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Nathan Chancellor 7f115ff4fc s390/boot: workaround current 'llvm-objdump -t -j ...' behavior
When building with OBJDUMP=llvm-objdump, there are a series of warnings
from the section comparisons that arch/s390/boot/Makefile performs
between vmlinux and arch/s390/boot/vmlinux:

  llvm-objdump: warning: section '.boot.preserved.data' mentioned in a -j/--section option, but not found in any input file
  llvm-objdump: warning: section '.boot.data' mentioned in a -j/--section option, but not found in any input file
  llvm-objdump: warning: section '.boot.preserved.data' mentioned in a -j/--section option, but not found in any input file
  llvm-objdump: warning: section '.boot.data' mentioned in a -j/--section option, but not found in any input file

The warning is a little misleading, as these sections do exist in the
input files. It is really pointing out that llvm-objdump does not match
GNU objdump's behavior of respecting '-j' / '--section' in combination
with '-t' / '--syms':

  $ s390x-linux-gnu-objdump -t -j .boot.data vmlinux.full

  vmlinux.full:     file format elf64-s390

  SYMBOL TABLE:
  0000000001951000 l     O .boot.data     0000000000003000 sclp_info_sccb
  00000000019550e0 l     O .boot.data     0000000000000001 sclp_info_sccb_valid
  00000000019550e2 g     O .boot.data     0000000000001000 early_command_line
  ...

  $ llvm-objdump -t -j .boot.data vmlinux.full

  vmlinux.full:   file format elf64-s390

  SYMBOL TABLE:
  0000000000100040 l     O .text  0000000000000010 dw_psw
  0000000000000000 l    df *ABS*  0000000000000000 main.c
  00000000001001b0 l     F .text  00000000000000c6 trace_event_raw_event_initcall_level
  0000000000100280 l     F .text  0000000000000100 perf_trace_initcall_level
  ...

It may be possible to change llvm-objdump's behavior to match GNU
objdump's behavior but the difficulty of that task has not yet been
explored. The combination of '$(OBJDUMP) -t -j' is not common in the
kernel tree on a whole, so workaround this tool difference by grepping
for the sections in the full symbol table output in a similar manner to
the sed invocation. This results in no visible change for GNU objdump
users while fixing the warnings for OBJDUMP=llvm-objdump, further
enabling use of LLVM=1 for ARCH=s390 with versions of LLVM that have
support for s390 in ld.lld and llvm-objcopy.

Reported-by: Heiko Carstens <hca@linux.ibm.com>
Closes: https://lore.kernel.org/20240219113248.16287-C-hca@linux.ibm.com/
Link: https://github.com/ClangBuiltLinux/linux/issues/859
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20240220-s390-work-around-llvm-objdump-t-j-v1-1-47bb0366a831@kernel.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-02-22 16:06:56 +01:00
arch s390/boot: workaround current 'llvm-objdump -t -j ...' behavior 2024-02-22 16:06:56 +01:00
block block: Fix where bio IO priority gets set 2024-02-01 11:00:06 -07:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto crypto: scomp - fix req->dst buffer overflow 2023-12-29 11:25:56 +08:00
Documentation USB driver fixes for 6.8-rc3 2024-02-04 06:52:29 +00:00
drivers s390/pci: introduce lock to synchronize state of zpci_dev's 2024-02-20 14:37:32 +01:00
fs Miscellaneous bug fixes and cleanups in ext4's multi-block allocator 2024-02-04 07:33:01 +00:00
include Compiler Attributes: Add __uninitialized macro 2024-02-09 13:58:16 +01:00
init Kconfig: Disable -Wstringop-overflow for GCC globally 2024-02-01 14:57:17 -08:00
io_uring io_uring/net: fix sr->len for IORING_OP_RECV with MSG_WAITALL and buffers 2024-02-01 06:42:36 -07:00
ipc shm: Slim down dependencies 2023-12-20 19:26:31 -05:00
kernel Tracing and eventfs fixes for v6.8: 2024-02-02 15:32:58 -08:00
lib s390/raid6: convert to use standard fpu_*() inline assemblies 2024-02-16 14:30:17 +01:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 22 hotfixes. 11 are cc:stable and the remainder address post-6.7 issues 2024-01-29 17:12:16 -08:00
net Including fixes from netfilter. 2024-02-01 12:39:54 -08:00
rust Rust changes for v6.8 2024-01-11 13:05:41 -08:00
samples samples/cgroup: add .gitignore file for generated samples 2024-01-24 11:52:40 -08:00
scripts Kbuild fixes for v6.8 2024-02-01 11:57:42 -08:00
security lsm/stable-6.8 PR 20240131 2024-02-01 10:00:28 -08:00
sound ASoC: Fixes for v6.8 2024-02-01 19:40:42 +01:00
tools KVM: s390: selftests: memop: add a simple AR test 2024-02-22 16:06:56 +01:00
usr Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
virt Generic: 2024-01-17 13:03:37 -08:00
.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 get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.mailmap Char/Misc and other Driver changes for 6.8-rc1 2024-01-17 16:47:17 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS MAINTAINERS: supplement of zswap maintainers update 2024-01-25 23:52:21 -08:00
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 MAINTAINERS update to point people to the new tree for i2c host driver 2024-02-04 06:47:45 +00:00
Makefile Linux 6.8-rc3 2024-02-04 12:20:36 +00:00
README

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 Restructured Text 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.