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Linus Torvalds
498e47cd1d
Commit576882ef5e("uio: introduce UIO_MEM_DMA_COHERENT type") introduced a new use-case for 'struct uio_mem' where the 'mem' field now contains a kernel virtual address when 'memtype' is set to UIO_MEM_DMA_COHERENT. That in turn causes build errors, because 'mem' is of type 'phys_addr_t', and a virtual address is a pointer type. When the code just blindly uses cast to mix the two, it caused problems when phys_addr_t isn't the same size as a pointer - notably on 32-bit architectures with PHYS_ADDR_T_64BIT. The proper thing to do would probably be to use a union member, and not have any casts, and make the 'mem' member be a union of 'mem.physaddr' and 'mem.vaddr', based on 'memtype'. This is not that proper thing. This is just fixing the ugly casts to be even uglier, but at least not cause build errors on 32-bit platforms with 64-bit physical addresses. Reported-by: Guenter Roeck <linux@roeck-us.net> Fixes:576882ef5e("uio: introduce UIO_MEM_DMA_COHERENT type") Fixes:7722151e46("uio_pruss: UIO_MEM_DMA_COHERENT conversion") Fixes:019947805a("uio_dmem_genirq: UIO_MEM_DMA_COHERENT conversion") Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Chris Leech <cleech@redhat.com> Cc: Nilesh Javali <njavali@marvell.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linuxfoundation.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 reStructuredText 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.