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[PATCH] Fix PCI BAR size interpretation on 64-bit arches 

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: Olof Johansson <olof@lixom.net>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Olof Johansson 2005-06-13 15:52:27 -07:00 committed by Linus Torvalds
parent a3c77c67a4
commit f797f9cc54
1 changed files with 1 additions and 1 deletions
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2
drivers/pci/probe.c
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@ -125,7 +125,7 @@ static inline unsigned int pci_calc_resource_flags(unsigned int flags)
/*
* Find the extent of a PCI decode..
*/
static u32 pci_size(u32 base, u32 maxbase, unsigned long mask)
static u32 pci_size(u32 base, u32 maxbase, u32 mask)
{
u32 size = mask & maxbase; /* Find the significant bits */
if (!size)