From mboxrd@z Thu Jan 1 00:00:00 1970 From: yad.naveen@gmail.com (naveen yadav) Date: Wed, 13 Apr 2011 17:08:34 +0530 Subject: [ARM] Issue of memory compaction on kernel 2.6.35.9 In-Reply-To: References: Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Dear all, we want to varify compaction on ARM and we are ?using 2.6.25.9 kernel on cortex a9. Since ARM does not have HUGETLB_PAGE support and compaction is HUGE PAGE independent so I removed from config file ****************************************************************************************************************************** # support for memory compaction config COMPACTION ? ? ? ?bool "Allow for memory compaction" ? ? ? ?select MIGRATION ? ? ? ?#depends on EXPERIMENTAL && HUGETLB_PAGE && MMU ? ? ? ?depends on EXPERIMENTAL && MMU ? help ? ? ? ? ?Allows the compaction of memory for the allocation of huge pages. ****************************************************************************************************************************** after triggering Memory Compaction by writing any value to /proc/sys/vm/compact_memory?i am getting the SVC?mode crash ****************************************************************************************************************************** #echo 1 > /proc/sys/vm/compact_memory Unable to handle kernel paging request at virtual address ee420be4 pgd = d9c6c000 [ee420be4] *pgd=00000000 Internal error: Oops: 805 [#1] PREEMPT last sysfs file: Modules linked in: CPU: 0??? Not tainted? (2.6.35.9 #16) PC is at compact_zone+0x178/0x610 LR is at compact_zone+0x138/0x610 pc : []??? lr : []??? psr: 40000093 sp : d9d75e40? ip : c0380978? fp : d9d75e94 r10: d9d74000? r9 : c03806c8? r8 : 00069704 r7 : 00069800? r6 : 00d2e080? r5 : c04ea080? r4 : d9d75e9c r3 : 60000093? r2 : 00000002? r1 : ee420be4? r0 : ee430b82 Flags: nZcv? IRQs off? FIQs on? Mode SVC_32? ISA ARM? Segment us ****************************************************************************************************************************** We ?tried to narrow down the prob... I found crash is form ?del_page_from_lru_list(zone, page, page_lru(page)); ? function isolate_migratepages { ----------- /* Successfully isolated */ ? ? ? ? ? ? ? ?del_page_from_lru_list(zone, page, page_lru(page)); ? ? ? ?-------------------------------------------------- } In my ARM board have only one zone (Node 0, zone???Normal) ****************************************************************************************************************************** VDLinux#> cat /proc/buddyinfo Node 0, zone ? Normal ? ? ?5 ? ? ?4 ? ? ?4 ? ? ?2 ? ? ?1 ? ? ?3 ? ? ?0 ? ? 2 ??????3??????4??????2??????1??????7 ****************************************************************************************************************************** Can some one guide why I am geeting the crash and how to debugg this problem Thanks