Paul Walmsley
53a7d908b4
modpost: skip ELF local symbols during section mismatch check ...
[ Upstream commit a4d26f1a0958bb1c2b60c6f1e67c6f5d43e2647b ]
During development of a serial console driver with a gcc 8.2.0
toolchain for RISC-V, the following modpost warning appeared:
----
WARNING: vmlinux.o(.data+0x19b10): Section mismatch in reference from the variable .LANCHOR1 to the function .init.text:sifive_serial_console_setup()
The variable .LANCHOR1 references
the function __init sifive_serial_console_setup()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console
----
".LANCHOR1" is an ELF local symbol, automatically created by gcc's section
anchor generation code:
https://gcc.gnu.org/onlinedocs/gccint/Anchored-Addresses.html
https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/varasm.c;h=cd9591a45617464946dcf9a126dde277d9de9804;hb=9fb89fa845c1b2e0a18d85ada0b077c84508ab78#l7473
This was verified by compiling the kernel with -fno-section-anchors
and observing that the ".LANCHOR1" ELF local symbol disappeared, and
modpost no longer warned about the section mismatch. The serial
driver code idiom triggering the warning is standard Linux serial
driver practice that has a specific whitelist inclusion in modpost.c.
I'm neither a modpost nor an ELF expert, but naively, it doesn't seem
useful for modpost to report section mismatch warnings caused by ELF
local symbols by default. Local symbols have compiler-generated
names, and thus bypass modpost's whitelisting algorithm, which relies
on the presence of a non-autogenerated symbol name. This increases
the likelihood that false positive warnings will be generated (as in
the above case).
Thus, disable section mismatch reporting on ELF local symbols. The
rationale here is similar to that of commit 2e3a10a155https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/mod/modpost.c?h=v4.19-rc4&id=7876320f88802b22d4e2daf7eb027dd14175a0f8#n1256
This third version of the patch implements a suggestion from Masahiro
Yamada <yamada.masahiro@socionext.com> to restructure the code as an
additional pattern matching step inside secref_whitelist(), and
further improves the patch description.
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-21 10:41:17 +01:00
fixdep: faster CONFIG_ search
2016-08-24 22:34:19 +02:00
fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock
2019-06-11 12:22:49 +02:00
scripts/dtc: dt_to_config - kernel config options for a devicetree
2016-07-22 14:48:16 -05:00
gcc-plugins: Fix build failures under Darwin host
2019-06-11 12:22:43 +02:00
scripts/gdb: fix debugging modules compiled with hot/cold partitioning
2019-12-05 15:34:10 +01:00
kbuild: Regenerate genksyms lexer
2016-08-25 20:03:51 +02:00
kconfig/[mn]conf: handle backspace (^H) key
2019-05-04 08:49:10 +02:00
modpost: skip ELF local symbols during section mismatch check
2019-12-21 10:41:17 +01:00
builddeb: Fix header package regarding dtc source links
2018-05-30 07:50:39 +02:00
selinux: explicitly declare the role "base_r"
2015-07-13 13:32:00 -04:00
ftrace/scripts: Add helper script to bisect function tracing problem functions
2016-09-21 13:56:55 -04:00
KEYS: Reserve an extra certificate symbol for inserting without recompiling
2016-02-26 15:30:20 +00:00
kbuild: make scripts/adjust_autoksyms.sh robust against timestamp races
2018-05-30 07:50:37 +02:00
PM / tools: scripts: AnalyzeSuspend v4.2
2016-07-15 23:34:14 +02:00
ASN.1: fix open failure check on headername
2016-04-06 14:06:48 +01:00
scripts/bloat-o-meter: fix SIGPIPE
2016-11-11 08:12:37 -08:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
DocBook: Use a fixed encoding for output
2015-09-28 01:31:48 -06:00
scripts: add check_extable.sh script.
2015-04-13 21:03:02 +09:30
checkkconfigsymbols: use arglist instead of cmd string
2016-08-28 11:08:34 +02:00
checkpatch: silence perl 5.26.0 unescaped left brace warnings
2017-07-21 07:42:21 +02:00
scripts/checkstack.pl: Fix arm64 wrong or unknown architecture
2019-07-10 09:55:31 +02:00
x86/asm/entry: Move the arch/x86/syscalls/ definitions to arch/x86/entry/syscalls/
2015-06-04 07:37:37 +02:00
coccinelle: fix parallel build with CHECK=scripts/coccicheck
2017-12-14 09:28:22 +01:00
kbuild: trivial - remove trailing empty lines
2014-06-10 00:04:06 +02:00
kbuild: trivial - remove trailing spaces
2014-04-30 17:34:32 +02:00
const_structs.checkpatch: add frequently used from Julia Lawall's list
2016-10-11 15:06:30 -07:00
scripts/decode_stacktrace: match basepath using shell prefix operator, not regex
2019-09-16 08:19:33 +02:00
kbuild: make missing $DEPMOD a Warning instead of an Error
2018-09-15 09:43:01 +02:00
vfs,ext2: remove CONFIG_EXT2_FS_XIP and rename CONFIG_FS_XIP to CONFIG_FS_DAX
2015-02-16 17:56:04 -08:00
docproc: print a comment about autogeneration for rst output
2016-05-14 09:56:56 -06:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
KEYS: Remove unnecessary header #inclusions from extract-cert.c
2015-09-25 16:31:45 +01:00
scripts/extract-ikconfig: Support LZ4-compressed images.
2015-04-15 14:01:12 +02:00
KEYS: Provide a script to extract a module signature
2015-10-21 15:18:36 +01:00
KEYS: Use the symbol value for list size, updated by scripts/insert-sys-cert
2016-02-26 15:32:05 +00:00
[media] extract_xc3028.pl: move it to scripts/dir
2016-07-17 14:08:12 -03:00
scripts/faddr2line: improve on base path filtering a bit
2016-09-19 14:49:08 -07:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
gcc-plugins: abort builds cleanly when not supported
2016-08-08 17:49:05 -07:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
scripts/has-stack-protector: add -fno-PIE
2016-11-09 22:28:05 +01:00
initramfs: Escape colons in depfile
2016-09-23 10:35:32 +02:00
[media] doc-rst: move DVB avulse docs to Documentation/media
2016-07-17 14:02:45 -03:00
get_maintainer: quiet noisy implicit -f vcs_file_exists checking
2016-08-26 17:39:34 -07:00
CRIS: Fix headers_install
2014-12-20 00:01:12 +01:00
headers_check: don't warn about c++ guards
2016-05-24 14:12:48 +10:00
Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
2014-10-14 09:22:26 +02:00
KEYS: Reserve an extra certificate symbol for inserting without recompiling
2016-02-26 15:30:20 +00:00
kallsyms: exclude kasan local symbols on s390
2019-08-04 09:33:40 +02:00
kbuild: simplify ld-option implementation
2019-05-02 09:31:59 +02:00
scripts/kernel-doc: Don't fail with status != 0 if error encountered with -none
2018-02-25 11:05:47 +01:00
scripts/kernel-doc: Adding cross-reference links to html documentation.
2015-08-16 22:11:16 -06:00
ld-version: Drop the 4th and 5th version components
2016-05-13 14:02:05 +02:00
scripts/Lindent: handle missing indent gracefully
2015-09-04 16:54:41 -07:00
kbuild: allow architectures to use thin archives instead of ld -r
2016-09-09 10:31:19 +02:00
GCC plugin infrastructure
2016-06-07 22:57:10 +02:00
kbuild: Remove stale asm-generic wrappers
2016-07-07 15:58:45 +02:00
kbuild: Add support to generate LLVM assembly files
2018-11-23 08:20:35 +01:00
Shared library support
2016-06-07 22:57:10 +02:00
dtbsinstall: don't move target directory out of the way
2016-01-28 11:40:32 +01:00
Kbuild: suppress packed-not-aligned warning for default setting only
2018-12-08 13:05:04 +01:00
kbuild: include $(src)/Makefile rather than $(obj)/Makefile
2015-04-02 16:42:08 +02:00
gcc-plugins: Add latent_entropy plugin
2016-10-10 14:51:44 -07:00
kbuild: collect shorthands into scripts/Kbuild.include
2014-11-26 14:36:52 +01:00
kbuild: Add __cc-option macro
2018-11-23 08:20:35 +01:00
kasan: don't emit builtin calls when sanitization is off
2018-08-17 20:59:29 +02:00
kbuild: fix asm-offset generation to work with clang
2018-11-23 08:20:35 +01:00
modsign: Abort modules_install when signing fails
2015-08-07 16:26:13 +01:00
kbuild: modpost: handle KBUILD_EXTRA_SYMBOLS only for external modules
2019-08-25 10:51:47 +02:00
modsign: lookup lines ending in .ko in .mod files
2014-08-27 21:54:11 +09:30
Kbuild: enable -Wmaybe-uninitialized warning for "make W=1"
2016-11-11 08:45:08 -08:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
kbuild: trivial - remove trailing spaces
2014-04-30 17:34:32 +02:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
mksysmap: Add h8300 local symbol pattern
2015-06-23 13:35:47 +09:00
objtool, modules: Discard objtool annotation sections for modules
2018-01-17 09:38:58 +01:00
namespace: fix namespace.pl script to support relative paths
2019-10-29 09:15:06 +01:00
scripts: objdiff: support directories for the augument of record command
2014-06-10 14:59:33 +02:00
kbuild: trivial - remove trailing spaces
2014-04-30 17:34:32 +02:00
kbuild: trivial - remove trailing empty lines
2014-06-10 00:04:06 +02:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
scripts: add "prune-kernel" script to clean up old kernel images
2016-02-09 10:09:52 -08:00
nmi_backtrace: generate one-line reports for idle cpus
2016-10-07 18:46:30 -07:00
recordmcount: Fix spurious mcount entries on powerpc
2019-08-04 09:33:38 +02:00
nmi_backtrace: generate one-line reports for idle cpus
2016-10-07 18:46:30 -07:00
scripts/setlocalversion: Improve -dirty check with git-status --no-optional-locks
2019-11-06 12:18:03 +01:00
kbuild: trivial - remove trailing empty lines
2014-06-10 00:04:06 +02:00
modsign: Make sign-file determine the format of the X.509 cert
2016-06-14 13:18:33 +01:00
parisc: Use generic extable search and sort routines
2016-03-23 16:00:46 +01:00
scripts/sortextable: suppress warning: `relocs_size' may be used uninitialized
2014-10-14 02:18:23 +02:00
spelling.txt: "modeled" is spelt correctly
2016-10-07 18:46:30 -07:00
scripts: add stackdelta script
2015-08-28 17:04:40 +02:00
scripts: add stackusage script
2015-08-28 17:04:40 +02:00
tags: honor COMPILED_SOURCE with apart output directory
2018-04-13 19:48:21 +02:00
unifdef: use memcpy instead of strncpy
2018-12-08 13:05:05 +01:00
ver_linux: rename ver_linux.awk to ver_linux
2016-08-31 13:59:31 +02:00
xen: build infrastructure for generating hypercall depending symbols
2015-03-16 14:49:13 +00:00
kbuild: Make scripts executable
2014-08-20 16:03:45 +02:00
53a7d908b4