[ Upstream commit
adfae8a5d833fa2b46577a8081f350e408851f5b ]
I encountered this bug when using /proc/kcore to examine the kernel. Plus a
coworker inquired about debugging tools. We computed pa but did
not use it during the maximum physical address bits test. Instead we used
the identity mapped virtual address which will always fail this test.
I believe the defect came in here:
[bpicco@zareason linus.git]$ git describe --contains
bb4e6e85daa52
v3.18-rc1~87^2~4
.
Signed-off-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
if ((long)addr < 0L) {
unsigned long pa = __pa(addr);
- if ((addr >> max_phys_bits) != 0UL)
+ if ((pa >> max_phys_bits) != 0UL)
return false;
return pfn_valid(pa >> PAGE_SHIFT);