• Olof Johansson's avatar
    [PATCH] Fix PCI BAR size interpretation on 64-bit arches · f797f9cc
    Olof Johansson authored
    On 64-bit machines, PCI_BASE_ADDRESS_MEM_MASK and other mask constants
    passed to pci_size() are 64-bit (for example ~0x0fUL).  However, pci_size
    does comparisons between the u32 arguments and the mask, which will fail
    even though any result from pci_size is still just 32-bit.
    
    Changing the mask argument to u32 seems the obvious thing to do, since all
    arithmetic in the function is 32-bit and having a larger mask makes no
    sense.
    
    This triggered on a PPC64 system here where an adapter (VGA, as it
    happened) had a memory region base of 0xfe000000 and a sz of the same,
    matching the if (max == maxbase ...) test at the bottom of pci_size but
    failing the mask comparison.  Quite a corner case which I guess explains
    why we haven't seen it until now.
    Signed-off-by: default avatarOlof Johansson <olof@lixom.net>
    Acked-by: default avatarGreg KH <greg@kroah.com>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    f797f9cc
probe.c 25.1 KB