From 24e45bbe695719dca8c20e03d386eb6ea86526b5 Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Tue, 3 Jun 2008 23:36:11 -0300 Subject: [PATCH] thinkpad-acpi: fix LED handling on older ThinkPads The less tested codepaths for LED handling, used on ThinkPads 570, 600e/x, 770e, 770x, A21e, A2xm/p, T20-22, X20 and maybe a few others, would write data to kernel memory it had no business touching, for leds number 3 and above. If one is lucky, that illegal write would cause an OOPS, but chances are it would silently corrupt a byte. The problem was introduced in commit af116101, "ACPI: thinkpad-acpi: add sysfs led class support to thinkpad leds (v3.2)". Fix the bug by refactoring the entire code to be far more obvious on what it wants to do. Also do some defensive "constification". Issue reported by Karol Lewandowski (he's an lucky guy and got an OOPS instead of silent corruption :-) ). Root cause of the OOPS identified by Adrian Bunk . Thanks, Adrian! Signed-off-by: Henrique de Moraes Holschuh Tested-by: Karol Lewandowski Signed-off-by: Len Brown --- Reading git-format-patch failed