Commit Graph

4 Commits

Author SHA1 Message Date
Arnd Bergmann 6e8d96909a asm-generic: partially revert "Unify uapi bitsperlong.h for arm64, riscv and loongarch"
Unifying the asm-generic headers across 32-bit and 64-bit architectures
based on the compiler provided macros was a good idea and appears to work
with all user space, but it caused a regression when building old kernels
on systems that have the new headers installed in /usr/include, as this
combination trips an inconsistency in the kernel's own tools/include
headers that are a mix of userspace and kernel-internal headers.

This affects kernel builds on arm64, riscv64 and loongarch64 systems that
might end up using the "#define __BITS_PER_LONG 32" default from the old
tools headers. Backporting the commit into stable kernels would address
this, but it would still break building kernels without that backport,
and waste time for developers trying to understand the problem.

arm64 build machines are rather common, and on riscv64 this can also
happen in practice, but loongarch64 is probably new enough to not
be used much for building old kernels, so only revert the bits
for arm64 and riscv.

Link: https://lore.kernel.org/all/20230731160402.GB1823389@dev-arch.thelio-3990X/
Reported-by: Nathan Chancellor <nathan@kernel.org>
Fixes: 8386f58f8d ("asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch")
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-08-17 14:51:20 +02:00
Tiezhu Yang 8386f58f8d asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch
Now we specify the minimal version of GCC as 5.1 and Clang/LLVM as 11.0.0
in Documentation/process/changes.rst, __CHAR_BIT__ and __SIZEOF_LONG__ are
usable, it is probably fine to unify the definition of __BITS_PER_LONG as
(__CHAR_BIT__ * __SIZEOF_LONG__) in asm-generic uapi bitsperlong.h.

In order to keep safe and avoid regression, only unify uapi bitsperlong.h
for some archs such as arm64, riscv and loongarch which are using newer
toolchains that have the definitions of __CHAR_BIT__ and __SIZEOF_LONG__.

Suggested-by: Xi Ruoyao <xry111@xry111.site>
Link: https://lore.kernel.org/all/d3e255e4746de44c9903c4433616d44ffcf18d1b.camel@xry111.site/
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/linux-arch/a3a4f48a-07d4-4ed9-bc53-5d383428bdd2@app.fastmail.com/
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-06-22 17:04:36 +02:00
Thomas Gleixner caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00
Aurelien Jarno d0df00e30e
tools uapi: fix RISC-V 64-bit support
The BPF library is not built on 64-bit RISC-V, as the BPF feature is
not detected. Looking more in details, feature/test-bpf.c fails to build
with the following error:

| In file included from /tmp/linux-4.19.12/tools/include/uapi/asm/bitsperlong.h:17,
|                  from /tmp/linux-4.19.12/tools/include/uapi/asm-generic/unistd.h:2,
|                  from /usr/include/riscv64-linux-gnu/asm/unistd.h:1,
|                  from test-bpf.c:2:
| /tmp/linux-4.19.12/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h
|  #error Inconsistent word size. Check asm/bitsperlong.h
|   ^~~~~

The UAPI from the tools directory is missing RISC-V support, therefore
bitsperlong.h from asm-generic is used, defaulting to 32 bits.

Fix that by adding tools/arch/riscv/include/uapi/asm/bitsperlong.h as
a copy of arch/riscv/include/uapi/asm/bitsperlong.h and by updating
tools/include/uapi/asm/bitsperlong.h.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-01-07 07:59:28 -08:00