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Since commit951bcae6c5
("kallsyms: Avoid weak references for kallsyms symbols"), the kallsyms step 3 always occurs. You can compare the build logs. [Before951bcae6c5
] $ git checkout 951bcae6c5a0^ $ make defconfig all [ snip ] LD .tmp_vmlinux.kallsyms1 NM .tmp_vmlinux.kallsyms1.syms KSYMS .tmp_vmlinux.kallsyms1.S AS .tmp_vmlinux.kallsyms1.S LD .tmp_vmlinux.kallsyms2 NM .tmp_vmlinux.kallsyms2.syms KSYMS .tmp_vmlinux.kallsyms2.S AS .tmp_vmlinux.kallsyms2.S LD vmlinux [After951bcae6c5
] $ git checkout951bcae6c5
$ make defconfig all [ snip ] LD .tmp_vmlinux.kallsyms1 NM .tmp_vmlinux.kallsyms1.syms KSYMS .tmp_vmlinux.kallsyms1.S AS .tmp_vmlinux.kallsyms1.S LD .tmp_vmlinux.kallsyms2 NM .tmp_vmlinux.kallsyms2.syms KSYMS .tmp_vmlinux.kallsyms2.S AS .tmp_vmlinux.kallsyms2.S LD .tmp_vmlinux.kallsyms3 # should not happen NM .tmp_vmlinux.kallsyms3.syms # should not happen KSYMS .tmp_vmlinux.kallsyms3.S # should not happen AS .tmp_vmlinux.kallsyms3.S # should not happen LD vmlinux The resulting vmlinux is correct, but it always requires an additional linking step. The symbols produced by kallsyms are excluded from kallsyms itself because they were previously missing in step 1. With those symbols excluded, the symbol lists matched between step 1 and step 2, eliminating the need for step 3. Now, this has a negative effect. Since951bcae6c5
, the PROVIDE() directives provide the fallback definitions, which are not trimmed from the sysbol list in step 1 because ${kallsymso_prev} is empty at this point. In step 2, ${kallsymso_prev} is set, and the kallsyms_* symbols are trimmed from the symbol list. Due to the table size difference between step 1 and step 2 (the former is larger due to the presence of kallsyms_*), step 3 is triggered. Now that the kallsyms_* symbols are always linked, let's stop omitting them from kallsyms. This avoids unnecessary step 3. Fixes:951bcae6c5
("kallsyms: Avoid weak references for kallsyms symbols") Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2.1 KiB
Executable File
2.1 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
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 "