powerpc: Link warning for orphan sections
authorNicholas Piggin <npiggin@gmail.com>
Thu, 11 May 2017 17:40:40 +0000 (03:40 +1000)
committerMichael Ellerman <mpe@ellerman.id.au>
Tue, 30 May 2017 04:59:51 +0000 (14:59 +1000)
Add --orphan-handling=warn to final link flags. This ensures we can
handle all sections explicitly. This would have caught subtle breakage
such as 7de3b27bac47da9de08409df1d69664acbb72197 at build-time.

Also bring existing orphan sections into the fold:
- .text.hot and .text.unlikely are compiler generated sections.
- .sdata2, .dynsbss, .plt are used by PPC32
- We previously did not specify DWARF_DEBUG or STABS_DEBUG
- DWARF_DEBUG did not include all DWARF sections that can be emitted
- A number of sections are unused and can be discarded.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/Makefile
arch/powerpc/kernel/vmlinux.lds.S
include/asm-generic/vmlinux.lds.h

index eaa1865e4a8d6b860ef082a2650ad20f469b40cc..8d4ed73d549091368be87c5b4483f33d6b00640d 100644 (file)
@@ -98,6 +98,7 @@ endif
 LDFLAGS_vmlinux-y := -Bstatic
 LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) := -pie
 LDFLAGS_vmlinux        := $(LDFLAGS_vmlinux-y)
+LDFLAGS_vmlinux += $(call ld-option,--orphan-handling=warn)
 
 ifeq ($(CONFIG_PPC64),y)
 ifeq ($(call cc-option-yn,-mcmodel=medium),y)
index e69155f0db364bb7a138f88b3d1a5ee240969e68..ace6b6579961f41007c83f6e0ce7d432295973c5 100644 (file)
@@ -91,7 +91,7 @@ SECTIONS
                ALIGN_FUNCTION();
 #endif
                /* careful! __ftr_alt_* sections need to be close to .text */
-               *(.text .fixup __ftr_alt_* .ref.text)
+               *(.text.hot .text .text.fixup .text.unlikely .fixup __ftr_alt_* .ref.text);
                SCHED_TEXT
                CPUIDLE_TEXT
                LOCK_TEXT
@@ -258,7 +258,9 @@ SECTIONS
        .data : AT(ADDR(.data) - LOAD_OFFSET) {
                DATA_DATA
                *(.sdata)
+               *(.sdata2)
                *(.got.plt) *(.got)
+               *(.plt)
        }
 #else
        .data : AT(ADDR(.data) - LOAD_OFFSET) {
@@ -321,6 +323,16 @@ SECTIONS
        _end = . ;
        PROVIDE32 (end = .);
 
-       /* Sections to be discarded. */
+       STABS_DEBUG
+
+       DWARF_DEBUG
+
        DISCARDS
+       /DISCARD/ : {
+               *(*.EMB.apuinfo)
+               *(.glink .iplt .plt .rela* .comment)
+               *(.gnu.version*)
+               *(.gnu.attributes)
+               *(.eh_frame)
+       }
 }
index 314a0b9219c64704151ad50680bd89d133f1af57..9862afb3ae05994aaefb660e63fb3eb0f5bd07fe 100644 (file)
 #define SBSS(sbss_align)                                               \
        . = ALIGN(sbss_align);                                          \
        .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) {                         \
+               *(.dynsbss)                                             \
                *(.sbss)                                                \
                *(.scommon)                                             \
        }
                .debug_str      0 : { *(.debug_str) }                   \
                .debug_loc      0 : { *(.debug_loc) }                   \
                .debug_macinfo  0 : { *(.debug_macinfo) }               \
+               .debug_pubtypes 0 : { *(.debug_pubtypes) }              \
+               /* DWARF 3 */                                           \
+               .debug_ranges   0 : { *(.debug_ranges) }                \
                /* SGI/MIPS DWARF 2 extensions */                       \
                .debug_weaknames 0 : { *(.debug_weaknames) }            \
                .debug_funcnames 0 : { *(.debug_funcnames) }            \
                .debug_typenames 0 : { *(.debug_typenames) }            \
                .debug_varnames  0 : { *(.debug_varnames) }             \
+               /* GNU DWARF 2 extensions */                            \
+               .debug_gnu_pubnames 0 : { *(.debug_gnu_pubnames) }      \
+               .debug_gnu_pubtypes 0 : { *(.debug_gnu_pubtypes) }      \
+               /* DWARF 4 */                                           \
+               .debug_types    0 : { *(.debug_types) }                 \
+               /* DWARF 5 */                                           \
+               .debug_macro    0 : { *(.debug_macro) }                 \
+               .debug_addr     0 : { *(.debug_addr) }
 
                /* Stabs debugging sections.  */
 #define STABS_DEBUG                                                    \