linux-kernel - [PATCH v3 04/17] x86/compressed: efi-mixed: move efi32_pe

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Date:   Tue, 22 Nov 2022 17:10:04 +0100
From:   Ard Biesheuvel <ardb@...nel.org>
To:     linux-efi@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org, Ard Biesheuvel <ardb@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Michael Roth <michael.roth@....com>
Subject: [PATCH v3 04/17] x86/compressed: efi-mixed: move efi32_pe_entry into .text section

Move efi32_pe_entry() into the .text section, so that it can be moved
out of head_64.S and into a separate compilation unit in a subsequent
patch.

Signed-off-by: Ard Biesheuvel <ardb@...nel.org>
---
 arch/x86/boot/compressed/head_64.S | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index b9dbc8127038c315..8192ab1c308567ce 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -778,7 +778,7 @@ SYM_DATA(efi_is64, .byte 1)
 #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)
 
-	__HEAD
+	.text
 	.code32
 SYM_FUNC_START(efi32_pe_entry)
 /*
@@ -800,12 +800,11 @@ SYM_FUNC_START(efi32_pe_entry)
 
 	call	1f
 1:	pop	%ebx
-	subl	$ rva(1b), %ebx
 
 	/* Get the loaded image protocol pointer from the image handle */
 	leal	-4(%ebp), %eax
 	pushl	%eax				// &loaded_image
-	leal	rva(loaded_image_proto)(%ebx), %eax
+	leal	(loaded_image_proto - 1b)(%ebx), %eax
 	pushl	%eax				// pass the GUID address
 	pushl	8(%ebp)				// pass the image handle
 
@@ -834,13 +833,13 @@ SYM_FUNC_START(efi32_pe_entry)
 	movl	12(%ebp), %edx			// sys_table
 	movl	-4(%ebp), %esi			// loaded_image
 	movl	LI32_image_base(%esi), %esi	// loaded_image->image_base
-	movl	%ebx, %ebp			// startup_32 for efi32_pe_stub_entry
+	leal	(startup_32 - 1b)(%ebx), %ebp	// runtime address of startup_32
 	/*
 	 * We need to set the image_offset variable here since startup_32() will
 	 * use it before we get to the 64-bit efi_pe_entry() in C code.
 	 */
-	subl	%esi, %ebx
-	movl	%ebx, rva(image_offset)(%ebp)	// save image_offset
+	subl	%esi, %ebp			// calculate image_offset
+	movl	%ebp, (image_offset - 1b)(%ebx)	// save image_offset
 	xorl	%esi, %esi
 	jmp	efi32_entry			// pass %ecx, %edx, %esi
 						// no other registers remain live
-- 
2.35.1