| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20090206171724.77c4b5ed.kamezawa.hiroyu@jp.fujitsu.com>
Date: Fri, 6 Feb 2009 17:17:24 +0900
From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
To: linux-kernel@...r.kernel.org
Cc: akpm@...ux-foundation.org, mm-commits@...r.kernel.org,
davem@...emlloft.net, heiko.carstens@...ibm.com, mel@....ul.ie,
stable@...nel.org
Subject: Re: +
mm-fix-memmap-init-to-initialize-valid-memmap-for-memory-hole.patch added
to -mm tree
On Thu, 05 Feb 2009 09:29:54 -0800
akpm@...ux-foundation.org wrote:
>
> The patch titled
> mm: fix memmap init to initialize valid memmap for memory hole
> has been added to the -mm tree. Its filename is
> mm-fix-memmap-init-to-initialize-valid-memmap-for-memory-hole.patch
>
> Before you just go and hit "reply", please:
> a) Consider who else should be cc'ed
> b) Prefer to cc a suitable mailing list as well
> c) Ideally: find the original patch on the mailing list and do a
> reply-to-all to that, adding suitable additional cc's
>
> *** Remember to use Documentation/SubmitChecklist when testing your code ***
>
> See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
> out what to do about this
>
> The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
>
Sorry, Kosaki reported me that this patch breaks ia64 compile/boot.
So, I'm fixing the bug in cooperation with him, now.
I think I can send a fix soon. But I hope this patch set for BOOT will be
tested under various arch/configs before going up to.
Thanks,
-Kame
> ------------------------------------------------------
> Subject: mm: fix memmap init to initialize valid memmap for memory hole
> From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
>
> If PFN is not in early_node_map[] then struct page for it is not
> initialized. If there are holes within a MAX_ORDER_NE_PAGES range of
> pages, then PG_reserved will not be set. Code that walks PFNs within
> MAX_ORDER_NR_PAGES will the use uninitialized struct pages.
>
> To avoid any problems, this patch initializes holes within a
> MAX_ORDER_NR_PAGES that valid memmap exists but is otherwise unused.
>
> Sayeth davem:
>
> What's happening is that the assertion in mm/page_alloc.c:move_freepages()
> is triggering:
>
> BUG_ON(page_zone(start_page) != page_zone(end_page));
>
> Once I knew this is what was happening, I added some annotations:
>
> if (unlikely(page_zone(start_page) != page_zone(end_page))) {
> printk(KERN_ERR "move_freepages: Bogus zones: "
> "start_page[%p] end_page[%p] zone[%p]\n",
> start_page, end_page, zone);
> printk(KERN_ERR "move_freepages: "
> "start_zone[%p] end_zone[%p]\n",
> page_zone(start_page), page_zone(end_page));
> printk(KERN_ERR "move_freepages: "
> "start_pfn[0x%lx] end_pfn[0x%lx]\n",
> page_to_pfn(start_page), page_to_pfn(end_page));
> printk(KERN_ERR "move_freepages: "
> "start_nid[%d] end_nid[%d]\n",
> page_to_nid(start_page), page_to_nid(end_page));
> ...
>
> And here's what I got:
>
> move_freepages: Bogus zones: start_page[2207d0000] end_page[2207dffc0] zone[fffff8103effcb00]
> move_freepages: start_zone[fffff8103effcb00] end_zone[fffff8003fffeb00]
> move_freepages: start_pfn[0x81f600] end_pfn[0x81f7ff]
> move_freepages: start_nid[1] end_nid[0]
>
> My memory layout on this box is:
>
> [ 0.000000] Zone PFN ranges:
> [ 0.000000] Normal 0x00000000 -> 0x0081ff5d
> [ 0.000000] Movable zone start PFN for each node
> [ 0.000000] early_node_map[8] active PFN ranges
> [ 0.000000] 0: 0x00000000 -> 0x00020000
> [ 0.000000] 1: 0x00800000 -> 0x0081f7ff
> [ 0.000000] 1: 0x0081f800 -> 0x0081fe50
> [ 0.000000] 1: 0x0081fed1 -> 0x0081fed8
> [ 0.000000] 1: 0x0081feda -> 0x0081fedb
> [ 0.000000] 1: 0x0081fedd -> 0x0081fee5
> [ 0.000000] 1: 0x0081fee7 -> 0x0081ff51
> [ 0.000000] 1: 0x0081ff59 -> 0x0081ff5d
>
> So it's a block move in that 0x81f600-->0x81f7ff region which triggers
> the problem.
>
> So I did a lot (and I do mean _A LOT_) of digging. And it seems that
> unless you set HOLES_IN_ZONE you have to make sure that all of the
> memmap regions of free space in a zone begin and end on an HPAGE_SIZE
> boundary (the requirement used to be that it had to be MAX_ORDER
> sized).
>
> Well, this assumption enterred the tree back in 2005 (!!!) from
> the following commit in the history-2.6 tree:
>
> commit 69fba2dd0335abec0b0de9ac53d5bbb67c31fc60
> Author: Kamezawa Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
> Date: Fri Jan 7 22:01:35 2005 -0800
>
> [PATCH] no buddy bitmap patch revisit: for mm/page_alloc.c
>
>
> Reported-by: David Miller <davem@...emlloft.net>
> Acked-by: Mel Gorman <mel@....ul.ie>
> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
> Cc: Heiko Carstens <heiko.carstens@...ibm.com>
> Cc: <stable@...nel.org>
> Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
> ---
>
> include/linux/mmzone.h | 6 ------
> mm/page_alloc.c | 13 +++++++++++--
> 2 files changed, 11 insertions(+), 8 deletions(-)
>
> diff -puN include/linux/mmzone.h~mm-fix-memmap-init-to-initialize-valid-memmap-for-memory-hole include/linux/mmzone.h
> --- a/include/linux/mmzone.h~mm-fix-memmap-init-to-initialize-valid-memmap-for-memory-hole
> +++ a/include/linux/mmzone.h
> @@ -1070,12 +1070,6 @@ void sparse_init(void);
> #define sparse_index_init(_sec, _nid) do {} while (0)
> #endif /* CONFIG_SPARSEMEM */
>
> -#ifdef CONFIG_NODES_SPAN_OTHER_NODES
> -#define early_pfn_in_nid(pfn, nid) (early_pfn_to_nid(pfn) == (nid))
> -#else
> -#define early_pfn_in_nid(pfn, nid) (1)
> -#endif
> -
> #ifndef early_pfn_valid
> #define early_pfn_valid(pfn) (1)
> #endif
> diff -puN mm/page_alloc.c~mm-fix-memmap-init-to-initialize-valid-memmap-for-memory-hole mm/page_alloc.c
> --- a/mm/page_alloc.c~mm-fix-memmap-init-to-initialize-valid-memmap-for-memory-hole
> +++ a/mm/page_alloc.c
> @@ -2633,9 +2633,18 @@ void __meminit memmap_init_zone(unsigned
> * exist on hotplugged memory.
> */
> if (context == MEMMAP_EARLY) {
> + int nid_from_node_memory_map;
> +
> if (!early_pfn_valid(pfn))
> continue;
> - if (!early_pfn_in_nid(pfn, nid))
> + /*
> + * early_pfn_to_nid() returns -1 if the page doesn't
> + * exist in early_node_map[]. Initialize it in force
> + * and set PG_reserved at el.
> + */
> + nid_from_node_memory_map = early_pfn_to_nid(pfn);
> + if (nid_from_node_memory_map > -1 &&
> + nid_from_node_memory_map != nid)
> continue;
> }
> page = pfn_to_page(pfn);
> @@ -3002,7 +3011,7 @@ int __meminit early_pfn_to_nid(unsigned
> return early_node_map[i].nid;
> }
>
> - return 0;
> + return -1;
> }
> #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
>
> _
>
> Patches currently in -mm which might be from kamezawa.hiroyu@...fujitsu.com are
>
> origin.patch
> linux-next.patch
> mm-fix-memmap-init-to-initialize-valid-memmap-for-memory-hole.patch
> proc-pid-maps-dont-show-pgoff-of-pure-anon-vmas.patch
> proc-pid-maps-dont-show-pgoff-of-pure-anon-vmas-checkpatch-fixes.patch
> cgroup-css-id-support.patch
> cgroup-fix-frequent-ebusy-at-rmdir.patch
> memcg-use-css-id.patch
> memcg-hierarchical-stat.patch
> memcg-fix-shrinking-memory-to-return-ebusy-by-fixing-retry-algorithm.patch
> memcg-fix-oom-killer-under-memcg.patch
> memcg-fix-oom-killer-under-memcg-fix2.patch
> memcg-fix-oom-killer-under-memcg-fix.patch
> memcg-show-memcg-information-during-oom.patch
> memcg-show-memcg-information-during-oom-fix2.patch
> memcg-show-memcg-information-during-oom-fix.patch
>
> --
> To unsubscribe from this list: send the line "unsubscribe mm-commits" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists