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Nathan Chancellor fd9d0ca2cc MIPS: Unconditionally specify '-EB' or '-EL'
This was all done to work around a GCC bug that has been fixed after
4.2. The kernel requires GCC 4.6 or newer so remove all of these hacks
and just use the traditional flags.

 $ mips64-linux-gcc --version | head -n1
 mips64-linux-gcc (GCC) 4.6.3

 $ mips64-linux-gcc -EB -dM -E -C -x c /dev/null | grep MIPSE
 #define MIPSEB 1
 #define __MIPSEB__ 1
 #define _MIPSEB 1
 #define __MIPSEB 1

 $ mips64-linux-gcc -EL -dM -E -C -x c /dev/null | grep MIPSE
 #define __MIPSEL__ 1
 #define MIPSEL 1
 #define _MIPSEL 1
 #define __MIPSEL 1

This is necessary when converting the MIPS VDSO to use $(LD) instead of
$(CC) to link because the OUTPUT_FORMAT is defaulted to little endian
and only flips to big endian when '-EB' is set on the command line.
There is no issue currently because the compiler explicitly passes
'-EB' or '-EL' to the linker regardless of whether or not it was
provided by the user. Passing '-v' to VDSO_LDFLAGS shows:

<gcc_prefix>/libexec/gcc/mips64-linux/9.3.0/collect2 ... -EB ...

even though '-EB' is nowhere to be found in KBUILD_CFLAGS. The VDSO
Makefile already supports getting '-EB' or '-EL' from KBUILD_CFLAGS
through a filter directive but '-EB' or '-EL' is not always present.

If we do not do this, we will see the following error when compiling
for big endian:

$ make -j$(nproc) ARCH=mips CROSS_COMPILE=mips64-linux- \
  64r2el_defconfig arch/mips/vdso/
...
mips64-linux-ld: arch/mips/vdso/elf.o: compiled for a big endian system
and target is little endian
mips64-linux-ld: arch/mips/vdso/elf.o: endianness incompatible with that
of the selected emulation
mips64-linux-ld: failed to merge target specific data of file
arch/mips/vdso/elf.o
...

Remove this legacy hack and just use '-EB' and '-EL' unconditionally.

Reported-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-05-12 10:01:53 +02:00
arch MIPS: Unconditionally specify '-EB' or '-EL' 2020-05-12 10:01:53 +02:00
block block-5.7-2020-04-10 2020-04-10 10:06:54 -07:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto x86: update AS_* macros to binutils >=2.23, supporting ADX and AVX2 2020-04-09 00:12:48 +09:00
Documentation dt-bindings: Document Loongson RS780E PCH ACPI Controller 2020-04-20 19:36:47 +02:00
drivers MIPS: Loongson64: Make RS780E ACPI as a platform driver 2020-04-20 19:36:40 +02:00
fs 10 smb fixes most RDMA (smbdirect) related, also add experimental support for swap over SMB3 mounts, and also adds fix which improves performance of signed connections 2020-04-12 09:41:01 -07:00
include Three small fixes/updates for the locking core code: 2020-04-12 09:47:10 -07:00
init kbuild: add CONFIG_LD_IS_LLD 2020-05-12 10:01:31 +02:00
ipc ipc/util.c: sysvipc_find_ipc() should increase position index 2020-04-10 15:36:22 -07:00
kernel Time(keeping) updates: 2020-04-12 10:13:14 -07:00
lib Kbuild updates for v5.7 (2nd) 2020-04-11 09:46:12 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Merge branch 'akpm' (patches from Andrew) 2020-04-10 17:57:48 -07:00
net Kbuild updates for v5.7 (2nd) 2020-04-11 09:46:12 -07:00
samples samples/hw_breakpoint: drop use of kallsyms_lookup_name() 2020-04-07 10:43:44 -07:00
scripts kbuild: add dummy toolchains to enable all cc-option etc. in Kconfig 2020-04-09 00:13:45 +09:00
security Keyrings fixes 2020-04-04 12:24:47 -07:00
sound ASoC: txx9: add back the hack for a too small resource_size_t 2020-04-21 20:01:50 +02:00
tools Kbuild updates for v5.7 (2nd) 2020-04-11 09:46:12 -07:00
usr kbuild: fix comment about missing include guard detection 2020-04-11 12:09:48 +09:00
virt KVM: Pass kvm_init()'s opaque param to additional arch funcs 2020-03-31 10:48:03 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2020-03-06 21:50:05 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
.mailmap mailmap: Add Sedat Dilek (replacement for expired email address) 2020-04-11 09:28:34 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Hand MIPS over to Thomas 2020-02-24 22:43:18 -08:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS MAINTAINERS: sort field names for all entries 2020-04-12 11:04:58 -07:00
Makefile Linux 5.7-rc1 2020-04-12 12:35:55 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -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 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.