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Nathan Chancellor
6f4e626fb0
Clang warns several times in the scsi subsystem (trimmed for brevity):
drivers/scsi/hpsa.c:6209:7: warning: overflow converting case value to
switch condition type (2147762695 to 18446744071562347015) [-Wswitch]
case CCISS_GETBUSTYPES:
^
drivers/scsi/hpsa.c:6208:7: warning: overflow converting case value to
switch condition type (2147762694 to 18446744071562347014) [-Wswitch]
case CCISS_GETHEARTBEAT:
^
The root cause is that the _IOC macro can generate really large numbers,
which don't fit into type 'int', which is used for the cmd parameter in
the ioctls in scsi_host_template. My research into how GCC and Clang are
handling this at a low level didn't prove fruitful. However, looking at
the rest of the kernel tree, all ioctls use an 'unsigned int' for the
cmd parameter, which will fit all of the _IOC values in the scsi/ata
subsystems.
Make that change because none of the ioctls expect a negative value for
any command, it brings the ioctls inline with the reset of the kernel,
and it removes ambiguity, which is never good when dealing with compilers.
Link: https://github.com/ClangBuiltLinux/linux/issues/85
Link: https://github.com/ClangBuiltLinux/linux/issues/154
Link: https://github.com/ClangBuiltLinux/linux/issues/157
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Bradley Grove <bgrove@attotech.com>
Acked-by: Don Brace <don.brace@microsemi.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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.