From 870d6656126add8e383645732b03df2b7ccd4f94 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 25 Aug 2008 19:47:25 +0900 Subject: block: implement CONFIG_DEBUG_BLOCK_EXT_DEVT Extended devt introduces non-contiguos device numbers. This patch implements a debug option which forces most devt allocations to be from the extended area and spreads them out. This is enabled by default if DEBUG_KERNEL is set and achieves... 1. Detects code paths in kernel or userland which expect predetermined consecutive device numbers. 2. When something goes wrong, avoid corruption as adding to the minor of earlier partition won't lead to the wrong but valid device. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- lib/Kconfig.debug | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 0b504814e37..5a536f703a8 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -624,6 +624,22 @@ config BACKTRACE_SELF_TEST Say N if you are unsure. +config DEBUG_BLOCK_EXT_DEVT + bool "Force extended block device numbers and spread them" + depends on DEBUG_KERNEL + depends on BLOCK + default y + help + Conventionally, block device numbers are allocated from + predetermined contiguous area. However, extended block area + may introduce non-contiguous block device numbers. This + option forces most block device numbers to be allocated from + the extended space and spreads them to discover kernel or + userland code paths which assume predetermined contiguous + device number allocation. + + Say N if you are unsure. + config LKDTM tristate "Linux Kernel Dump Test Tool Module" depends on DEBUG_KERNEL -- cgit v1.2.3