From: Jiri Slaby <jslaby@suse.cz>
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 <jslaby@suse.cz>
Subject: [PATCH v9 11/28] x86/asm/head: Annotate data appropriately
Date: Fri, 11 Oct 2019 13:50:51 +0200 [thread overview]
Message-ID: <20191011115108.12392-12-jslaby@suse.cz> (raw)
In-Reply-To: <20191011115108.12392-1-jslaby@suse.cz>
Use the new SYM_DATA, SYM_DATA_START, and SYM_DATA_END in both 32 and 64
bit head_*.S. 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
had 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 now.
Note that the patch removes implicit 16B alignment previously inserted
by ENTRY:
* initial_code, setup_once_ref, initial_page_table, initial_stack,
boot_gdt are still aligned
* early_gdt_descr is now properly aligned as was intended before ENTRY
was added there long time ago
* phys_base's alignment is kept by an explicitly added new alignment
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
---
Notes:
[v9] preserve phys_base's alignment
arch/x86/kernel/head_32.S | 35 ++++++++--------
arch/x86/kernel/head_64.S | 87 +++++++++++++++++++++------------------
2 files changed, 65 insertions(+), 57 deletions(-)
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index aec1fdb80221..e2b3e6cf86ca 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -502,15 +502,12 @@ ENDPROC(early_ignore_irq)
__INITDATA
.align 4
-GLOBAL(early_recursion_flag)
- .long 0
+SYM_DATA(early_recursion_flag, .long 0)
__REFDATA
.align 4
-ENTRY(initial_code)
- .long i386_start_kernel
-ENTRY(setup_once_ref)
- .long setup_once
+SYM_DATA(initial_code, .long i386_start_kernel)
+SYM_DATA(setup_once_ref, .long setup_once)
#ifdef CONFIG_PAGE_TABLE_ISOLATION
#define PGD_ALIGN (2 * PAGE_SIZE)
@@ -553,7 +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
@@ -571,17 +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 +598,25 @@ 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_LOCAL(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 5b42552d929f..8b0926ac4ac6 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
@@ -335,9 +333,9 @@ SYM_CODE_START_LOCAL(early_idt_handler_common)
jmp restore_regs_and_return_to_kernel
SYM_CODE_END(early_idt_handler_common)
-#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
/*
@@ -352,11 +350,11 @@ 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
@@ -371,20 +369,21 @@ GLOBAL(name)
__INITDATA
.balign 4
-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)
-GLOBAL(early_recursion_flag)
- .long 0
+SYM_DATA(early_recursion_flag, .long 0)
.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
@@ -392,11 +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.
@@ -406,25 +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.
@@ -441,8 +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)
@@ -452,31 +458,32 @@ 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)
-
-ENTRY(phys_base)
- /* This must match the first entry in level2_kernel_pgt */
- .quad 0x0000000000000000
+
+SYM_DATA(early_gdt_descr, .word GDT_ENTRIES*8-1)
+SYM_DATA_LOCAL(early_gdt_descr_base, .quad INIT_PER_CPU_VAR(gdt_page))
+
+ .align 16
+/* This must match the first entry in level2_kernel_pgt */
+SYM_DATA(phys_base, .quad 0x0)
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)
--
2.23.0
next prev parent reply other threads:[~2019-10-11 11:52 UTC|newest]
Thread overview: 79+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-11 11:50 [PATCH v9 00/28] New macros for assembler symbols Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 01/28] linkage: Introduce new " Jiri Slaby
2019-10-14 9:31 ` Rafael J. Wysocki
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 02/28] x86/asm/suspend: Use SYM_DATA for data Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 03/28] x86/asm: Annotate relocate_kernel_{32,64}.c Jiri Slaby
2019-10-14 13:15 ` Borislav Petkov
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 04/28] x86/asm/entry: Annotate THUNKs Jiri Slaby
2019-10-14 13:38 ` Borislav Petkov
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 05/28] x86/asm: Annotate local pseudo-functions Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 06/28] x86/asm/crypto: Annotate local functions Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 07/28] x86/boot: " Jiri Slaby
2019-10-14 14:27 ` Borislav Petkov
2019-10-15 5:43 ` Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 08/28] x86/uaccess: Annotate local function Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 09/28] x86/asm: Annotate aliases Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 10/28] x86/asm/entry: Annotate interrupt symbols properly Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` Jiri Slaby [this message]
2019-10-18 16:30 ` [tip: x86/asm] x86/asm/head: Annotate data appropriately tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 12/28] x86/boot: " Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 13/28] um: " Jiri Slaby
2019-10-15 15:37 ` Richard Weinberger
2019-10-18 16:30 ` [tip: x86/asm] x86/um: " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 14/28] xen/pvh: " Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 15/28] x86/asm/purgatory: Start using annotations Jiri Slaby
2019-10-15 17:03 ` Borislav Petkov
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 16/28] x86/asm: Do not annotate functions by GLOBAL Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] x86/asm: Do not annotate functions with GLOBAL tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 17/28] x86/asm: Use SYM_INNER_LABEL instead of GLOBAL Jiri Slaby
2019-10-15 17:31 ` Borislav Petkov
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 18/28] x86/asm/realmode: Use SYM_DATA_* " Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:50 ` [PATCH v9 19/28] x86/asm: Kill the last GLOBAL user and remove the macro Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] x86/asm: Remove " tip-bot2 for Jiri Slaby
2019-10-11 11:51 ` [PATCH v9 20/28] x86/asm: Make some functions local Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-11 11:51 ` [PATCH v9 21/28] x86/asm/ftrace: Mark function_hook as function Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
2019-10-18 16:48 ` Steven Rostedt
2019-10-18 16:49 ` Steven Rostedt
2019-10-18 17:13 ` Borislav Petkov
2019-10-18 17:37 ` Steven Rostedt
2019-10-18 19:48 ` Borislav Petkov
2019-10-18 20:31 ` Steven Rostedt
2019-10-19 7:34 ` Borislav Petkov
2019-10-21 14:10 ` [PATCH] x86/ftrace: Get rid of function_hook Borislav Petkov
2019-10-21 14:33 ` Steven Rostedt
2019-10-22 11:38 ` Jiri Slaby
2019-10-22 12:56 ` Borislav Petkov
2019-10-22 12:57 ` [PATCH -v2] " Borislav Petkov
2019-10-25 9:00 ` [tip: x86/asm] " tip-bot2 for Borislav Petkov
2019-10-11 11:51 ` [PATCH v9 22/28] x86_64/asm: Add ENDs to some functions and relabel with SYM_CODE_* Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] x86/asm/64: " tip-bot2 for Jiri Slaby
2019-10-11 11:51 ` [PATCH v9 23/28] x86_64/asm: Change all ENTRY+END to SYM_CODE_* Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] x86/asm/64: " tip-bot2 for Jiri Slaby
2019-10-11 11:51 ` [PATCH v9 24/28] x86_64/asm: Change all ENTRY+ENDPROC to SYM_FUNC_* Jiri Slaby
2019-10-16 7:12 ` Borislav Petkov
2019-10-18 6:56 ` Herbert Xu
2019-10-11 11:51 ` [PATCH v9 25/28] x86_32/asm: Add ENDs to some functions and relabel with SYM_CODE_* Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] x86/asm/32: " tip-bot2 for Jiri Slaby
2019-10-11 11:51 ` [PATCH v9 26/28] x86_32/asm: Change all ENTRY+END to SYM_CODE_* Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] x86/asm/32: " tip-bot2 for Jiri Slaby
2019-10-11 11:51 ` [PATCH v9 27/28] x86_32/asm: Change all ENTRY+ENDPROC to SYM_FUNC_* Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] x86/asm/32: " tip-bot2 for Jiri Slaby
2019-10-11 11:51 ` [PATCH v9 28/28] x86/asm: Replace WEAK uses by SYM_INNER_LABEL_ALIGN Jiri Slaby
2019-10-18 16:30 ` [tip: x86/asm] " tip-bot2 for Jiri Slaby
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