From a3453d923ece6760689894bad5b6d5e00c0ffe2d Mon Sep 17 00:00:00 2001 From: Vasily Gorbik Date: Thu, 15 Oct 2020 10:01:42 +0200 Subject: s390/kasan: remove 3-level paging support Compiling the kernel with Kasan disables automatic 3-level vs 4-level kernel space paging selection, because the shadow memory offset has to be known at compile time and there is no such offset which would be acceptable for both 3 and 4-level paging. Instead S390_4_LEVEL_PAGING option was introduced which allowed to pick how many paging levels to use under Kasan. With the introduction of protected virtualization, kernel memory layout may be affected due to ultravisor secure storage limit. This adds additional complexity into how memory layout would look like in combination with Kasan predefined shadow memory offsets. To simplify this make Kasan 4-level paging default and remove Kasan 3-level paging support. Suggested-by: Heiko Carstens Reviewed-by: Alexander Gordeev Signed-off-by: Vasily Gorbik Signed-off-by: Heiko Carstens --- lib/Kconfig.kasan | 9 --------- 1 file changed, 9 deletions(-) (limited to 'lib') diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan index 542a9c18398e..8fb097057fec 100644 --- a/lib/Kconfig.kasan +++ b/lib/Kconfig.kasan @@ -136,15 +136,6 @@ config KASAN_STACK default 1 if KASAN_STACK_ENABLE || CC_IS_GCC default 0 -config KASAN_S390_4_LEVEL_PAGING - bool "KASan: use 4-level paging" - depends on S390 - help - Compiling the kernel with KASan disables automatic 3-level vs - 4-level paging selection. 3-level paging is used by default (up - to 3TB of RAM with KASan enabled). This options allows to force - 4-level paging instead. - config KASAN_SW_TAGS_IDENTIFY bool "Enable memory corruption identification" depends on KASAN_SW_TAGS -- cgit 1.4.1