target/linux/generic/patches-3.18/220-gc_sections.patch

   1 From: Felix Fietkau <nbd@openwrt.org>
   2
   3 use -ffunction-sections, -fdata-sections and --gc-sections --sort-section=name
   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 --sort-section=name
  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  #
  29  # pass -msoft-float to GAS if it supports it.  However on newer binutils
  30  # (specifically newer than 2.24.51.20140728) we then also need to explicitly
  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 @@ -89,7 +89,7 @@
  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 @@ -97,7 +97,7 @@
  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 @@ -105,7 +105,7 @@
  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 @@ -123,7 +123,7 @@
  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 @@ -131,7 +131,7 @@
  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 @@ -144,7 +144,7 @@
  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 @@ -158,8 +158,8 @@
 108  #define _OF_TABLE_1(name)                                              \
 109         . = ALIGN(8);                                                   \
 110         VMLINUX_SYMBOL(__##name##_of_table) = .;                        \
 111 -       *(__##name##_of_table)                                          \
 112 -       *(__##name##_of_table_end)
 113 +       KEEP(*(__##name##_of_table))                                    \
 114 +       KEEP(*(__##name##_of_table_end))
 115
 116  #define CLKSRC_OF_TABLES()     OF_TABLE(CONFIG_CLKSRC_OF, clksrc)
 117  #define IRQCHIP_OF_MATCH_TABLE() OF_TABLE(CONFIG_IRQCHIP, irqchip)
 118 @@ -171,7 +171,7 @@
 119  #define KERNEL_DTB()                                                   \
 120         STRUCT_ALIGN();                                                 \
 121         VMLINUX_SYMBOL(__dtb_start) = .;                                \
 122 -       *(.dtb.init.rodata)                                             \
 123 +       KEEP(*(.dtb.init.rodata))                                       \
 124         VMLINUX_SYMBOL(__dtb_end) = .;
 125
 126  /* .data section */
 127 @@ -187,16 +187,17 @@
 128         /* implement dynamic printk debug */                            \
 129         . = ALIGN(8);                                                   \
 130         VMLINUX_SYMBOL(__start___jump_table) = .;                       \
 131 -       *(__jump_table)                                                 \
 132 +       KEEP(*(__jump_table))                                           \
 133         VMLINUX_SYMBOL(__stop___jump_table) = .;                        \
 134         . = ALIGN(8);                                                   \
 135         VMLINUX_SYMBOL(__start___verbose) = .;                          \
 136 -       *(__verbose)                                                    \
 137 +       KEEP(*(__verbose))                                              \
 138         VMLINUX_SYMBOL(__stop___verbose) = .;                           \
 139         LIKELY_PROFILE()                                                \
 140         BRANCH_PROFILE()                                                \
 141         TRACE_PRINTKS()                                                 \
 142 -       TRACEPOINT_STR()
 143 +       TRACEPOINT_STR()                                                \
 144 +       *(.data.[a-zA-Z_]*)
 145
 146  /*
 147   * Data section helpers
 148 @@ -250,35 +251,35 @@
 149         /* PCI quirks */                                                \
 150         .pci_fixup        : AT(ADDR(.pci_fixup) - LOAD_OFFSET) {        \
 151                 VMLINUX_SYMBOL(__start_pci_fixups_early) = .;           \
 152 -               *(.pci_fixup_early)                                     \
 153 +               KEEP(*(.pci_fixup_early))                               \
 154                 VMLINUX_SYMBOL(__end_pci_fixups_early) = .;             \
 155                 VMLINUX_SYMBOL(__start_pci_fixups_header) = .;          \
 156 -               *(.pci_fixup_header)                                    \
 157 +               KEEP(*(.pci_fixup_header))                              \
 158                 VMLINUX_SYMBOL(__end_pci_fixups_header) = .;            \
 159                 VMLINUX_SYMBOL(__start_pci_fixups_final) = .;           \
 160 -               *(.pci_fixup_final)                                     \
 161 +               KEEP(*(.pci_fixup_final))                               \
 162                 VMLINUX_SYMBOL(__end_pci_fixups_final) = .;             \
 163                 VMLINUX_SYMBOL(__start_pci_fixups_enable) = .;          \
 164 -               *(.pci_fixup_enable)                                    \
 165 +               KEEP(*(.pci_fixup_enable))                              \
 166                 VMLINUX_SYMBOL(__end_pci_fixups_enable) = .;            \
 167                 VMLINUX_SYMBOL(__start_pci_fixups_resume) = .;          \
 168 -               *(.pci_fixup_resume)                                    \
 169 +               KEEP(*(.pci_fixup_resume))                              \
 170                 VMLINUX_SYMBOL(__end_pci_fixups_resume) = .;            \
 171                 VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .;    \
 172 -               *(.pci_fixup_resume_early)                              \
 173 +               KEEP(*(.pci_fixup_resume_early))                        \
 174                 VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .;      \
 175                 VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .;         \
 176 -               *(.pci_fixup_suspend)                                   \
 177 +               KEEP(*(.pci_fixup_suspend))                             \
 178                 VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .;           \
 179                 VMLINUX_SYMBOL(__start_pci_fixups_suspend_late) = .;    \
 180 -               *(.pci_fixup_suspend_late)                              \
 181 +               KEEP(*(.pci_fixup_suspend_late))                        \
 182                 VMLINUX_SYMBOL(__end_pci_fixups_suspend_late) = .;      \
 183         }                                                               \
 184                                                                         \
 185         /* Built-in firmware blobs */                                   \
 186         .builtin_fw        : AT(ADDR(.builtin_fw) - LOAD_OFFSET) {      \
 187                 VMLINUX_SYMBOL(__start_builtin_fw) = .;                 \
 188 -               *(.builtin_fw)                                          \
 189 +               KEEP(*(.builtin_fw))                                    \
 190                 VMLINUX_SYMBOL(__end_builtin_fw) = .;                   \
 191         }                                                               \
 192                                                                         \
 193 @@ -287,49 +288,49 @@
 194         /* Kernel symbol table: Normal symbols */                       \
 195         __ksymtab         : AT(ADDR(__ksymtab) - LOAD_OFFSET) {         \
 196                 VMLINUX_SYMBOL(__start___ksymtab) = .;                  \
 197 -               *(SORT(___ksymtab+*))                                   \
 198 +               KEEP(*(SORT(___ksymtab+*)))                             \
 199                 VMLINUX_SYMBOL(__stop___ksymtab) = .;                   \
 200         }                                                               \
 201                                                                         \
 202         /* Kernel symbol table: GPL-only symbols */                     \
 203         __ksymtab_gpl     : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) {     \
 204                 VMLINUX_SYMBOL(__start___ksymtab_gpl) = .;              \
 205 -               *(SORT(___ksymtab_gpl+*))                               \
 206 +               KEEP(*(SORT(___ksymtab_gpl+*)))                         \
 207                 VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .;               \
 208         }                                                               \
 209                                                                         \
 210         /* Kernel symbol table: Normal unused symbols */                \
 211         __ksymtab_unused  : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) {  \
 212                 VMLINUX_SYMBOL(__start___ksymtab_unused) = .;           \
 213 -               *(SORT(___ksymtab_unused+*))                            \
 214 +               KEEP(*(SORT(___ksymtab_unused+*)))                      \
 215                 VMLINUX_SYMBOL(__stop___ksymtab_unused) = .;            \
 216         }                                                               \
 217                                                                         \
 218         /* Kernel symbol table: GPL-only unused symbols */              \
 219         __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \
 220                 VMLINUX_SYMBOL(__start___ksymtab_unused_gpl) = .;       \
 221 -               *(SORT(___ksymtab_unused_gpl+*))                        \
 222 +               KEEP(*(SORT(___ksymtab_unused_gpl+*)))                  \
 223                 VMLINUX_SYMBOL(__stop___ksymtab_unused_gpl) = .;        \
 224         }                                                               \
 225                                                                         \
 226         /* Kernel symbol table: GPL-future-only symbols */              \
 227         __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \
 228                 VMLINUX_SYMBOL(__start___ksymtab_gpl_future) = .;       \
 229 -               *(SORT(___ksymtab_gpl_future+*))                        \
 230 +               KEEP(*(SORT(___ksymtab_gpl_future+*)))                  \
 231                 VMLINUX_SYMBOL(__stop___ksymtab_gpl_future) = .;        \
 232         }                                                               \
 233                                                                         \
 234         /* Kernel symbol table: Normal symbols */                       \
 235         __kcrctab         : AT(ADDR(__kcrctab) - LOAD_OFFSET) {         \
 236                 VMLINUX_SYMBOL(__start___kcrctab) = .;                  \
 237 -               *(SORT(___kcrctab+*))                                   \
 238 +               KEEP(*(SORT(___kcrctab+*)))                             \
 239                 VMLINUX_SYMBOL(__stop___kcrctab) = .;                   \
 240         }                                                               \
 241                                                                         \
 242         /* Kernel symbol table: GPL-only symbols */                     \
 243         __kcrctab_gpl     : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) {     \
 244                 VMLINUX_SYMBOL(__start___kcrctab_gpl) = .;              \
 245 -               *(SORT(___kcrctab_gpl+*))                               \
 246 +               KEEP(*(SORT(___kcrctab_gpl+*)))                         \
 247                 VMLINUX_SYMBOL(__stop___kcrctab_gpl) = .;               \
 248         }                                                               \
 249                                                                         \
 250 @@ -343,14 +344,14 @@
 251         /* Kernel symbol table: GPL-only unused symbols */              \
 252         __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \
 253                 VMLINUX_SYMBOL(__start___kcrctab_unused_gpl) = .;       \
 254 -               *(SORT(___kcrctab_unused_gpl+*))                        \
 255 +               KEEP(*(SORT(___kcrctab_unused_gpl+*)))                  \
 256                 VMLINUX_SYMBOL(__stop___kcrctab_unused_gpl) = .;        \
 257         }                                                               \
 258                                                                         \
 259         /* Kernel symbol table: GPL-future-only symbols */              \
 260         __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \
 261                 VMLINUX_SYMBOL(__start___kcrctab_gpl_future) = .;       \
 262 -               *(SORT(___kcrctab_gpl_future+*))                        \
 263 +               KEEP(*(SORT(___kcrctab_gpl_future+*)))                  \
 264                 VMLINUX_SYMBOL(__stop___kcrctab_gpl_future) = .;        \
 265         }                                                               \
 266                                                                         \
 267 @@ -369,14 +370,14 @@
 268         /* Built-in module parameters. */                               \
 269         __param : AT(ADDR(__param) - LOAD_OFFSET) {                     \
 270                 VMLINUX_SYMBOL(__start___param) = .;                    \
 271 -               *(__param)                                              \
 272 +               KEEP(*(__param))                                        \
 273                 VMLINUX_SYMBOL(__stop___param) = .;                     \
 274         }                                                               \
 275                                                                         \
 276         /* Built-in module versions. */                                 \
 277         __modver : AT(ADDR(__modver) - LOAD_OFFSET) {                   \
 278                 VMLINUX_SYMBOL(__start___modver) = .;                   \
 279 -               *(__modver)                                             \
 280 +               KEEP(*(__modver))                                       \
 281                 VMLINUX_SYMBOL(__stop___modver) = .;                    \
 282                 . = ALIGN((align));                                     \
 283                 VMLINUX_SYMBOL(__end_rodata) = .;                       \
 284 @@ -432,7 +433,7 @@
 285  #define ENTRY_TEXT                                                     \
 286                 ALIGN_FUNCTION();                                       \
 287                 VMLINUX_SYMBOL(__entry_text_start) = .;                 \
 288 -               *(.entry.text)                                          \
 289 +               KEEP(*(.entry.text))                                    \
 290                 VMLINUX_SYMBOL(__entry_text_end) = .;
 291
 292  #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 293 @@ -460,7 +461,7 @@
 294         . = ALIGN(align);                                               \
 295         __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {               \
 296                 VMLINUX_SYMBOL(__start___ex_table) = .;                 \
 297 -               *(__ex_table)                                           \
 298 +               KEEP(*(__ex_table))                                             \
 299                 VMLINUX_SYMBOL(__stop___ex_table) = .;                  \
 300         }
 301
 302 @@ -476,8 +477,8 @@
 303  #ifdef CONFIG_CONSTRUCTORS
 304  #define KERNEL_CTORS() . = ALIGN(8);                      \
 305                         VMLINUX_SYMBOL(__ctors_start) = .; \
 306 -                       *(.ctors)                          \
 307 -                       *(.init_array)                     \
 308 +                       KEEP(*(.ctors))                    \
 309 +                       KEEP(*(.init_array))               \
 310                         VMLINUX_SYMBOL(__ctors_end) = .;
 311  #else
 312  #define KERNEL_CTORS()
 313 @@ -525,7 +526,7 @@
 314  #define SBSS(sbss_align)                                               \
 315         . = ALIGN(sbss_align);                                          \
 316         .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) {                         \
 317 -               *(.sbss)                                                \
 318 +               *(.sbss .sbss.*)                                        \
 319                 *(.scommon)                                             \
 320         }
 321
 322 @@ -543,7 +544,7 @@
 323                 BSS_FIRST_SECTIONS                                      \
 324                 *(.bss..page_aligned)                                   \
 325                 *(.dynbss)                                              \
 326 -               *(.bss)                                                 \
 327 +               *(.bss .bss.*)                                          \
 328                 *(COMMON)                                               \
 329         }
 330
 331 @@ -604,7 +605,7 @@
 332         . = ALIGN(4);                                                   \
 333         .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) {               \
 334                 VMLINUX_SYMBOL(__tracedata_start) = .;                  \
 335 -               *(.tracedata)                                           \
 336 +               KEEP(*(.tracedata))                                     \
 337                 VMLINUX_SYMBOL(__tracedata_end) = .;                    \
 338         }
 339  #else
 340 @@ -621,17 +622,17 @@
 341  #define INIT_SETUP(initsetup_align)                                    \
 342                 . = ALIGN(initsetup_align);                             \
 343                 VMLINUX_SYMBOL(__setup_start) = .;                      \
 344 -               *(.init.setup)                                          \
 345 +               KEEP(*(.init.setup))                                    \
 346                 VMLINUX_SYMBOL(__setup_end) = .;
 347
 348  #define INIT_CALLS_LEVEL(level)                                                \
 349                 VMLINUX_SYMBOL(__initcall##level##_start) = .;          \
 350 -               *(.initcall##level##.init)                              \
 351 -               *(.initcall##level##s.init)                             \
 352 +               KEEP(*(.initcall##level##.init))                        \
 353 +               KEEP(*(.initcall##level##s.init))                       \
 354
 355  #define INIT_CALLS                                                     \
 356                 VMLINUX_SYMBOL(__initcall_start) = .;                   \
 357 -               *(.initcallearly.init)                                  \
 358 +               KEEP(*(.initcallearly.init))                            \
 359                 INIT_CALLS_LEVEL(0)                                     \
 360                 INIT_CALLS_LEVEL(1)                                     \
 361                 INIT_CALLS_LEVEL(2)                                     \
 362 @@ -645,21 +646,21 @@
 363
 364  #define CON_INITCALL                                                   \
 365                 VMLINUX_SYMBOL(__con_initcall_start) = .;               \
 366 -               *(.con_initcall.init)                                   \
 367 +               KEEP(*(.con_initcall.init))                             \
 368                 VMLINUX_SYMBOL(__con_initcall_end) = .;
 369
 370  #define SECURITY_INITCALL                                              \
 371                 VMLINUX_SYMBOL(__security_initcall_start) = .;          \
 372 -               *(.security_initcall.init)                              \
 373 +               KEEP(*(.security_initcall.init))                        \
 374                 VMLINUX_SYMBOL(__security_initcall_end) = .;
 375
 376  #ifdef CONFIG_BLK_DEV_INITRD
 377  #define INIT_RAM_FS                                                    \
 378         . = ALIGN(4);                                                   \
 379         VMLINUX_SYMBOL(__initramfs_start) = .;                          \
 380 -       *(.init.ramfs)                                                  \
 381 +       KEEP(*(.init.ramfs))                                            \
 382         . = ALIGN(8);                                                   \
 383 -       *(.init.ramfs.info)
 384 +       KEEP(*(.init.ramfs.info))
 385  #else
 386  #define INIT_RAM_FS
 387  #endif
 388 --- a/arch/arm/Makefile
 389 +++ b/arch/arm/Makefile
 390 @@ -18,11 +18,16 @@ ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
 391  LDFLAGS_vmlinux        += --be8
 392  LDFLAGS_MODULE += --be8
 393  endif
 394 +LDFLAGS_vmlinux += --gc-sections --sort-section=name
 395
 396  OBJCOPYFLAGS   :=-O binary -R .comment -S
 397  GZFLAGS                :=-9
 398  #KBUILD_CFLAGS +=-pipe
 399
 400 +ifndef CONFIG_FUNCTION_TRACER
 401 +KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 402 +endif
 403 +
 404  # Never generate .eh_frame
 405  KBUILD_CFLAGS  += $(call cc-option,-fno-dwarf2-cfi-asm)
 406
 407 --- a/arch/arm/kernel/vmlinux.lds.S
 408 +++ b/arch/arm/kernel/vmlinux.lds.S
 409 @@ -12,13 +12,13 @@
 410  #define PROC_INFO                                                      \
 411         . = ALIGN(4);                                                   \
 412         VMLINUX_SYMBOL(__proc_info_begin) = .;                          \
 413 -       *(.proc.info.init)                                              \
 414 +       KEEP(*(.proc.info.init))                                        \
 415         VMLINUX_SYMBOL(__proc_info_end) = .;
 416
 417  #define IDMAP_TEXT                                                     \
 418         ALIGN_FUNCTION();                                               \
 419         VMLINUX_SYMBOL(__idmap_text_start) = .;                         \
 420 -       *(.idmap.text)                                                  \
 421 +       KEEP(*(.idmap.text))                                            \
 422         VMLINUX_SYMBOL(__idmap_text_end) = .;                           \
 423         . = ALIGN(32);                                                  \
 424         VMLINUX_SYMBOL(__hyp_idmap_text_start) = .;                     \
 425 @@ -93,7 +93,7 @@ SECTIONS
 426         .text : {                       /* Real text segment            */
 427                 _stext = .;             /* Text and read-only data      */
 428                         __exception_text_start = .;
 429 -                       *(.exception.text)
 430 +                       KEEP(*(.exception.text))
 431                         __exception_text_end = .;
 432                         IRQENTRY_TEXT
 433                         TEXT_TEXT
 434 @@ -118,7 +118,7 @@ SECTIONS
 435         __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
 436                 __start___ex_table = .;
 437  #ifdef CONFIG_MMU
 438 -               *(__ex_table)
 439 +               KEEP(*(__ex_table))
 440  #endif
 441                 __stop___ex_table = .;
 442         }
 443 @@ -130,12 +130,12 @@ SECTIONS
 444         . = ALIGN(8);
 445         .ARM.unwind_idx : {
 446                 __start_unwind_idx = .;
 447 -               *(.ARM.exidx*)
 448 +               KEEP(*(.ARM.exidx*))
 449                 __stop_unwind_idx = .;
 450         }
 451         .ARM.unwind_tab : {
 452                 __start_unwind_tab = .;
 453 -               *(.ARM.extab*)
 454 +               KEEP(*(.ARM.extab*))
 455                 __stop_unwind_tab = .;
 456         }
 457  #endif
 458 @@ -154,14 +154,14 @@ SECTIONS
 459          */
 460         __vectors_start = .;
 461         .vectors 0 : AT(__vectors_start) {
 462 -               *(.vectors)
 463 +               KEEP(*(.vectors))
 464         }
 465         . = __vectors_start + SIZEOF(.vectors);
 466         __vectors_end = .;
 467
 468         __stubs_start = .;
 469         .stubs 0x1000 : AT(__stubs_start) {
 470 -               *(.stubs)
 471 +               KEEP(*(.stubs))
 472         }
 473         . = __stubs_start + SIZEOF(.stubs);
 474         __stubs_end = .;
 475 @@ -175,24 +175,24 @@ SECTIONS
 476         }
 477         .init.arch.info : {
 478                 __arch_info_begin = .;
 479 -               *(.arch.info.init)
 480 +               KEEP(*(.arch.info.init))
 481                 __arch_info_end = .;
 482         }
 483         .init.tagtable : {
 484                 __tagtable_begin = .;
 485 -               *(.taglist.init)
 486 +               KEEP(*(.taglist.init))
 487                 __tagtable_end = .;
 488         }
 489  #ifdef CONFIG_SMP_ON_UP
 490         .init.smpalt : {
 491                 __smpalt_begin = .;
 492 -               *(.alt.smp.init)
 493 +               KEEP(*(.alt.smp.init))
 494                 __smpalt_end = .;
 495         }
 496  #endif
 497         .init.pv_table : {
 498                 __pv_table_begin = .;
 499 -               *(.pv_table)
 500 +               KEEP(*(.pv_table))
 501                 __pv_table_end = .;
 502         }
 503         .init.data : {
 504 --- a/arch/arm/boot/compressed/Makefile
 505 +++ b/arch/arm/boot/compressed/Makefile
 506 @@ -122,6 +122,7 @@ ifeq ($(CONFIG_FUNCTION_TRACER),y)
 507  ORIG_CFLAGS := $(KBUILD_CFLAGS)
 508  KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
 509  endif
 510 +KBUILD_CFLAGS_KERNEL := $(patsubst -f%-sections,,$(KBUILD_CFLAGS_KERNEL))
 511
 512  ccflags-y := -fpic -mno-single-pic-base -fno-builtin -I$(obj)
 513  asflags-y := -DZIMAGE