linux-yocto/scripts/mksysmap
Arnd Bergmann fa3866b67d kallsyms: ignore ARMv4 thunks along with others
[ Upstream commit a951884d82 ]

lld is now able to build ARMv4 and ARMv4T kernels, which means it can
generate thunks for those (__ARMv4PILongThunk_*, __ARMv4PILongBXThunk_*)
that can interfere with kallsyms table generation since they do not get
ignore like the corresponding ARMv5+ ones are:

Inconsistent kallsyms data
Try "make KALLSYMS_EXTRA_PASS=1" as a workaround

Replace the hardcoded list of thunk symbols with a more general regex that
covers this one along with future symbols that follow the same pattern.

Fixes: 5eb6e28043 ("ARM: 9289/1: Allow pre-ARMv5 builds with ld.lld 16.0.0 and newer")
Fixes: efe6e30680 ("kallsyms: fix nonconverging kallsyms table with lld")
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-23 09:24:59 +01:00

2.6 KiB
Executable File

#!/bin/sh -x

Based on the vmlinux file create the System.map file

System.map is used by module-init tools and some debugging

tools to retrieve the actual addresses of symbols in the kernel.

Usage

mksysmap vmlinux System.map [exclude]

Generate System.map (actual filename passed as second argument)

The following refers to the symbol type as per nm(1).

readprofile starts reading symbols when _stext is found, and

continue until it finds a symbol which is not either of 'T', 't',

'W' or 'w'.

${NM} -n ${1} | sed >${2} -e "

---------------------------------------------------------------------------

Ignored symbol types

a: local absolute symbols

N: debugging symbols

U: undefined global symbols

w: local weak symbols

/ [aNUw] /d

---------------------------------------------------------------------------

Ignored prefixes

(do not forget a space before each pattern)

local symbols for ARM, MIPS, etc.

/ \$/d

local labels, .LBB, .Ltmpxxx, .L__unnamed_xx, .LASANPC, etc.

/ .L/d

arm64 EFI stub namespace

/ _efistub/d

arm64 local symbols in PIE namespace

/ _pi\$/d / _pi.L/d

arm64 local symbols in non-VHE KVM namespace

/ _kvm_nvhe\$/d / _kvm_nvhe.L/d

lld arm/aarch64/mips thunks

/ _:alnum:*Thunk/d

CFI type identifiers

/ _kcfi_typeid/d / _kvm_nvhe___kcfi_typeid/d / _pi___kcfi_typeid/d

CRC from modversions

/ _crc/d

EXPORT_SYMBOL (symbol name)

/ _kstrtab/d

EXPORT_SYMBOL (namespace)

/ _kstrtabns/d

---------------------------------------------------------------------------

Ignored suffixes

(do not forget '$' after each pattern)

arm

/_from_arm$/d /_from_thumb$/d /_veneer$/d

---------------------------------------------------------------------------

Ignored symbols (exact match)

(do not forget a space before and '$' after each pattern)

for LoongArch?

/ L0$/d

ppc

/ SDA_BASE$/d / SDA2_BASE$/d

---------------------------------------------------------------------------

Ignored patterns

(symbols that contain the pattern are ignored)

ppc stub

/.long_branch./d /.plt_branch./d

---------------------------------------------------------------------------

Ignored kallsyms symbols

If the 3rd parameter exists, symbols from it will be omitted from the output.

This makes kallsyms have the identical symbol lists in the step 1 and 2.

Without this, the step2 would get new symbols generated by scripts/kallsyms.c

when CONFIG_KALLSYMS_ALL is enabled. That might require one more pass.

$(if [ $# -ge 3 ]; then ${NM} {3} | sed -n '/ U /!s:.* \([^ ]*\):/ \1$/d:p'; fi) "