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author | Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> | 2016-01-16 03:54:03 +0300 |
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committer | Luis Henriques <luis.henriques@canonical.com> | 2016-02-02 22:09:48 +0300 |
commit | bd22318fda33f995c0b2ad1df7abc96592bf35a0 (patch) | |
tree | 0eea420765a1e4dd74e8b9bda31477f3c0acb41e /mm | |
parent | 75b7953656c6e1599996f702c2fccff55d0a5fb1 (diff) | |
download | linux-bd22318fda33f995c0b2ad1df7abc96592bf35a0.tar.xz |
mm: soft-offline: check return value in second __get_any_page() call
commit d96b339f453997f2f08c52da3f41423be48c978f upstream.
I saw the following BUG_ON triggered in a testcase where a process calls
madvise(MADV_SOFT_OFFLINE) on thps, along with a background process that
calls migratepages command repeatedly (doing ping-pong among different
NUMA nodes) for the first process:
Soft offlining page 0x60000 at 0x700000600000
__get_any_page: 0x60000 free buddy page
page:ffffea0001800000 count:0 mapcount:-127 mapping: (null) index:0x1
flags: 0x1fffc0000000000()
page dumped because: VM_BUG_ON_PAGE(atomic_read(&page->_count) == 0)
------------[ cut here ]------------
kernel BUG at /src/linux-dev/include/linux/mm.h:342!
invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
Modules linked in: cfg80211 rfkill crc32c_intel serio_raw virtio_balloon i2c_piix4 virtio_blk virtio_net ata_generic pata_acpi
CPU: 3 PID: 3035 Comm: test_alloc_gene Tainted: G O 4.4.0-rc8-v4.4-rc8-160107-1501-00000-rc8+ #74
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
task: ffff88007c63d5c0 ti: ffff88007c210000 task.ti: ffff88007c210000
RIP: 0010:[<ffffffff8118998c>] [<ffffffff8118998c>] put_page+0x5c/0x60
RSP: 0018:ffff88007c213e00 EFLAGS: 00010246
Call Trace:
put_hwpoison_page+0x4e/0x80
soft_offline_page+0x501/0x520
SyS_madvise+0x6bc/0x6f0
entry_SYSCALL_64_fastpath+0x12/0x6a
Code: 8b fc ff ff 5b 5d c3 48 89 df e8 b0 fa ff ff 48 89 df 31 f6 e8 c6 7d ff ff 5b 5d c3 48 c7 c6 08 54 a2 81 48 89 df e8 a4 c5 01 00 <0f> 0b 66 90 66 66 66 66 90 55 48 89 e5 41 55 41 54 53 48 8b 47
RIP [<ffffffff8118998c>] put_page+0x5c/0x60
RSP <ffff88007c213e00>
The root cause resides in get_any_page() which retries to get a refcount
of the page to be soft-offlined. This function calls
put_hwpoison_page(), expecting that the target page is putback to LRU
list. But it can be also freed to buddy. So the second check need to
care about such case.
Fixes: af8fae7c0886 ("mm/memory-failure.c: clean up soft_offline_page()")
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/memory-failure.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 3fd99140bd6c..7e23d04393b7 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1513,7 +1513,7 @@ static int get_any_page(struct page *page, unsigned long pfn, int flags) * Did it turn free? */ ret = __get_any_page(page, pfn, 0); - if (!PageLRU(page)) { + if (ret == 1 && !PageLRU(page)) { /* Drop page reference which is from __get_any_page() */ put_page(page); pr_info("soft_offline: %#lx: unknown non LRU page type %lx\n", |