target/linux/generic/patches-3.14/220-gc_sections.patch

   1 From: Felix Fietkau <nbd@openwrt.org>
   2
   3 use -ffunction-sections, -fdata-sections and --gc-sections
   4
   5 In combination with kernel symbol export stripping this significantly reduces
   6 the kernel image size. Used on both ARM and MIPS architectures.
   7
   8 Signed-off-by: Felix Fietkau <nbd@openwrt.org>
   9 Signed-off-by: Jonas Gorski <jogo@openwrt.org>
  10 Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
  11 ---
  12
  13 --- a/arch/mips/Makefile
  14 +++ b/arch/mips/Makefile
  15 @@ -89,10 +89,14 @@ all-$(CONFIG_SYS_SUPPORTS_ZBOOT)+= vmlin
  16  #
  17  cflags-y                       += -G 0 -mno-abicalls -fno-pic -pipe
  18  cflags-y                       += -msoft-float
  19 -LDFLAGS_vmlinux                        += -G 0 -static -n -nostdlib
  20 +LDFLAGS_vmlinux                        += -G 0 -static -n -nostdlib --gc-sections
  21  KBUILD_AFLAGS_MODULE           += -mlong-calls
  22  KBUILD_CFLAGS_MODULE           += -mlong-calls
  23
  24 +ifndef CONFIG_FUNCTION_TRACER
  25 +KBUILD_CFLAGS_KERNEL           += -ffunction-sections -fdata-sections
  26 +endif
  27 +
  28  cflags-y += -ffreestanding
  29
  30  #
  31 --- a/arch/mips/kernel/vmlinux.lds.S
  32 +++ b/arch/mips/kernel/vmlinux.lds.S
  33 @@ -67,7 +67,7 @@ SECTIONS
  34         /* Exception table for data bus errors */
  35         __dbe_table : {
  36                 __start___dbe_table = .;
  37 -               *(__dbe_table)
  38 +               KEEP(*(__dbe_table))
  39                 __stop___dbe_table = .;
  40         }
  41
  42 @@ -112,7 +112,7 @@ SECTIONS
  43         . = ALIGN(4);
  44         .mips.machines.init : AT(ADDR(.mips.machines.init) - LOAD_OFFSET) {
  45                 __mips_machines_start = .;
  46 -               *(.mips.machines.init)
  47 +               KEEP(*(.mips.machines.init))
  48                 __mips_machines_end = .;
  49         }
  50
  51 --- a/include/asm-generic/vmlinux.lds.h
  52 +++ b/include/asm-generic/vmlinux.lds.h
  53 @@ -87,7 +87,7 @@
  54  #ifdef CONFIG_FTRACE_MCOUNT_RECORD
  55  #define MCOUNT_REC()   . = ALIGN(8);                           \
  56                         VMLINUX_SYMBOL(__start_mcount_loc) = .; \
  57 -                       *(__mcount_loc)                         \
  58 +                       KEEP(*(__mcount_loc))                   \
  59                         VMLINUX_SYMBOL(__stop_mcount_loc) = .;
  60  #else
  61  #define MCOUNT_REC()
  62 @@ -95,7 +95,7 @@
  63
  64  #ifdef CONFIG_TRACE_BRANCH_PROFILING
  65  #define LIKELY_PROFILE()       VMLINUX_SYMBOL(__start_annotated_branch_profile) = .; \
  66 -                               *(_ftrace_annotated_branch)                           \
  67 +                               KEEP(*(_ftrace_annotated_branch))                     \
  68                                 VMLINUX_SYMBOL(__stop_annotated_branch_profile) = .;
  69  #else
  70  #define LIKELY_PROFILE()
  71 @@ -103,7 +103,7 @@
  72
  73  #ifdef CONFIG_PROFILE_ALL_BRANCHES
  74  #define BRANCH_PROFILE()       VMLINUX_SYMBOL(__start_branch_profile) = .;   \
  75 -                               *(_ftrace_branch)                             \
  76 +                               KEEP(*(_ftrace_branch))                       \
  77                                 VMLINUX_SYMBOL(__stop_branch_profile) = .;
  78  #else
  79  #define BRANCH_PROFILE()
  80 @@ -112,7 +112,7 @@
  81  #ifdef CONFIG_EVENT_TRACING
  82  #define FTRACE_EVENTS()        . = ALIGN(8);                                   \
  83                         VMLINUX_SYMBOL(__start_ftrace_events) = .;      \
  84 -                       *(_ftrace_events)                               \
  85 +                       KEEP(*(_ftrace_events))                         \
  86                         VMLINUX_SYMBOL(__stop_ftrace_events) = .;
  87  #else
  88  #define FTRACE_EVENTS()
  89 @@ -120,7 +120,7 @@
  90
  91  #ifdef CONFIG_TRACING
  92  #define TRACE_PRINTKS() VMLINUX_SYMBOL(__start___trace_bprintk_fmt) = .;      \
  93 -                        *(__trace_printk_fmt) /* Trace_printk fmt' pointer */ \
  94 +                        KEEP(*(__trace_printk_fmt)) /* Trace_printk fmt' pointer */ \
  95                          VMLINUX_SYMBOL(__stop___trace_bprintk_fmt) = .;
  96  #define TRACEPOINT_STR() VMLINUX_SYMBOL(__start___tracepoint_str) = .; \
  97                          *(__tracepoint_str) /* Trace_printk fmt' pointer */ \
  98 @@ -133,7 +133,7 @@
  99  #ifdef CONFIG_FTRACE_SYSCALLS
 100  #define TRACE_SYSCALLS() . = ALIGN(8);                                 \
 101                          VMLINUX_SYMBOL(__start_syscalls_metadata) = .; \
 102 -                        *(__syscalls_metadata)                         \
 103 +                        KEEP(*(__syscalls_metadata))                   \
 104                          VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
 105  #else
 106  #define TRACE_SYSCALLS()
 107 @@ -142,8 +142,8 @@
 108  #ifdef CONFIG_CLKSRC_OF
 109  #define CLKSRC_OF_TABLES() . = ALIGN(8);                               \
 110                            VMLINUX_SYMBOL(__clksrc_of_table) = .;       \
 111 -                          *(__clksrc_of_table)                         \
 112 -                          *(__clksrc_of_table_end)
 113 +                          KEEP(*(__clksrc_of_table))                   \
 114 +                          KEEP(*(__clksrc_of_table_end))
 115  #else
 116  #define CLKSRC_OF_TABLES()
 117  #endif
 118 @@ -152,8 +152,8 @@
 119  #define IRQCHIP_OF_MATCH_TABLE()                                       \
 120         . = ALIGN(8);                                                   \
 121         VMLINUX_SYMBOL(__irqchip_begin) = .;                            \
 122 -       *(__irqchip_of_table)                                           \
 123 -       *(__irqchip_of_end)
 124 +       KEEP(*(__irqchip_of_table))                                     \
 125 +       KEEP(*(__irqchip_of_end))
 126  #else
 127  #define IRQCHIP_OF_MATCH_TABLE()
 128  #endif
 129 @@ -161,8 +161,8 @@
 130  #ifdef CONFIG_COMMON_CLK
 131  #define CLK_OF_TABLES() . = ALIGN(8);                          \
 132                         VMLINUX_SYMBOL(__clk_of_table) = .;     \
 133 -                       *(__clk_of_table)                       \
 134 -                       *(__clk_of_table_end)
 135 +                       KEEP(*(__clk_of_table))                 \
 136 +                       KEEP(*(__clk_of_table_end))
 137  #else
 138  #define CLK_OF_TABLES()
 139  #endif
 140 @@ -170,7 +170,7 @@
 141  #define KERNEL_DTB()                                                   \
 142         STRUCT_ALIGN();                                                 \
 143         VMLINUX_SYMBOL(__dtb_start) = .;                                \
 144 -       *(.dtb.init.rodata)                                             \
 145 +       KEEP(*(.dtb.init.rodata))                                       \
 146         VMLINUX_SYMBOL(__dtb_end) = .;
 147
 148  /* .data section */
 149 @@ -186,16 +186,17 @@
 150         /* implement dynamic printk debug */                            \
 151         . = ALIGN(8);                                                   \
 152         VMLINUX_SYMBOL(__start___jump_table) = .;                       \
 153 -       *(__jump_table)                                                 \
 154 +       KEEP(*(__jump_table))                                           \
 155         VMLINUX_SYMBOL(__stop___jump_table) = .;                        \
 156         . = ALIGN(8);                                                   \
 157         VMLINUX_SYMBOL(__start___verbose) = .;                          \
 158 -       *(__verbose)                                                    \
 159 +       KEEP(*(__verbose))                                              \
 160         VMLINUX_SYMBOL(__stop___verbose) = .;                           \
 161         LIKELY_PROFILE()                                                \
 162         BRANCH_PROFILE()                                                \
 163         TRACE_PRINTKS()                                                 \
 164 -       TRACEPOINT_STR()
 165 +       TRACEPOINT_STR()                                                \
 166 +       *(.data.[a-zA-Z_]*)
 167
 168  /*
 169   * Data section helpers
 170 @@ -249,32 +250,32 @@
 171         /* PCI quirks */                                                \
 172         .pci_fixup        : AT(ADDR(.pci_fixup) - LOAD_OFFSET) {        \
 173                 VMLINUX_SYMBOL(__start_pci_fixups_early) = .;           \
 174 -               *(.pci_fixup_early)                                     \
 175 +               KEEP(*(.pci_fixup_early))                               \
 176                 VMLINUX_SYMBOL(__end_pci_fixups_early) = .;             \
 177                 VMLINUX_SYMBOL(__start_pci_fixups_header) = .;          \
 178 -               *(.pci_fixup_header)                                    \
 179 +               KEEP(*(.pci_fixup_header))                              \
 180                 VMLINUX_SYMBOL(__end_pci_fixups_header) = .;            \
 181                 VMLINUX_SYMBOL(__start_pci_fixups_final) = .;           \
 182 -               *(.pci_fixup_final)                                     \
 183 +               KEEP(*(.pci_fixup_final))                               \
 184                 VMLINUX_SYMBOL(__end_pci_fixups_final) = .;             \
 185                 VMLINUX_SYMBOL(__start_pci_fixups_enable) = .;          \
 186 -               *(.pci_fixup_enable)                                    \
 187 +               KEEP(*(.pci_fixup_enable))                              \
 188                 VMLINUX_SYMBOL(__end_pci_fixups_enable) = .;            \
 189                 VMLINUX_SYMBOL(__start_pci_fixups_resume) = .;          \
 190 -               *(.pci_fixup_resume)                                    \
 191 +               KEEP(*(.pci_fixup_resume))                              \
 192                 VMLINUX_SYMBOL(__end_pci_fixups_resume) = .;            \
 193                 VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .;    \
 194 -               *(.pci_fixup_resume_early)                              \
 195 +               KEEP(*(.pci_fixup_resume_early))                        \
 196                 VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .;      \
 197                 VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .;         \
 198 -               *(.pci_fixup_suspend)                                   \
 199 +               KEEP(*(.pci_fixup_suspend))                             \
 200                 VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .;           \
 201         }                                                               \
 202                                                                         \
 203         /* Built-in firmware blobs */                                   \
 204         .builtin_fw        : AT(ADDR(.builtin_fw) - LOAD_OFFSET) {      \
 205                 VMLINUX_SYMBOL(__start_builtin_fw) = .;                 \
 206 -               *(.builtin_fw)                                          \
 207 +               KEEP(*(.builtin_fw))                                    \
 208                 VMLINUX_SYMBOL(__end_builtin_fw) = .;                   \
 209         }                                                               \
 210                                                                         \
 211 @@ -283,49 +284,49 @@
 212         /* Kernel symbol table: Normal symbols */                       \
 213         __ksymtab         : AT(ADDR(__ksymtab) - LOAD_OFFSET) {         \
 214                 VMLINUX_SYMBOL(__start___ksymtab) = .;                  \
 215 -               *(SORT(___ksymtab+*))                                   \
 216 +               KEEP(*(SORT(___ksymtab+*)))                             \
 217                 VMLINUX_SYMBOL(__stop___ksymtab) = .;                   \
 218         }                                                               \
 219                                                                         \
 220         /* Kernel symbol table: GPL-only symbols */                     \
 221         __ksymtab_gpl     : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) {     \
 222                 VMLINUX_SYMBOL(__start___ksymtab_gpl) = .;              \
 223 -               *(SORT(___ksymtab_gpl+*))                               \
 224 +               KEEP(*(SORT(___ksymtab_gpl+*)))                         \
 225                 VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .;               \
 226         }                                                               \
 227                                                                         \
 228         /* Kernel symbol table: Normal unused symbols */                \
 229         __ksymtab_unused  : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) {  \
 230                 VMLINUX_SYMBOL(__start___ksymtab_unused) = .;           \
 231 -               *(SORT(___ksymtab_unused+*))                            \
 232 +               KEEP(*(SORT(___ksymtab_unused+*)))                      \
 233                 VMLINUX_SYMBOL(__stop___ksymtab_unused) = .;            \
 234         }                                                               \
 235                                                                         \
 236         /* Kernel symbol table: GPL-only unused symbols */              \
 237         __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \
 238                 VMLINUX_SYMBOL(__start___ksymtab_unused_gpl) = .;       \
 239 -               *(SORT(___ksymtab_unused_gpl+*))                        \
 240 +               KEEP(*(SORT(___ksymtab_unused_gpl+*)))                  \
 241                 VMLINUX_SYMBOL(__stop___ksymtab_unused_gpl) = .;        \
 242         }                                                               \
 243                                                                         \
 244         /* Kernel symbol table: GPL-future-only symbols */              \
 245         __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \
 246                 VMLINUX_SYMBOL(__start___ksymtab_gpl_future) = .;       \
 247 -               *(SORT(___ksymtab_gpl_future+*))                        \
 248 +               KEEP(*(SORT(___ksymtab_gpl_future+*)))                  \
 249                 VMLINUX_SYMBOL(__stop___ksymtab_gpl_future) = .;        \
 250         }                                                               \
 251                                                                         \
 252         /* Kernel symbol table: Normal symbols */                       \
 253         __kcrctab         : AT(ADDR(__kcrctab) - LOAD_OFFSET) {         \
 254                 VMLINUX_SYMBOL(__start___kcrctab) = .;                  \
 255 -               *(SORT(___kcrctab+*))                                   \
 256 +               KEEP(*(SORT(___kcrctab+*)))                             \
 257                 VMLINUX_SYMBOL(__stop___kcrctab) = .;                   \
 258         }                                                               \
 259                                                                         \
 260         /* Kernel symbol table: GPL-only symbols */                     \
 261         __kcrctab_gpl     : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) {     \
 262                 VMLINUX_SYMBOL(__start___kcrctab_gpl) = .;              \
 263 -               *(SORT(___kcrctab_gpl+*))                               \
 264 +               KEEP(*(SORT(___kcrctab_gpl+*)))                         \
 265                 VMLINUX_SYMBOL(__stop___kcrctab_gpl) = .;               \
 266         }                                                               \
 267                                                                         \
 268 @@ -339,14 +340,14 @@
 269         /* Kernel symbol table: GPL-only unused symbols */              \
 270         __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \
 271                 VMLINUX_SYMBOL(__start___kcrctab_unused_gpl) = .;       \
 272 -               *(SORT(___kcrctab_unused_gpl+*))                        \
 273 +               KEEP(*(SORT(___kcrctab_unused_gpl+*)))                  \
 274                 VMLINUX_SYMBOL(__stop___kcrctab_unused_gpl) = .;        \
 275         }                                                               \
 276                                                                         \
 277         /* Kernel symbol table: GPL-future-only symbols */              \
 278         __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \
 279                 VMLINUX_SYMBOL(__start___kcrctab_gpl_future) = .;       \
 280 -               *(SORT(___kcrctab_gpl_future+*))                        \
 281 +               KEEP(*(SORT(___kcrctab_gpl_future+*)))                  \
 282                 VMLINUX_SYMBOL(__stop___kcrctab_gpl_future) = .;        \
 283         }                                                               \
 284                                                                         \
 285 @@ -365,14 +366,14 @@
 286         /* Built-in module parameters. */                               \
 287         __param : AT(ADDR(__param) - LOAD_OFFSET) {                     \
 288                 VMLINUX_SYMBOL(__start___param) = .;                    \
 289 -               *(__param)                                              \
 290 +               KEEP(*(__param))                                        \
 291                 VMLINUX_SYMBOL(__stop___param) = .;                     \
 292         }                                                               \
 293                                                                         \
 294         /* Built-in module versions. */                                 \
 295         __modver : AT(ADDR(__modver) - LOAD_OFFSET) {                   \
 296                 VMLINUX_SYMBOL(__start___modver) = .;                   \
 297 -               *(__modver)                                             \
 298 +               KEEP(*(__modver))                                       \
 299                 VMLINUX_SYMBOL(__stop___modver) = .;                    \
 300                 . = ALIGN((align));                                     \
 301                 VMLINUX_SYMBOL(__end_rodata) = .;                       \
 302 @@ -428,7 +429,7 @@
 303  #define ENTRY_TEXT                                                     \
 304                 ALIGN_FUNCTION();                                       \
 305                 VMLINUX_SYMBOL(__entry_text_start) = .;                 \
 306 -               *(.entry.text)                                          \
 307 +               KEEP(*(.entry.text))                                    \
 308                 VMLINUX_SYMBOL(__entry_text_end) = .;
 309
 310  #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 311 @@ -456,7 +457,7 @@
 312         . = ALIGN(align);                                               \
 313         __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {               \
 314                 VMLINUX_SYMBOL(__start___ex_table) = .;                 \
 315 -               *(__ex_table)                                           \
 316 +               KEEP(*(__ex_table))                                             \
 317                 VMLINUX_SYMBOL(__stop___ex_table) = .;                  \
 318         }
 319
 320 @@ -472,8 +473,8 @@
 321  #ifdef CONFIG_CONSTRUCTORS
 322  #define KERNEL_CTORS() . = ALIGN(8);                      \
 323                         VMLINUX_SYMBOL(__ctors_start) = .; \
 324 -                       *(.ctors)                          \
 325 -                       *(.init_array)                     \
 326 +                       KEEP(*(.ctors))                    \
 327 +                       KEEP(*(.init_array))               \
 328                         VMLINUX_SYMBOL(__ctors_end) = .;
 329  #else
 330  #define KERNEL_CTORS()
 331 @@ -517,7 +518,7 @@
 332  #define SBSS(sbss_align)                                               \
 333         . = ALIGN(sbss_align);                                          \
 334         .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) {                         \
 335 -               *(.sbss)                                                \
 336 +               *(.sbss .sbss.*)                                        \
 337                 *(.scommon)                                             \
 338         }
 339
 340 @@ -535,7 +536,7 @@
 341                 BSS_FIRST_SECTIONS                                      \
 342                 *(.bss..page_aligned)                                   \
 343                 *(.dynbss)                                              \
 344 -               *(.bss)                                                 \
 345 +               *(.bss .bss.*)                                          \
 346                 *(COMMON)                                               \
 347         }
 348
 349 @@ -596,7 +597,7 @@
 350         . = ALIGN(4);                                                   \
 351         .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) {               \
 352                 VMLINUX_SYMBOL(__tracedata_start) = .;                  \
 353 -               *(.tracedata)                                           \
 354 +               KEEP(*(.tracedata))                                     \
 355                 VMLINUX_SYMBOL(__tracedata_end) = .;                    \
 356         }
 357  #else
 358 @@ -613,17 +614,17 @@
 359  #define INIT_SETUP(initsetup_align)                                    \
 360                 . = ALIGN(initsetup_align);                             \
 361                 VMLINUX_SYMBOL(__setup_start) = .;                      \
 362 -               *(.init.setup)                                          \
 363 +               KEEP(*(.init.setup))                                    \
 364                 VMLINUX_SYMBOL(__setup_end) = .;
 365
 366  #define INIT_CALLS_LEVEL(level)                                                \
 367                 VMLINUX_SYMBOL(__initcall##level##_start) = .;          \
 368 -               *(.initcall##level##.init)                              \
 369 -               *(.initcall##level##s.init)                             \
 370 +               KEEP(*(.initcall##level##.init))                        \
 371 +               KEEP(*(.initcall##level##s.init))                       \
 372
 373  #define INIT_CALLS                                                     \
 374                 VMLINUX_SYMBOL(__initcall_start) = .;                   \
 375 -               *(.initcallearly.init)                                  \
 376 +               KEEP(*(.initcallearly.init))                            \
 377                 INIT_CALLS_LEVEL(0)                                     \
 378                 INIT_CALLS_LEVEL(1)                                     \
 379                 INIT_CALLS_LEVEL(2)                                     \
 380 @@ -637,21 +638,21 @@
 381
 382  #define CON_INITCALL                                                   \
 383                 VMLINUX_SYMBOL(__con_initcall_start) = .;               \
 384 -               *(.con_initcall.init)                                   \
 385 +               KEEP(*(.con_initcall.init))                             \
 386                 VMLINUX_SYMBOL(__con_initcall_end) = .;
 387
 388  #define SECURITY_INITCALL                                              \
 389                 VMLINUX_SYMBOL(__security_initcall_start) = .;          \
 390 -               *(.security_initcall.init)                              \
 391 +               KEEP(*(.security_initcall.init))                        \
 392                 VMLINUX_SYMBOL(__security_initcall_end) = .;
 393
 394  #ifdef CONFIG_BLK_DEV_INITRD
 395  #define INIT_RAM_FS                                                    \
 396         . = ALIGN(4);                                                   \
 397         VMLINUX_SYMBOL(__initramfs_start) = .;                          \
 398 -       *(.init.ramfs)                                                  \
 399 +       KEEP(*(.init.ramfs))                                            \
 400         . = ALIGN(8);                                                   \
 401 -       *(.init.ramfs.info)
 402 +       KEEP(*(.init.ramfs.info))
 403  #else
 404  #define INIT_RAM_FS
 405  #endif
 406 --- a/arch/arm/Makefile
 407 +++ b/arch/arm/Makefile
 408 @@ -18,11 +18,16 @@ ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
 409  LDFLAGS_vmlinux        += --be8
 410  LDFLAGS_MODULE += --be8
 411  endif
 412 +LDFLAGS_vmlinux += --gc-sections
 413
 414  OBJCOPYFLAGS   :=-O binary -R .comment -S
 415  GZFLAGS                :=-9
 416  #KBUILD_CFLAGS +=-pipe
 417
 418 +ifndef CONFIG_FUNCTION_TRACER
 419 +KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 420 +endif
 421 +
 422  # Never generate .eh_frame
 423  KBUILD_CFLAGS  += $(call cc-option,-fno-dwarf2-cfi-asm)
 424
 425 --- a/arch/arm/kernel/vmlinux.lds.S
 426 +++ b/arch/arm/kernel/vmlinux.lds.S
 427 @@ -12,13 +12,13 @@
 428  #define PROC_INFO                                                      \
 429         . = ALIGN(4);                                                   \
 430         VMLINUX_SYMBOL(__proc_info_begin) = .;                          \
 431 -       *(.proc.info.init)                                              \
 432 +       KEEP(*(.proc.info.init))                                        \
 433         VMLINUX_SYMBOL(__proc_info_end) = .;
 434
 435  #define IDMAP_TEXT                                                     \
 436         ALIGN_FUNCTION();                                               \
 437         VMLINUX_SYMBOL(__idmap_text_start) = .;                         \
 438 -       *(.idmap.text)                                                  \
 439 +       KEEP(*(.idmap.text))                                            \
 440         VMLINUX_SYMBOL(__idmap_text_end) = .;                           \
 441         . = ALIGN(32);                                                  \
 442         VMLINUX_SYMBOL(__hyp_idmap_text_start) = .;                     \
 443 @@ -93,7 +93,7 @@ SECTIONS
 444         .text : {                       /* Real text segment            */
 445                 _stext = .;             /* Text and read-only data      */
 446                         __exception_text_start = .;
 447 -                       *(.exception.text)
 448 +                       KEEP(*(.exception.text))
 449                         __exception_text_end = .;
 450                         IRQENTRY_TEXT
 451                         TEXT_TEXT
 452 @@ -118,7 +118,7 @@ SECTIONS
 453         __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
 454                 __start___ex_table = .;
 455  #ifdef CONFIG_MMU
 456 -               *(__ex_table)
 457 +               KEEP(*(__ex_table))
 458  #endif
 459                 __stop___ex_table = .;
 460         }
 461 @@ -130,12 +130,12 @@ SECTIONS
 462         . = ALIGN(8);
 463         .ARM.unwind_idx : {
 464                 __start_unwind_idx = .;
 465 -               *(.ARM.exidx*)
 466 +               KEEP(*(.ARM.exidx*))
 467                 __stop_unwind_idx = .;
 468         }
 469         .ARM.unwind_tab : {
 470                 __start_unwind_tab = .;
 471 -               *(.ARM.extab*)
 472 +               KEEP(*(.ARM.extab*))
 473                 __stop_unwind_tab = .;
 474         }
 475  #endif
 476 @@ -154,14 +154,14 @@ SECTIONS
 477          */
 478         __vectors_start = .;
 479         .vectors 0 : AT(__vectors_start) {
 480 -               *(.vectors)
 481 +               KEEP(*(.vectors))
 482         }
 483         . = __vectors_start + SIZEOF(.vectors);
 484         __vectors_end = .;
 485
 486         __stubs_start = .;
 487         .stubs 0x1000 : AT(__stubs_start) {
 488 -               *(.stubs)
 489 +               KEEP(*(.stubs))
 490         }
 491         . = __stubs_start + SIZEOF(.stubs);
 492         __stubs_end = .;
 493 @@ -175,24 +175,24 @@ SECTIONS
 494         }
 495         .init.arch.info : {
 496                 __arch_info_begin = .;
 497 -               *(.arch.info.init)
 498 +               KEEP(*(.arch.info.init))
 499                 __arch_info_end = .;
 500         }
 501         .init.tagtable : {
 502                 __tagtable_begin = .;
 503 -               *(.taglist.init)
 504 +               KEEP(*(.taglist.init))
 505                 __tagtable_end = .;
 506         }
 507  #ifdef CONFIG_SMP_ON_UP
 508         .init.smpalt : {
 509                 __smpalt_begin = .;
 510 -               *(.alt.smp.init)
 511 +               KEEP(*(.alt.smp.init))
 512                 __smpalt_end = .;
 513         }
 514  #endif
 515         .init.pv_table : {
 516                 __pv_table_begin = .;
 517 -               *(.pv_table)
 518 +               KEEP(*(.pv_table))
 519                 __pv_table_end = .;
 520         }
 521         .init.data : {
 522 --- a/arch/arm/boot/compressed/Makefile
 523 +++ b/arch/arm/boot/compressed/Makefile
 524 @@ -120,6 +120,7 @@ ifeq ($(CONFIG_FUNCTION_TRACER),y)
 525  ORIG_CFLAGS := $(KBUILD_CFLAGS)
 526  KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
 527  endif
 528 +KBUILD_CFLAGS_KERNEL := $(patsubst -f%-sections,,$(KBUILD_CFLAGS_KERNEL))
 529
 530  ccflags-y := -fpic -mno-single-pic-base -fno-builtin -I$(obj)
 531  asflags-y := -DZIMAGE