The patch titled
memcg: fix prepare migration
has been added to the -mm tree. Its filename is
memcg-fix-prepare-migration.patch
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------------------------------------------------------
Subject: memcg: fix prepare migration
From: Andrea Arcangeli <aarcange@xxxxxxxxxx>
If a signal is pending (task being killed by sigkill)
__mem_cgroup_try_charge will write NULL into &mem, and css_put will oops
on null pointer dereference.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: [<ffffffff810fc6cc>] mem_cgroup_prepare_migration+0x7c/0xc0
PGD a5d89067 PUD a5d8a067 PMD 0
Oops: 0000 [#1] SMP
last sysfs file: /sys/devices/platform/microcode/firmware/microcode/loading
CPU 0
Modules linked in: nfs lockd nfs_acl auth_rpcgss sunrpc acpi_cpufreq pcspkr sg [last unloaded: microcode]
Pid: 5299, comm: largepages Tainted: G W 2.6.34-rc3 #3 Penryn1600SLI-110dB/To Be Filled By O.E.M.
RIP: 0010:[<ffffffff810fc6cc>] [<ffffffff810fc6cc>] mem_cgroup_prepare_migration+0x7c/0xc0
Signed-off-by: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Daisuke Nishimura <nishimura@xxxxxxxxxxxxxxxxx>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: Balbir Singh <balbir@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memcontrol.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff -puN mm/memcontrol.c~memcg-fix-prepare-migration mm/memcontrol.c
--- a/mm/memcontrol.c~memcg-fix-prepare-migration
+++ a/mm/memcontrol.c
@@ -2429,8 +2429,9 @@ int mem_cgroup_prepare_migration(struct
}
unlock_page_cgroup(pc);
+ *ptr = mem;
if (mem) {
- ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false);
+ ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, ptr, false);
css_put(&mem->css);
}
*ptr = mem;
_
Patches currently in -mm which might be from aarcange@xxxxxxxxxx are
origin.patch
memcg-fix-prepare-migration.patch
define-madv_hugepage.patch
mincore-cleanups.patch
mincore-break-do_mincore-into-logical-pieces.patch
mincore-pass-ranges-as-startend-address-pairs.patch
mincore-do-nested-page-table-walks.patch
mm-migration-take-a-reference-to-the-anon_vma-before-migrating.patch
mm-migration-do-not-try-to-migrate-unmapped-anonymous-pages.patch
mm-share-the-anon_vma-ref-counts-between-ksm-and-page-migration.patch
mm-allow-config_migration-to-be-set-without-config_numa-or-memory-hot-remove.patch
mm-allow-config_migration-to-be-set-without-config_numa-or-memory-hot-remove-fix.patch
mm-export-unusable-free-space-index-via-proc-unusable_index.patch
mm-export-fragmentation-index-via-proc-extfrag_index.patch
mm-move-definition-for-lru-isolation-modes-to-a-header.patch
mm-compaction-memory-compaction-core.patch
mm-compaction-memory-compaction-core-fix.patch
mm-compaction-memory-compaction-core-fix-page-buddy-can-go-away-before-reading-page_order-while-isolating-pages-for-migration.patch
mm-compaction-add-proc-trigger-for-memory-compaction.patch
mm-compaction-add-proc-trigger-for-memory-compaction-fix.patch
mm-compaction-add-proc-trigger-for-memory-compaction-fix-fix.patch
mm-compaction-add-sys-trigger-for-per-node-memory-compaction.patch
mm-compaction-direct-compact-when-a-high-order-allocation-fails.patch
mm-compaction-direct-compact-when-a-high-order-allocation-fails-reject-fix.patch
mm-compaction-add-a-tunable-that-decides-when-memory-should-be-compacted-and-when-it-should-be-reclaimed.patch
mm-migration-allow-the-migration-of-pageswapcache-pages.patch
mm-migration-allow-the-migration-of-pageswapcache-pages-fix.patch
mm-compaction-do-not-display-compaction-related-stats-when-config_compaction.patch
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