tree e1e8224f9e9fbe83d76dfdaf7eb77cca7ff8ca3b
parent 2ac13a8f46246a8a3773bfca0a003f0524cf7cf0
author David Jander <david@protonic.nl> 1377099442 +0200
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1378617000 -0700

regmap: rbtree: Fix overlapping rbnodes.

commit 4e67fb5f5e336250db944921e3c68057d6203034 upstream.

Avoid overlapping register regions by making the initial blklen of a new
node 1. If a register write occurs to a yet uncached register, that is
lower than but near an existing node's base_reg, a new node is created
and it's blklen is set to an arbitrary value (sizeof(*rbnode)). That may
cause this node to overlap with another node. Those nodes should be merged,
but this merge doesn't happen yet, so this patch at least makes the initial
blklen small enough to avoid hitting the wrong node, which may otherwise
lead to severe breakage.

Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Zhouping Liu <zliu@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>