tree a9b7bacbdf8e30b931c2ebd849104b04b157d48d
parent a92d3ff9e5dbd958d8008a3e7a573e988e370ca3
author Tejun Heo <tj@kernel.org> 1276854271 +0200
committer Tejun Heo <tj@kernel.org> 1276866443 +0200

percpu: fix first chunk match in per_cpu_ptr_to_phys()

per_cpu_ptr_to_phys() determines whether the passed in @addr belongs
to the first_chunk or not by just matching the address against the
address range of the base unit (unit0, used by cpu0).  When an adress
from another cpu was passed in, it will always determine that the
address doesn't belong to the first chunk even when it does.  This
makes the function return a bogus physical address which may lead to
crash.

This problem was discovered by Cliff Wickman while investigating a
crash during kdump on a SGI UV system.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Cliff Wickman <cpw@sgi.com>
Tested-by: Cliff Wickman <cpw@sgi.com>
Cc: stable@kernel.org