4241cfc973
[ Upstream commit 79e8328e5acbe691bbde029a52c89d70dcbc22f3 ]
Compiling big-endian targets with Clang produces the diagnostic:
fs/namei.c:2173:13: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical]
} while (!(has_zero(a, &adata, &constants) | has_zero(b, &bdata, &constants)));
~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
||
fs/namei.c:2173:13: note: cast one or both operands to int to silence this warning
It appears that when has_zero was introduced, two definitions were
produced with different signatures (in particular different return
types).
Looking at the usage in hash_name() in fs/namei.c, I suspect that
has_zero() is meant to be invoked twice per while loop iteration; using
logical-or would not update `bdata` when `a` did not have zeros. So I
think it's preferred to always return an unsigned long rather than a
bool than update the while loop in hash_name() to use a logical-or
rather than bitwise-or.
[ Also changed powerpc version to do the same - Linus ]
Link: https://github.com/ClangBuiltLinux/linux/issues/1832
Link: https://lore.kernel.org/lkml/20230801-bitwise-v1-1-799bec468dc4@google.com/
Fixes: 36126f8f2ed8 ("word-at-a-time: make the interfaces truly generic")
Debugged-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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.