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Masahiro Yamada 04b8cb0945 kbuild: avoid unneeded kallsyms step 3
Since commit 951bcae6c5 ("kallsyms: Avoid weak references for kallsyms
symbols"), the kallsyms step 3 always occurs.

You can compare the build logs.

[Before 951bcae6c5]

  $ 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

[After 951bcae6c5]

  $ git checkout 951bcae6c5
  $ 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.

Since 951bcae6c5, 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>
2024-05-29 16:40:03 +09:00
arch 16 hotfixes, 11 of which are cc:stable. 2024-05-25 15:10:33 -07:00
block block-6.10-20240523 2024-05-23 13:44:47 -07:00
certs kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
crypto This push fixes a bug in the new ecc P521 code as well as a buggy 2024-05-20 08:47:54 -07:00
Documentation 16 hotfixes, 11 of which are cc:stable. 2024-05-25 15:10:33 -07:00
drivers ipmi: Mostly updates for deprecated interfaces 2024-05-25 14:32:29 -07:00
fs four smb client fixes, including two important netfs integration fixes 2024-05-25 22:33:10 -07:00
include mm: percpu: Include smp.h in alloc_tag.h 2024-05-26 14:40:39 -07:00
init Driver core changes for 6.10-rc1 2024-05-22 12:13:40 -07:00
io_uring io_uring-6.10-20240523 2024-05-23 13:41:49 -07:00
ipc Mainly singleton patches, documented in their respective changelogs. 2024-05-19 14:02:03 -07:00
kernel Misc fixes: 2024-05-25 14:48:40 -07:00
lib 16 hotfixes, 11 of which are cc:stable. 2024-05-25 15:10:33 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 16 hotfixes, 11 of which are cc:stable. 2024-05-25 15:10:33 -07:00
net NFS client updates for Linux 6.10 2024-05-23 13:51:09 -07:00
rust LoongArch changes for v6.10 2024-05-22 09:43:07 -07:00
samples tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
scripts kbuild: avoid unneeded kallsyms step 3 2024-05-29 16:40:03 +09:00
security hardening fixes for v6.10-rc1 2024-05-24 08:33:44 -07:00
sound sound fixes for 6.10-rc1 2024-05-24 08:48:51 -07:00
tools Revert a patch causing a regression as described in the cset: 2024-05-26 09:54:26 -07:00
usr kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
virt The usual shower of singleton fixes and minor series all over MM, 2024-05-19 09:21:03 -07:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig
.editorconfig Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: create a list of all built DTB files 2024-02-19 18:20:39 +09:00
.mailmap mailmap: update email address for Satya Priya 2024-05-24 11:55:05 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS MAINTAINERS: Drop Gustavo Pimentel as PCI DWC Maintainer 2024-03-27 13:41:02 -05:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS RTC for 6.10 2024-05-25 13:33:53 -07:00
Makefile Linux 6.10-rc1 2024-05-26 15:20:12 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.