From: Gerald Schaefer Date: Fri, 24 Feb 2012 17:01:29 +0000 (+0100) Subject: [S390] memory hotplug: prevent memory zone interleave X-Git-Tag: v3.3-rc6~20^2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=892365ab4d29ed861709ee8611b53587ca2bb75f;p=pandora-kernel.git [S390] memory hotplug: prevent memory zone interleave This fixes a kernel oops with CONFIG_DEBUG_VM triggered by a VM_BUG_ON(bad_range()): kernel BUG at mm/page_alloc.c:748. With memory hotplug on System z, it is possible that the memory online/offline state is preserved over a system restart, e.g. there may be offline memory blocks in ZONE_DMA or ZONE_NORMAL. So far, the offline memory range has always been added to ZONE_MOVABLE during system start, so that it was possible to have ZONE_MOVABLE interleave with ZONE_DMA or ZONE_NORMAL. This patch fixes that by checking for zone overlap before adding memory. Signed-off-by: Gerald Schaefer Reviewed-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- Reading git-diff-tree failed