From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DC49C433FF for ; Thu, 8 Aug 2019 10:39:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6E1D3218BA for ; Thu, 8 Aug 2019 10:39:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403871AbfHHKjM (ORCPT ); Thu, 8 Aug 2019 06:39:12 -0400 Received: from mx2.suse.de ([195.135.220.15]:47612 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2403812AbfHHKjG (ORCPT ); Thu, 8 Aug 2019 06:39:06 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id D4754AFE3; Thu, 8 Aug 2019 10:39:03 +0000 (UTC) From: Jiri Slaby To: bp@alien8.de Cc: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Jiri Slaby Subject: [PATCH v8 11/28] x86/asm/head: annotate data appropriatelly Date: Thu, 8 Aug 2019 12:38:37 +0200 Message-Id: <20190808103854.6192-12-jslaby@suse.cz> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190808103854.6192-1-jslaby@suse.cz> References: <20190808103854.6192-1-jslaby@suse.cz> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use the new SYM_DATA, SYM_DATA_START, and SYM_DATA_END in both 32 and 64 bit heads. In the 64-bit version, define also SYM_DATA_START_PAGE_ALIGNED locally using the new SYM_START. It is used in the code instead of NEXT_PAGE() which was defined in this file and has been using the obsolete macro GLOBAL(). Now, the data in the 64-bit object file look sane: Value Size Type Bind Vis Ndx Name 0000 4096 OBJECT GLOBAL DEFAULT 15 init_level4_pgt 1000 4096 OBJECT GLOBAL DEFAULT 15 level3_kernel_pgt 2000 2048 OBJECT GLOBAL DEFAULT 15 level2_kernel_pgt 3000 4096 OBJECT GLOBAL DEFAULT 15 level2_fixmap_pgt 4000 4096 OBJECT GLOBAL DEFAULT 15 level1_fixmap_pgt 5000 2 OBJECT GLOBAL DEFAULT 15 early_gdt_descr 5002 8 OBJECT LOCAL DEFAULT 15 early_gdt_descr_base 500a 8 OBJECT GLOBAL DEFAULT 15 phys_base 0000 8 OBJECT GLOBAL DEFAULT 17 initial_code 0008 8 OBJECT GLOBAL DEFAULT 17 initial_gs 0010 8 OBJECT GLOBAL DEFAULT 17 initial_stack 0000 4 OBJECT GLOBAL DEFAULT 19 early_recursion_flag 1000 4096 OBJECT GLOBAL DEFAULT 19 early_level4_pgt 2000 0x40000 OBJECT GLOBAL DEFAULT 19 early_dynamic_pgts 0000 4096 OBJECT GLOBAL DEFAULT 22 empty_zero_page All have correct size and type. Note, that we can now see that it might be worth pushing early_recursion_flag after early_dynamic_pgts -- we are wasting almost 4K of .init.data. Signed-off-by: Jiri Slaby Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: x86@kernel.org --- arch/x86/kernel/head_32.S | 29 ++++++++------- arch/x86/kernel/head_64.S | 78 +++++++++++++++++++++------------------ 2 files changed, 58 insertions(+), 49 deletions(-) diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 0bae769b7b59..2d5390d84467 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -502,8 +502,7 @@ ENDPROC(early_ignore_irq) __INITDATA .align 4 -GLOBAL(early_recursion_flag) - .long 0 +SYM_DATA(early_recursion_flag, .long 0) __REFDATA .align 4 @@ -551,7 +550,7 @@ EXPORT_SYMBOL(empty_zero_page) __PAGE_ALIGNED_DATA /* Page-aligned for the benefit of paravirt? */ .align PGD_ALIGN -ENTRY(initial_page_table) +SYM_DATA_START(initial_page_table) .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 /* low identity map */ # if KPMDS == 3 .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 @@ -569,17 +568,18 @@ ENTRY(initial_page_table) # error "Kernel PMDs should be 1, 2 or 3" # endif .align PAGE_SIZE /* needs to be page-sized too */ +SYM_DATA_END(initial_page_table) #endif .data .balign 4 -ENTRY(initial_stack) - /* - * The SIZEOF_PTREGS gap is a convention which helps the in-kernel - * unwinder reliably detect the end of the stack. - */ - .long init_thread_union + THREAD_SIZE - SIZEOF_PTREGS - \ - TOP_OF_KERNEL_STACK_PADDING; +/* + * The SIZEOF_PTREGS gap is a convention which helps the in-kernel unwinder + * reliably detect the end of the stack. + */ +SYM_DATA(initial_stack, + .long init_thread_union + THREAD_SIZE - + SIZEOF_PTREGS - TOP_OF_KERNEL_STACK_PADDING) __INITRODATA int_msg: @@ -600,22 +600,25 @@ int_msg: ALIGN # early boot GDT descriptor (must use 1:1 address mapping) .word 0 # 32 bit align gdt_desc.address -boot_gdt_descr: +SYM_DATA_START(boot_gdt_descr) .word __BOOT_DS+7 .long boot_gdt - __PAGE_OFFSET +SYM_DATA_END(boot_gdt_descr) # boot GDT descriptor (later on used by CPU#0): .word 0 # 32 bit align gdt_desc.address -ENTRY(early_gdt_descr) +SYM_DATA_START(early_gdt_descr) .word GDT_ENTRIES*8-1 .long gdt_page /* Overwritten for secondary CPUs */ +SYM_DATA_END(early_gdt_descr) /* * The boot_gdt must mirror the equivalent in setup.S and is * used only for booting. */ .align L1_CACHE_BYTES -ENTRY(boot_gdt) +SYM_DATA_START(boot_gdt) .fill GDT_ENTRY_BOOT_CS,8,0 .quad 0x00cf9a000000ffff /* kernel 4GB code at 0x00000000 */ .quad 0x00cf92000000ffff /* kernel 4GB data at 0x00000000 */ +SYM_DATA_END(boot_gdt) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 6fedcda37634..6661c76a2049 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -260,16 +260,14 @@ END(start_cpu0) /* Both SMP bootup and ACPI suspend change these variables */ __REFDATA .balign 8 - GLOBAL(initial_code) - .quad x86_64_start_kernel - GLOBAL(initial_gs) - .quad INIT_PER_CPU_VAR(fixed_percpu_data) - GLOBAL(initial_stack) - /* - * The SIZEOF_PTREGS gap is a convention which helps the in-kernel - * unwinder reliably detect the end of the stack. - */ - .quad init_thread_union + THREAD_SIZE - SIZEOF_PTREGS +SYM_DATA(initial_code, .quad x86_64_start_kernel) +SYM_DATA(initial_gs, .quad INIT_PER_CPU_VAR(fixed_percpu_data)) +/* + * The SIZEOF_PTREGS gap is a convention which helps the in-kernel unwinder + * reliably detect the end of the stack. + */ +SYM_DATA(initial_stack, + .quad init_thread_union + THREAD_SIZE - SIZEOF_PTREGS) __FINITDATA __INIT @@ -338,12 +336,10 @@ SYM_CODE_END(early_idt_handler_common) __INITDATA .balign 4 -GLOBAL(early_recursion_flag) - .long 0 +SYM_DATA(early_recursion_flag, .long 0) -#define NEXT_PAGE(name) \ - .balign PAGE_SIZE; \ -GLOBAL(name) +#define SYM_DATA_START_PAGE_ALIGNED(name) \ + SYM_START(name, SYM_L_GLOBAL, .balign PAGE_SIZE) #ifdef CONFIG_PAGE_TABLE_ISOLATION /* @@ -358,11 +354,11 @@ GLOBAL(name) */ #define PTI_USER_PGD_FILL 512 /* This ensures they are 8k-aligned: */ -#define NEXT_PGD_PAGE(name) \ - .balign 2 * PAGE_SIZE; \ -GLOBAL(name) +#define SYM_DATA_START_PTI_ALIGNED(name) \ + SYM_START(name, SYM_L_GLOBAL, .balign 2 * PAGE_SIZE) #else -#define NEXT_PGD_PAGE(name) NEXT_PAGE(name) +#define SYM_DATA_START_PTI_ALIGNED(name) \ + SYM_DATA_START_PAGE_ALIGNED(name) #define PTI_USER_PGD_FILL 0 #endif @@ -375,17 +371,19 @@ GLOBAL(name) .endr __INITDATA -NEXT_PGD_PAGE(early_top_pgt) +SYM_DATA_START_PTI_ALIGNED(early_top_pgt) .fill 512,8,0 .fill PTI_USER_PGD_FILL,8,0 +SYM_DATA_END(early_top_pgt) -NEXT_PAGE(early_dynamic_pgts) +SYM_DATA_START_PAGE_ALIGNED(early_dynamic_pgts) .fill 512*EARLY_DYNAMIC_PAGE_TABLES,8,0 +SYM_DATA_END(early_dynamic_pgts) .data #if defined(CONFIG_XEN_PV) || defined(CONFIG_PVH) -NEXT_PGD_PAGE(init_top_pgt) +SYM_DATA_START_PTI_ALIGNED(init_top_pgt) .quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC .org init_top_pgt + L4_PAGE_OFFSET*8, 0 .quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC @@ -393,11 +391,13 @@ NEXT_PGD_PAGE(init_top_pgt) /* (2^48-(2*1024*1024*1024))/(2^39) = 511 */ .quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC .fill PTI_USER_PGD_FILL,8,0 +SYM_DATA_END(init_top_pgt) -NEXT_PAGE(level3_ident_pgt) +SYM_DATA_START_PAGE_ALIGNED(level3_ident_pgt) .quad level2_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC .fill 511, 8, 0 -NEXT_PAGE(level2_ident_pgt) +SYM_DATA_END(level3_ident_pgt) +SYM_DATA_START_PAGE_ALIGNED(level2_ident_pgt) /* * Since I easily can, map the first 1G. * Don't set NX because code runs from these pages. @@ -407,25 +407,29 @@ NEXT_PAGE(level2_ident_pgt) * the CPU should ignore the bit. */ PMDS(0, __PAGE_KERNEL_IDENT_LARGE_EXEC, PTRS_PER_PMD) +SYM_DATA_END(level2_ident_pgt) #else -NEXT_PGD_PAGE(init_top_pgt) +SYM_DATA_START_PTI_ALIGNED(init_top_pgt) .fill 512,8,0 .fill PTI_USER_PGD_FILL,8,0 +SYM_DATA_END(init_top_pgt) #endif #ifdef CONFIG_X86_5LEVEL -NEXT_PAGE(level4_kernel_pgt) +SYM_DATA_START_PAGE_ALIGNED(level4_kernel_pgt) .fill 511,8,0 .quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC +SYM_DATA_END(level4_kernel_pgt) #endif -NEXT_PAGE(level3_kernel_pgt) +SYM_DATA_START_PAGE_ALIGNED(level3_kernel_pgt) .fill L3_START_KERNEL,8,0 /* (2^48-(2*1024*1024*1024)-((2^39)*511))/(2^30) = 510 */ .quad level2_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE_NOENC .quad level2_fixmap_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC +SYM_DATA_END(level3_kernel_pgt) -NEXT_PAGE(level2_kernel_pgt) +SYM_DATA_START_PAGE_ALIGNED(level2_kernel_pgt) /* * 512 MB kernel mapping. We spend a full page on this pagetable * anyway. @@ -442,8 +446,9 @@ NEXT_PAGE(level2_kernel_pgt) */ PMDS(0, __PAGE_KERNEL_LARGE_EXEC, KERNEL_IMAGE_SIZE/PMD_SIZE) +SYM_DATA_END(level2_kernel_pgt) -NEXT_PAGE(level2_fixmap_pgt) +SYM_DATA_START_PAGE_ALIGNED(level2_fixmap_pgt) .fill (512 - 4 - FIXMAP_PMD_NUM),8,0 pgtno = 0 .rept (FIXMAP_PMD_NUM) @@ -453,21 +458,21 @@ NEXT_PAGE(level2_fixmap_pgt) .endr /* 6 MB reserved space + a 2MB hole */ .fill 4,8,0 +SYM_DATA_END(level2_fixmap_pgt) -NEXT_PAGE(level1_fixmap_pgt) +SYM_DATA_START_PAGE_ALIGNED(level1_fixmap_pgt) .rept (FIXMAP_PMD_NUM) .fill 512,8,0 .endr +SYM_DATA_END(level1_fixmap_pgt) #undef PMDS .data .align 16 - .globl early_gdt_descr -early_gdt_descr: - .word GDT_ENTRIES*8-1 -early_gdt_descr_base: - .quad INIT_PER_CPU_VAR(gdt_page) + +SYM_DATA(early_gdt_descr, .word GDT_ENTRIES*8-1) +SYM_DATA_LOCAL(early_gdt_descr_base, .quad INIT_PER_CPU_VAR(gdt_page)) /* This must match the first entry in level2_kernel_pgt */ SYM_DATA(phys_base, .quad 0x0000000000000000) @@ -476,7 +481,8 @@ EXPORT_SYMBOL(phys_base) #include "../../x86/xen/xen-head.S" __PAGE_ALIGNED_BSS -NEXT_PAGE(empty_zero_page) +SYM_DATA_START_PAGE_ALIGNED(empty_zero_page) .skip PAGE_SIZE +SYM_DATA_END(empty_zero_page) EXPORT_SYMBOL(empty_zero_page) -- 2.22.0