From dc810efb0ca5702c9d96782b99282d4b4383e877 Mon Sep 17 00:00:00 2001 From: Pawel Moll Date: Wed, 16 Feb 2011 18:54:01 +0100 Subject: [PATCH] ARM: 6740/1: Place correctly notes section in the linker script Commit 18991197b4b588255ccabf472ebc84db7b66a19c added --build-id linker option when toolchain supports it. ARM one does, but for some reason places the section at 0 when linker script doesn't mention it explicitly. The 1e621a8e3752367d4aae78a8ab00a18fb2793f34 worked around the problem removing this section from binary image with explicit objcopy options, but it still exists in vmlinux, confusing tools like debuggers and perf. This problem was discussed here: http://lists.infradead.org/pipermail/linux-arm-kernel/2010-May/015994.html http://lists.infradead.org/pipermail/linux-arm-kernel/2010-May/015994.html but the proposed changes to the linker script were substantial. This patch simply places NOTES (36 bytes long, at least when compiled with CodeSourcery toolchain) between data and bss, which seem to be the right place (and suggested by the sample linker script in include/asm-generic/vmlinux.lds.h). It is enough to place it correctly in vmlinux (so debuggers are happy): Section Headers: [11] .data PROGBITS c07ce000 7ce000 020fc0 00 WA 0 0 32 [12] .notes NOTE c07eefc0 7eefc0 000024 00 AX 0 0 4 [13] .bss NOBITS c07ef000 7eefe4 01e628 00 WA 0 0 32 Program Headers: LOAD 0x008000 0xc0008000 0xc0008000 0x7e6fe4 0x805628 RWE 0x8000 NOTE 0x7eefc0 0xc07eefc0 0xc07eefc0 0x00024 0x00024 R E 0x4 Section to Segment mapping: Segment Sections... 00 <...> .data .notes .bss 01 .notes and to get it exposed as /sys/kernel/notes used by perf tools. Signed-off-by: Pawel Moll Signed-off-by: Russell King --- arch/arm/Makefile | 2 +- arch/arm/kernel/vmlinux.lds.S | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm/Makefile b/arch/arm/Makefile index c22c1adfedd6..6f7b29294c80 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -15,7 +15,7 @@ ifeq ($(CONFIG_CPU_ENDIAN_BE8),y) LDFLAGS_vmlinux += --be8 endif -OBJCOPYFLAGS :=-O binary -R .note -R .note.gnu.build-id -R .comment -S +OBJCOPYFLAGS :=-O binary -R .comment -S GZFLAGS :=-9 #KBUILD_CFLAGS +=-pipe # Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb: diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index 86b66f3f2031..558bd81a4fce 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -247,6 +247,8 @@ SECTIONS } #endif + NOTES + BSS_SECTION(0, 0, 0) _end = .; -- GitLab