From 4b89b7f7aad5742523db801b7107598e5b5a42c8 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 24 Nov 2016 03:41:41 +1100 Subject: [PATCH] kbuild: keep data tables through dead code elimination When CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is enabled we must ensure that we still keep various programatically-accessed tables. [npiggin: Fold Paul's patches into one, and add a few more tables. diff symbol tables of allyesconfig with/without -gc-sections shows up lost tables quite easily.] Signed-off-by: Paul Burton Signed-off-by: Nicholas Piggin Signed-off-by: Michal Marek --- include/asm-generic/vmlinux.lds.h | 68 +++++++++++++++---------------- 1 file changed, 34 insertions(+), 34 deletions(-) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 30747960bc54..5372775161d0 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -114,7 +114,7 @@ #ifdef CONFIG_KPROBES #define KPROBE_BLACKLIST() . = ALIGN(8); \ VMLINUX_SYMBOL(__start_kprobe_blacklist) = .; \ - *(_kprobe_blacklist) \ + KEEP(*(_kprobe_blacklist)) \ VMLINUX_SYMBOL(__stop_kprobe_blacklist) = .; #else #define KPROBE_BLACKLIST() @@ -123,10 +123,10 @@ #ifdef CONFIG_EVENT_TRACING #define FTRACE_EVENTS() . = ALIGN(8); \ VMLINUX_SYMBOL(__start_ftrace_events) = .; \ - *(_ftrace_events) \ + KEEP(*(_ftrace_events)) \ VMLINUX_SYMBOL(__stop_ftrace_events) = .; \ VMLINUX_SYMBOL(__start_ftrace_enum_maps) = .; \ - *(_ftrace_enum_map) \ + KEEP(*(_ftrace_enum_map)) \ VMLINUX_SYMBOL(__stop_ftrace_enum_maps) = .; #else #define FTRACE_EVENTS() @@ -134,10 +134,10 @@ #ifdef CONFIG_TRACING #define TRACE_PRINTKS() VMLINUX_SYMBOL(__start___trace_bprintk_fmt) = .; \ - *(__trace_printk_fmt) /* Trace_printk fmt' pointer */ \ + KEEP(*(__trace_printk_fmt)) /* Trace_printk fmt' pointer */ \ VMLINUX_SYMBOL(__stop___trace_bprintk_fmt) = .; #define TRACEPOINT_STR() VMLINUX_SYMBOL(__start___tracepoint_str) = .; \ - *(__tracepoint_str) /* Trace_printk fmt' pointer */ \ + KEEP(*(__tracepoint_str)) /* Trace_printk fmt' pointer */ \ VMLINUX_SYMBOL(__stop___tracepoint_str) = .; #else #define TRACE_PRINTKS() @@ -147,7 +147,7 @@ #ifdef CONFIG_FTRACE_SYSCALLS #define TRACE_SYSCALLS() . = ALIGN(8); \ VMLINUX_SYMBOL(__start_syscalls_metadata) = .; \ - *(__syscalls_metadata) \ + KEEP(*(__syscalls_metadata)) \ VMLINUX_SYMBOL(__stop_syscalls_metadata) = .; #else #define TRACE_SYSCALLS() @@ -156,7 +156,7 @@ #ifdef CONFIG_SERIAL_EARLYCON #define EARLYCON_TABLE() STRUCT_ALIGN(); \ VMLINUX_SYMBOL(__earlycon_table) = .; \ - *(__earlycon_table) \ + KEEP(*(__earlycon_table)) \ VMLINUX_SYMBOL(__earlycon_table_end) = .; #else #define EARLYCON_TABLE() @@ -169,8 +169,8 @@ #define _OF_TABLE_1(name) \ . = ALIGN(8); \ VMLINUX_SYMBOL(__##name##_of_table) = .; \ - *(__##name##_of_table) \ - *(__##name##_of_table_end) + KEEP(*(__##name##_of_table)) \ + KEEP(*(__##name##_of_table_end)) #define CLKSRC_OF_TABLES() OF_TABLE(CONFIG_CLKSRC_OF, clksrc) #define IRQCHIP_OF_MATCH_TABLE() OF_TABLE(CONFIG_IRQCHIP, irqchip) @@ -184,7 +184,7 @@ #define ACPI_PROBE_TABLE(name) \ . = ALIGN(8); \ VMLINUX_SYMBOL(__##name##_acpi_probe_table) = .; \ - *(__##name##_acpi_probe_table) \ + KEEP(*(__##name##_acpi_probe_table)) \ VMLINUX_SYMBOL(__##name##_acpi_probe_table_end) = .; #else #define ACPI_PROBE_TABLE(name) @@ -193,7 +193,7 @@ #define KERNEL_DTB() \ STRUCT_ALIGN(); \ VMLINUX_SYMBOL(__dtb_start) = .; \ - *(.dtb.init.rodata) \ + KEEP(*(.dtb.init.rodata)) \ VMLINUX_SYMBOL(__dtb_end) = .; /* @@ -214,11 +214,11 @@ /* implement dynamic printk debug */ \ . = ALIGN(8); \ VMLINUX_SYMBOL(__start___jump_table) = .; \ - *(__jump_table) \ + KEEP(*(__jump_table)) \ VMLINUX_SYMBOL(__stop___jump_table) = .; \ . = ALIGN(8); \ VMLINUX_SYMBOL(__start___verbose) = .; \ - *(__verbose) \ + KEEP(*(__verbose)) \ VMLINUX_SYMBOL(__stop___verbose) = .; \ LIKELY_PROFILE() \ BRANCH_PROFILE() \ @@ -271,10 +271,10 @@ VMLINUX_SYMBOL(__start_rodata) = .; \ *(.rodata) *(.rodata.*) \ RO_AFTER_INIT_DATA /* Read only after init */ \ - *(__vermagic) /* Kernel version magic */ \ + KEEP(*(__vermagic)) /* Kernel version magic */ \ . = ALIGN(8); \ VMLINUX_SYMBOL(__start___tracepoints_ptrs) = .; \ - *(__tracepoints_ptrs) /* Tracepoints: pointer array */\ + KEEP(*(__tracepoints_ptrs)) /* Tracepoints: pointer array */ \ VMLINUX_SYMBOL(__stop___tracepoints_ptrs) = .; \ *(__tracepoints_strings)/* Tracepoints: strings */ \ } \ @@ -288,35 +288,35 @@ /* PCI quirks */ \ .pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__start_pci_fixups_early) = .; \ - *(.pci_fixup_early) \ + KEEP(*(.pci_fixup_early)) \ VMLINUX_SYMBOL(__end_pci_fixups_early) = .; \ VMLINUX_SYMBOL(__start_pci_fixups_header) = .; \ - *(.pci_fixup_header) \ + KEEP(*(.pci_fixup_header)) \ VMLINUX_SYMBOL(__end_pci_fixups_header) = .; \ VMLINUX_SYMBOL(__start_pci_fixups_final) = .; \ - *(.pci_fixup_final) \ + KEEP(*(.pci_fixup_final)) \ VMLINUX_SYMBOL(__end_pci_fixups_final) = .; \ VMLINUX_SYMBOL(__start_pci_fixups_enable) = .; \ - *(.pci_fixup_enable) \ + KEEP(*(.pci_fixup_enable)) \ VMLINUX_SYMBOL(__end_pci_fixups_enable) = .; \ VMLINUX_SYMBOL(__start_pci_fixups_resume) = .; \ - *(.pci_fixup_resume) \ + KEEP(*(.pci_fixup_resume)) \ VMLINUX_SYMBOL(__end_pci_fixups_resume) = .; \ VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .; \ - *(.pci_fixup_resume_early) \ + KEEP(*(.pci_fixup_resume_early)) \ VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .; \ VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .; \ - *(.pci_fixup_suspend) \ + KEEP(*(.pci_fixup_suspend)) \ VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .; \ VMLINUX_SYMBOL(__start_pci_fixups_suspend_late) = .; \ - *(.pci_fixup_suspend_late) \ + KEEP(*(.pci_fixup_suspend_late)) \ VMLINUX_SYMBOL(__end_pci_fixups_suspend_late) = .; \ } \ \ /* Built-in firmware blobs */ \ .builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__start_builtin_fw) = .; \ - *(.builtin_fw) \ + KEEP(*(.builtin_fw)) \ VMLINUX_SYMBOL(__end_builtin_fw) = .; \ } \ \ @@ -394,7 +394,7 @@ \ /* Kernel symbol table: strings */ \ __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \ - KEEP(*(__ksymtab_strings)) \ + *(__ksymtab_strings) \ } \ \ /* __*init sections */ \ @@ -407,14 +407,14 @@ /* Built-in module parameters. */ \ __param : AT(ADDR(__param) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__start___param) = .; \ - *(__param) \ + KEEP(*(__param)) \ VMLINUX_SYMBOL(__stop___param) = .; \ } \ \ /* Built-in module versions. */ \ __modver : AT(ADDR(__modver) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__start___modver) = .; \ - *(__modver) \ + KEEP(*(__modver)) \ VMLINUX_SYMBOL(__stop___modver) = .; \ . = ALIGN((align)); \ VMLINUX_SYMBOL(__end_rodata) = .; \ @@ -517,7 +517,7 @@ . = ALIGN(align); \ __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__start___ex_table) = .; \ - *(__ex_table) \ + KEEP(*(__ex_table)) \ VMLINUX_SYMBOL(__stop___ex_table) = .; \ } @@ -533,9 +533,9 @@ #ifdef CONFIG_CONSTRUCTORS #define KERNEL_CTORS() . = ALIGN(8); \ VMLINUX_SYMBOL(__ctors_start) = .; \ - *(.ctors) \ - *(SORT(.init_array.*)) \ - *(.init_array) \ + KEEP(*(.ctors)) \ + KEEP(*(SORT(.init_array.*))) \ + KEEP(*(.init_array)) \ VMLINUX_SYMBOL(__ctors_end) = .; #else #define KERNEL_CTORS() @@ -659,7 +659,7 @@ . = ALIGN(8); \ __bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__start___bug_table) = .; \ - *(__bug_table) \ + KEEP(*(__bug_table)) \ VMLINUX_SYMBOL(__stop___bug_table) = .; \ } #else @@ -671,7 +671,7 @@ . = ALIGN(4); \ .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__tracedata_start) = .; \ - *(.tracedata) \ + KEEP(*(.tracedata)) \ VMLINUX_SYMBOL(__tracedata_end) = .; \ } #else @@ -688,7 +688,7 @@ #define INIT_SETUP(initsetup_align) \ . = ALIGN(initsetup_align); \ VMLINUX_SYMBOL(__setup_start) = .; \ - *(.init.setup) \ + KEEP(*(.init.setup)) \ VMLINUX_SYMBOL(__setup_end) = .; #define INIT_CALLS_LEVEL(level) \ -- 2.20.1