From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1040875AbdDUOYG (ORCPT ); Fri, 21 Apr 2017 10:24:06 -0400 Received: from mx2.suse.de ([195.135.220.15]:56022 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1035635AbdDUONH (ORCPT ); Fri, 21 Apr 2017 10:13:07 -0400 From: Jiri Slaby To: mingo@redhat.com Cc: tglx@linutronix.de, hpa@zytor.com, x86@kernel.org, jpoimboe@redhat.com, linux-kernel@vger.kernel.org, Jiri Slaby , David Woodhouse , Matt Fleming Subject: [PATCH v3 02/29] x86_32: boot, extract efi_pe_entry from startup_32 Date: Fri, 21 Apr 2017 16:12:38 +0200 Message-Id: <20170421141305.25180-2-jslaby@suse.cz> X-Mailer: git-send-email 2.12.2 In-Reply-To: <20170421141305.25180-1-jslaby@suse.cz> References: <20170421141305.25180-1-jslaby@suse.cz> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org efi_pe_entry body is somehow squashed into startup_32. In the old days, we forced startup_32 to start at offset 0x00 and efi_pe_entry to start at 0x10. But this requirement was removed in 99f857db8857 ("x86, build: Dynamically find entry points in compressed startup code") long time ago. The way it is now makes the code less readable and illogical. And given we can now safely extract the inlined efi_pe_entry body from startup_32 into a separate function, we do so and we separate it to two functions as they are marked already: efi_pe_entry + efi32_stub_entry. We also annotate the functions appropriatelly by ENTRY+ENDPROC. ABI offset is preserved: 0000 128 FUNC GLOBAL DEFAULT 6 startup_32 0080 60 FUNC GLOBAL DEFAULT 6 efi_pe_entry 00bc 68 FUNC GLOBAL DEFAULT 6 efi32_stub_entry On the top-level, it looked like: ENTRY(startup_32) #ifdef CONFIG_EFI_STUB ; start of inlined jmp preferred_addr ENTRY(efi_pe_entry) ... ; a lot of assembly (efi_pe_entry) ENTRY(efi32_stub_entry) ... ; a lot of assembly (efi32_stub_entry) leal preferred_addr(%eax), %eax jmp *%eax preferred_addr: #endif ; end of inlined ... ; a lot of assembly (startup_32) ENDPROC(startup_32) And it is converted into: ENTRY(startup_32) ... ; a lot of assembly (startup_32) ENDPROC(startup_32) #ifdef CONFIG_EFI_STUB ENTRY(efi_pe_entry) ... ; a lot of assembly (efi_pe_entry) ENDPROC(efi_pe_entry) ENTRY(efi32_stub_entry) ... ; a lot of assembly (efi32_stub_entry) leal startup_32(%eax), %eax jmp *%eax ENDPROC(efi32_stub_entry) #endif Signed-off-by: Jiri Slaby Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Cc: David Woodhouse Cc: Matt Fleming --- arch/x86/boot/compressed/head_32.S | 129 ++++++++++++++++++------------------- 1 file changed, 64 insertions(+), 65 deletions(-) diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S index d85b9625e836..11c68cf53d4e 100644 --- a/arch/x86/boot/compressed/head_32.S +++ b/arch/x86/boot/compressed/head_32.S @@ -61,71 +61,6 @@ __HEAD ENTRY(startup_32) -#ifdef CONFIG_EFI_STUB - jmp preferred_addr - - /* - * We don't need the return address, so set up the stack so - * efi_main() can find its arguments. - */ -ENTRY(efi_pe_entry) - add $0x4, %esp - - call 1f -1: popl %esi - subl $1b, %esi - - popl %ecx - movl %ecx, efi32_config(%esi) /* Handle */ - popl %ecx - movl %ecx, efi32_config+8(%esi) /* EFI System table pointer */ - - /* Relocate efi_config->call() */ - leal efi32_config(%esi), %eax - add %esi, 40(%eax) - pushl %eax - - call make_boot_params - cmpl $0, %eax - je fail - movl %esi, BP_code32_start(%eax) - popl %ecx - pushl %eax - pushl %ecx - jmp 2f /* Skip efi_config initialization */ - -ENTRY(efi32_stub_entry) - add $0x4, %esp - popl %ecx - popl %edx - - call 1f -1: popl %esi - subl $1b, %esi - - movl %ecx, efi32_config(%esi) /* Handle */ - movl %edx, efi32_config+8(%esi) /* EFI System table pointer */ - - /* Relocate efi_config->call() */ - leal efi32_config(%esi), %eax - add %esi, 40(%eax) - pushl %eax -2: - call efi_main - cmpl $0, %eax - movl %eax, %esi - jne 2f -fail: - /* EFI init failed, so hang. */ - hlt - jmp fail -2: - movl BP_code32_start(%esi), %eax - leal preferred_addr(%eax), %eax - jmp *%eax - -preferred_addr: -#endif cld /* * Test KEEP_SEGMENTS flag to see if the bootloader is asking @@ -208,6 +143,70 @@ preferred_addr: jmp *%eax ENDPROC(startup_32) +#ifdef CONFIG_EFI_STUB +/* + * We don't need the return address, so set up the stack so efi_main() can find + * its arguments. + */ +ENTRY(efi_pe_entry) + add $0x4, %esp + + call 1f +1: popl %esi + subl $1b, %esi + + popl %ecx + movl %ecx, efi32_config(%esi) /* Handle */ + popl %ecx + movl %ecx, efi32_config+8(%esi) /* EFI System table pointer */ + + /* Relocate efi_config->call() */ + leal efi32_config(%esi), %eax + add %esi, 40(%eax) + pushl %eax + + call make_boot_params + cmpl $0, %eax + je fail + movl %esi, BP_code32_start(%eax) + popl %ecx + pushl %eax + pushl %ecx + jmp 2f /* Skip efi_config initialization */ +ENDPROC(efi_pe_entry) + +ENTRY(efi32_stub_entry) + add $0x4, %esp + popl %ecx + popl %edx + + call 1f +1: popl %esi + subl $1b, %esi + + movl %ecx, efi32_config(%esi) /* Handle */ + movl %edx, efi32_config+8(%esi) /* EFI System table pointer */ + + /* Relocate efi_config->call() */ + leal efi32_config(%esi), %eax + add %esi, 40(%eax) + pushl %eax +2: + call efi_main + cmpl $0, %eax + movl %eax, %esi + jne 2f +fail: + /* EFI init failed, so hang. */ + hlt + jmp fail +2: + movl BP_code32_start(%esi), %eax + leal startup_32(%eax), %eax + jmp *%eax +ENDPROC(efi32_stub_entry) +#endif + .text relocated: -- 2.12.2