Commit bbd4c45d authored by Dave Hansen's avatar Dave Hansen Committed by Linus Torvalds

[PATCH] make sure ioremap only tests valid addresses

When CONFIG_HIGHMEM=y, but ZONE_NORMAL isn't quite full, there is, of
course, no actual memory at *high_memory.  This isn't a problem with normal
virt<->phys translations because it's never dereferenced, but
CONFIG_NONLINEAR is a bit more finicky.  So, don't do virt_to_phys() to
non-existent addresses.
Signed-off-by: default avatarDave Hansen <haveblue@us.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 422e43d4
......@@ -135,7 +135,7 @@ void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned l
/*
* Don't allow anybody to remap normal RAM that we're using..
*/
if (phys_addr < virt_to_phys(high_memory)) {
if (phys_addr <= virt_to_phys(high_memory - 1)) {
char *t_addr, *t_end;
struct page *page;
......@@ -202,7 +202,7 @@ void __iomem *ioremap_nocache (unsigned long phys_addr, unsigned long size)
/* Guaranteed to be > phys_addr, as per __ioremap() */
last_addr = phys_addr + size - 1;
if (last_addr < virt_to_phys(high_memory)) {
if (last_addr < virt_to_phys(high_memory) - 1) {
struct page *ppage = virt_to_page(__va(phys_addr));
unsigned long npages;
......@@ -237,7 +237,7 @@ void iounmap(volatile void __iomem *addr)
return;
}
if (p->flags && p->phys_addr < virt_to_phys(high_memory)) {
if (p->flags && p->phys_addr < virt_to_phys(high_memory) - 1) {
change_page_attr(virt_to_page(__va(p->phys_addr)),
p->size >> PAGE_SHIFT,
PAGE_KERNEL);
......
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