• Michael Holzheu's avatar
    kernel: Fix s390 absolute memory access for /dev/mem · 576ebd74
    Michael Holzheu authored
    On s390 the prefix page and absolute zero pages are not correctly
    returned when reading /dev/mem. The reason is that the s390 asm/io.h
    file includes the asm-generic/io.h file which then defines
    xlate_dev_mem_ptr() and therefore overwrites the s390 specific
    version that does the correct swap operation for prefix and absolute
    zero pages. The problem is a regression that was introduced with git
    commit cd248341 (s390/pci: base support).
    To fix the problem add "#ifndef xlate_dev_mem_ptr" in asm-generic/io.h
    and "#define xlate_dev_mem_ptr" in asm/io.h. This ensures that the
    s390 version is used. For completeness also add the "#ifndef"
    construct for xlate_dev_kmem_ptr().
    Signed-off-by: default avatarMichael Holzheu <holzheu@linux.vnet.ibm.com>
    Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
io.h 8.35 KB