler)(%ebp), %eax
+ leal (startup32_vc_handler - 1b)(%ebp), %eax
movl $X86_TRAP_VC, %edx
+ movl %ebx, %ecx
call startup32_set_idt_entry
/* Load IDT */
- leal rva(boot32_idt)(%ebp), %eax
- movl %eax, rva(boot32_idt_desc+2)(%ebp)
- lidt rva(boot32_idt_desc)(%ebp)
-#endif
+ leal (boot32_idt_desc - 1b)(%ebp), %ecx
+ movl %ebx, 2(%ecx)
+ lidt (%ecx)
+
+ pop %ebx
+ pop %ebp
RET
SYM_FUNC_END(startup32_load_idt)
+#endif
/*
* Check for the correct C-bit position when the startup_32 boot-path is used.
@@ -804,6 +812,7 @@ SYM_FUNC_END(startup32_load_idt)
* succeed. An incorrect C-bit position will map all memory unencrypted, so that
* the compare will use the encrypted random data and fail.
*/
+ __HEAD
SYM_FUNC_START(startup32_check_sev_cbit)
#ifdef CONFIG_AMD_MEM_ENCRYPT
pushl %eax
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
